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GI Jonas
02-13-2012, 08:30 PM
Hello all,I wanted to present a new creation of mine that I came up with out of frustration over a slightly less than stellar item on our cars.I have 2 e24's in my life that I care for including my own and both have needed new diff mounts.This seems reasonable on an 80's vehicle however in looking at the part it is clear to me that this must be a common issue and from what I have read online it is.So to the point, I have designed a beefy replacement diff mount that is not only far stronger but has replaceable urethane bushings so the unit itself is essentially rebuild-able.

I am not a stranger to fabricating and marketing parts but I have not done so in some time,however I decided to get something going again and I think this is where I will start.The pics and specs are listed below.

This unit pictured is a prototype and is the unit that will stay on my car.With enough interest I will be Building jigs and getting prepped to make a run of these.I have learned in the past not to jump into offering an item to market without first testing and getting some feedback.My problem here is that I don't currently have access to a running car to do so myself so I want to present an offer to fellow forum goers to help me out.

This is what I would LIKE to do.If anyone one is interested I would be willing to ship 5 of these units out to willing guineas at 75% cost compared to what I feel I need to get when producing these.The only requirement is that the person to request must have a running e24/e28 that they can install the mount into ASAP and and put some miles on it.I am fully confident in the unit but I wont go ahead until I have some legitimate opinion based on road testing.

Upon approval from buyers and after any needed changes are made, I will go ahead and offer a group buy to the forum and possibly other forums as well.From what I have figured I think I am going to shoot for something in the $175-$195 per unit range.It wont be worth my time at any less than that and I think considering you wont have to buy another it int bad compared to $80ish for an OEM piece.Also the bushings are readily available at local parts stores and are inexpensive,not to mention you probably wont need to replace them anyways.

Anyone interested should understand that there is obviously going to be less deflection in the diff due to the added rigidity,this is not a "solid" mount by any means but this item may be more suited to those concerned about putting down additional torque and not so much those obsessed with the smoothest possible ride.However until testing I don't know just how it will feel and it very well may be that there is nothing but a positive difference...we will see.


Rough specs:

Back plate reinforcement - 1/8 "

Brackets and bushing bores - 3/16's "

Diff mounting tab - 1/2"

Bushing through-pin - 7/8' solid bar

Weight - not sure yet, roughly only about double the stocker surprisingly...weight weenies beware :D

All parts are TIG welded,plasma cut and will be acid dipped and painted one of possibly a half dozen colors or so.I also will include hardware which is needed to clear the bushing.If anyone wants un-coated I can do that as well,at this point I most likely will not get into powder-coating them.



http://i120.photobucket.com/albums/o199/znut_2007/IMG_2836.jpg


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2837.jpg


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2843.jpg


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2842.jpg




This is essentially what would arrive at your door :D


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2847.jpg


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2848.jpg


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2849.jpg


http://i120.photobucket.com/albums/o199/znut_2007/IMG_2855.jpg






http://i120.photobucket.com/albums/o199/znut_2007/IMG_2857.jpg



http://i120.photobucket.com/albums/o199/znut_2007/IMG_2858.jpg




So,as I stated if anyone is interested and follows the criteria I would like to treat this as a first come first serve in terms of those to receive test units.If I get 5 people to agree I will collect needed materials,get them fabbed up and will not request payment until I am ready to ship (give or take 1 week).Also keep in mind that I stand behind everything i make 100%."If I make it and you break it,then back I will take it" :D .Please contact VIA PM if you would like in on the deal,and anyone who would like to comment on future interest please do so.I really need to get an idea of how many would be interested in this,thanks.

ShapeShifter
02-13-2012, 09:06 PM
Looks nice. Does it transmit any vibrations?

Also, the next weakest link is the structure it's bolted to. They have been know to crack in that area.

I'm pretty sure I would be in for one.

bimas
02-13-2012, 09:52 PM
Very nicely done. I'd like to see one in a finished paint.

Coupenut
02-13-2012, 10:22 PM
Looks nice! You might want to post on the E23 and 28 boards for additional interest

Flash635
02-13-2012, 10:44 PM
Also, the next weakest link is the structure it's bolted to. They have been know to crack in that area.
.

IMO it would probably be ok because the diff can rotate on the bush rather than transmit force to the place it's mounted on.
I don't think the diff would transmit a lateral rotational force, or much anyway.

GI Jonas
02-13-2012, 11:13 PM
IMO it would probably be ok because the diff can rotate on the bush rather than transmit force to the place it's mounted on.
I don't think the diff would transmit a lateral rotational force, or much anyway.


Agreed.

Flash635
02-14-2012, 12:07 AM
I was getting car wood looking at the pics.

I am a little dismayed with how much strengthening these cars need in particular places when you consider how much they cost when new.
A lot of the parts are only just strong enough to hold on with very little safety margin.

Slammed740
02-15-2012, 12:12 PM
What kinda price are we estimating here? I may be interested in on for my e28.

Looks like a very nice piece, I would take one raw and paint it myself I think.

demetk
02-15-2012, 01:56 PM
I would be interested. Let me know your price. Pink might be nice.

GI Jonas
02-15-2012, 03:29 PM
Price is in the post folks :D.I posted a link at e28 forums and have about enough people on board for a test run of these.Anyone serious should send me a PM.I am only counting those who are sure they want to be a tester and those who can get on it soon.Im going with $135 shipped on test units.

thanks

eric1ono
02-15-2012, 04:52 PM
nice looking assembly, and it looks very well thought out. I do have one question, potentially it looks like the diff could move side to side under heavy corning. I could be missing something, but I am assuming the output shafts will have some flex in them and won't keep the diff fixed.

Again, not complaining, I like the concept. Just making sure all possibilities are covered.

Thanks,

Eric

ShapeShifter
02-15-2012, 04:58 PM
What's your fab time/ shipping schedule looking like?

brannman
02-15-2012, 06:06 PM
I will comitt to one of these for my race car, even if I dont use it immediately. I fabbed up this over a year ago but it hasnt been track tested yet...

http://www.s14.net/photopost/data/500/solid_diif_mount_01.jpg

http://bigcoupe.com/phpBB2/viewtopic.php?t=8858&highlight=

mooseheadm5
02-15-2012, 09:52 PM
I'm going to post what I posted over on MyE28:

That looks rock solid for sure. I have a question or two, though. What is the plate for? Do you weld it to the body for structural reinforcement? Do you think maybe you have made it overly bomb proof? Not saying it should be made weaker, just that it may be possible to reduce welding time, material costs, and cost to the customer if you made it less massive.

Good luck. I love to see stuff like this out there.
_________________

It is a good design and would definitely be bombproof. Looking at it more closely, I would add something to prevent the back of the diff moving side to side. If you make the center a tube rather than a bar and run a long bolt through it, you can put fender washers on either end to prevent lateral movement. It would add very little cost and no additional fabrication time.

If you want additional pointers, send me an email through the board and we can talk about optimizing the design for effectiveness, cost, and ease of production. I'd also be interested in carrying them on my website.

GI Jonas
02-15-2012, 10:27 PM
I want to post a link over to the e28 board.However I will try to stay in the conversation in both threads. http://www.mye28.com/viewtopic.php?t=101969.

Here is just a copy paste of my response over there.

Thanks for the attention guys,I'll try to respond in some order here.First off is the confusion about the backing plate.In all honesty I am not entirely sold on that particular parts necessity myself,however I though it was a good additional measure as far as spreading the load.The mounting area on the car is a bit thin,but it is possible that it can be omitted without issue,but I have yet to regret piece of mind from overbuilding something.And to answer the mounting question,moosehead is right as far as it being basically a spacer that the mounting bolts pass through...no welding.

Quote: On bf someone asked about lateral movement, should that be a concern?

If you look at the mount you will be able to picture that no movement of the diff is eliminated in any plane or direction, but rather DECREASED in all directions.Is this an issue? well this is why I need some folks to test the unit.I am not offering a handful of miracles here just hoping to make an improvement on a weakness that i see.I do not have a lab laden with calibrated test equipment and wouldn't use it if I did.I know that at the end of the day real world testing and street miles are the ONLY thing that really counts.Many questions will be answered after it gets some time on a few cars.

Quote: I would add something to prevent the back of the diff moving side to side. If you make the center a tube rather than a bar and run a long bolt through it, you can put fender washers on either end to prevent lateral movement. It would add very little cost and no additional fabrication time.

I considered this as well.However with the diff being solidly mounted to the sub frame I think any side to side "walking" of the rear of the diff would signify that you have bigger issues.I also didn't want to compromise any of the integrity of the pin,though Im sure a good chromoly tube would do the trick.I think though if i did go that route I would just drill and thread the ends of the rod on the lathe.

It looks at this point like I have a half dozen folks or so who have contacted me with the interest in taking a test unit.I am going to be sending a PM to all interested here and at BF to solidify their intentions.Once done I hope to have these units ready to go by late next week,then we can see whats really going to happen.Either it will not be worth the time and energy or Im going to get some good input that will inspire me to get the ball rolling.Once the test units are out there it will be up to the testers to answer all your questions, without any bias. http://www.mye28.com/images/smiles/icon_biggrin.gif

Thanks,Jonas

mooseheadm5
02-15-2012, 10:57 PM
Remember that the rear diff mount also resists the forces trying to twist the subframe about the Z axis of the car as well lateral lateral loading due to cornering. Allowing it to float laterally takes away some of this resistance, which is generally a bad thing. The forces on this would not cause issues with a tube vs. a solid bar. If you plan to make these as a production piece, you have to think about totaling up your time and tooling requirements. Why bother boring holes, and doing a bottoming tap, two operations that require time and tooling wear, when you can just cut a tube to length?

http://www.onlinemetals.com/merchant.cfm.....p;id=250&top_cat=0 (http://www.onlinemetals.com/merchant.cfm?pid=7679&step=4&showunits=inches&id=250&top_cat=0)

In addition, I would use a U channel for the mount tab instead of flat bar with those formed straps. Cut a 7/8" channel across it with a ball mill and mate the tube to the U channel with 2 or 3 welds. I'd also be tempted to use a weld nut rather than tapping that hole. Remember, the tab it is bolted to is cast aluminum. It doesn't need to be super thick, and neither does the tube (though I know it is 7/8" to gain bushing size.)

You also spend a lot of time welding those bushing tubes all the way around on both sides. Considering the direction and magnitude of the forces on those parts, this is unnecessary time, filler, and welding gas spent and potential extra heat to warp the part.

Anyway, those are my $0.02. Take them or leave them.

GI Jonas
02-15-2012, 11:06 PM
All good points.And you are certainly right about cornering loads.Consider a pin retainer done on the test units!As far as the production is concerned I already have many ideas on improving the design for building multiple units.What is pictured is just a prototype,it works but yes the end product will be of better quality and more efficiently put together.The one you see was made from my box of scrap http://www.mye28.com/images/smiles/laugh2.gif

Good stuff guys,keep it coming.

mooseheadm5
02-15-2012, 11:19 PM
You definitely don't have any quality issues there, just time sink issues that might reduce the financial viability of the project. Nothing like having to give up because it costs too much to make.

BTW, here is the U channel I'd use- McMaster Carr P/N 7779T12, assuming it is wide enough for the task, though you can probably find a wider one with the same 1/2" flanges at a metal supplier.

I was thinking that you wouldn't need that base plate if you changed the design a little, but I like the idea that you could weld it in place to reduce the chance of cracking that Porsche Dude was talking about.

I had been thinking about making something like this using BMW mount bushings from an E34, but this thing looks like it'll work just fine (and saves me the trouble of developing it.) Those poly inserts are probably cheaper and just as effective at noise isolation. Now if the initial units prove to be too noisy, I can see ways to make that change with your basic design.

DCpower
02-16-2012, 03:22 AM
I am also interested - 1 or 2 units...

Flash635
02-16-2012, 08:54 AM
Does the diff need lateral control seeing as it's bolted to the subframe?

If so, the bar could be a bit longer and circlips fitted to retain the bush and prevent lateral movement.
Squeaking might be a problem, I know it's common to fit PU bushes with moly grease but I find that it can dry and gall the bushes. Teflon grease would be better or dry graphite.
You can also get PU bushes impregnated with moly or you could use phosphor bronze.
Another alternative is to drill the bar and fit zerk grease nipples.

I think I'd use teflon grease.

GI Jonas
02-16-2012, 11:28 AM
Does the diff need lateral control seeing as it's bolted to the subframe?

If so, the bar could be a bit longer and circlips fitted to retain the bush and prevent lateral movement.
Squeaking might be a problem, I know it's common to fit PU bushes with moly grease but I find that it can dry and gall the bushes. Teflon grease would be better or dry graphite.
You can also get PU bushes impregnated with moly or you could use phosphor bronze.
Another alternative is to drill the bar and fit zerk grease nipples.

I think I'd use teflon grease.

I think the lateral movement is enough of a potential issue to justify an easy bit of insurance on it,It shouldn't move MUCH,but a little is enough to cause undue fatigue and likely performance problems.

As far as the squeak,I doubt it. the pin isn't going to be pivoting on those bushings like a control arm.Any pivoting will be slight enough I do not see them making noise,of course lube is good anyways and the fit is tight enough it needs it anyway for installation.I am really hoping these bushings work well as they are readily available and are a good durometer.What exactly I don't know but they are notably more supple than typical aftermarket poly bushings,sometimes more akin to black stones.

Jzad
02-16-2012, 04:04 PM
That looks great. If I hadnt just replace mine I would totally try one of those nice job looks like you could run doughnuts all day and not worry about losing your rear end

carsnplanes
02-16-2012, 04:58 PM
Great design and rework!
What I'd be worried about is not so much the re-design of the mount but BMW's use of one hold down attach bolt. That's pretty lame if you ask me. You could design all the strength into the mount itself but the one bolt that attaches the case to the the mount will find some way of coming loose. In fact even more so now with your strengthened design as it will be less forgiving to the attach bolts and hardware. It was mentioned by another poster that a welded nut to the plate would be better than a tapped thread on a thin plate as you have it now. In any case the more rigid the mount, the more stress on the attach hardware. The original rubber mount "gave" a lot which put less stress on the attaching hardware.

GI Jonas
02-16-2012, 07:06 PM
Guys I did a quick rework and made up sketch.Im thinking of using the idea of channel in 3" width mounted to the pin and also flipping the bushings as suggested.The channel would act as the lateral stop against the bushing flange as well as being the diff mount.This also allows for using the stock hardware which was impossible before.Also considering flipping the channel opposite of whats shown so that it actually saddles the "horn" of the diff cover preventing it from deflecting and making contact with the brackets.Let me know what you think.


http://i120.photobucket.com/albums/o199/znut_2007/Untitled-2.jpg


http://i120.photobucket.com/albums/o199/znut_2007/newmount.jpg




Great design and rework!
What I'd be worried about is not so much the re-design of the mount but BMW's use of one hold down attach bolt. That's pretty lame if you ask me. You could design all the strength into the mount itself but the one bolt that attaches the case to the the mount will find some way of coming loose. In fact even more so now with your strengthened design as it will be less forgiving to the attach bolts and hardware. It was mentioned by another poster that a welded nut to the plate would be better than a tapped thread on a thin plate as you have it now. In any case the more rigid the mount, the more stress on the attach hardware. The original rubber mount "gave" a lot which put less stress on the attaching hardware.Unfortunately you are right.However there is only so much I can do here!:eyecrazy

Every time you strengthen one thing you open a can of worms for breakage elsewhere,just look what happens when you boost a motor:(

FernandoBunster
02-16-2012, 07:44 PM
Guys I did a quick rework and made up sketch.Im thinking of using the idea of channel in 3" width mounted to the pin and also flipping the bushings as suggested.The channel would act as the lateral stop against the bushing flange as well as being the diff mount.This also allows for using the stock hardware which was impossible before.Also considering flipping the channel opposite of whats shown so that it actually saddles the "horn" of the diff cover preventing it from deflecting and making contact with the brackets.Let me know what you think.

http://i120.photobucket.com/albums/o199/znut_2007/Untitled-2.jpg


http://i120.photobucket.com/albums/o199/znut_2007/newmount.jpg



Unfortunately you are right.However there is only so much I can do here!:eyecrazy

Every time you strengthen one thing you open a can of worms for breakage elsewhere,just look what happens when you boost a motor:(

Great design and manufacturing but I'm not sure that this is not overkill. My OEM diff mounts seem to l last many hundreds of thousand miles and are relatively cheap and easy to replace.

samsonevickis
02-16-2012, 09:15 PM
Great design and manufacturing but I'm not sure that this is not overkill. My OEM diff mounts seem to l last many hundreds of thousand miles and are relatively cheap and easy to replace.

I believe he is intending this for folks with better than stock power and I assume "boost"

I am very interested in this design and implementation, but I don't have a use for it myself as my OEM mount was replaced at some point and has no issues after all these years.

Keep up the good work GI!

Freshbread
02-16-2012, 09:39 PM
Mount looks awesome and certainly look forward to some R&D on it and a final. Do I need it negative...but choices in our limited product offerings outside of OEM is near zero.

av8r4aa
02-16-2012, 10:55 PM
Looks like the dangerous roads of Afganistan could not hurt it !!!!

GI Jonas
02-16-2012, 11:47 PM
Great design and manufacturing but I'm not sure that this is not overkill. My OEM diff mounts seem to l last many hundreds of thousand miles and are relatively cheap and easy to replace.



I believe he is intending this for folks with better than stock power and I assume "boost"


Exactly.Nothing is for everyone.Unless by chance it turns out that everyone sees some notable instant advantage in testing,even then....

I did this for myself and am simply offering it to those who want it enough to buy one.In all honesty this will most likely be a limited run even if it is popular,we will see.At the moment between two forums i have been assaulted with requests to buy a test unit overnight so clearly there is some desire out there,whether people "need" it or just want one:D

dm635
02-17-2012, 07:09 AM
I think it's great trying to improve a weak link. I filled my mount with "Window Weld" all the way to the top. Can lift by the diff & it doesn't give or flex.

GI Jonas
02-23-2012, 11:20 PM
Just letting everyone know that everything is on schedule at this point.Got all the units done,just waiting on the bushings.Ill post pics and details tomorrow!

GI Jonas
03-01-2012, 10:18 PM
Well after a bit of a fiasco with the bushing supplier I have finally received them and have 8 units done and ready to go out on Monday.All who requested a test unit will get a PM soon and I still have a couple left for any additional people who want one.

Here are the pics of the revised design.The only promise I did not come through on is making able to accept the stock fasteners,no biggie,they will come with new ones.As you can see, lateral movement is a thing of the past.


http://i120.photobucket.com/albums/o199/znut_2007/gh001.jpg

http://i120.photobucket.com/albums/o199/znut_2007/gh004.jpg


http://i120.photobucket.com/albums/o199/znut_2007/gh002.jpg


http://i120.photobucket.com/albums/o199/znut_2007/gh009.jpg



http://i120.photobucket.com/albums/o199/znut_2007/gh008.jpg



http://i120.photobucket.com/albums/o199/znut_2007/gh010.jpg[/img]

Also here are the specs on the bushing that i ended up settling on.There are likely others in this size that people can source if they want to experiment.# 9.9482.They are $14 for a set of 4.


http://energysuspension.com/universal-pr.....-mounts-isolators.html (http://energysuspension.com/universal-products/link-flange-type-bushings-universal-mounts-isolators.html)

DCpower
03-04-2012, 02:03 PM
that looks very good

AdamBath
03-04-2012, 02:26 PM
Can't wait to get this in, hopefully it gets here before I go on my trip Friday. I just got my car back to 100% today so this will be great to try out.

toki66
03-04-2012, 02:32 PM
I want to buy this... Please let me know if you sell it.

oldymcoldington
03-04-2012, 04:12 PM
in my laundry list of projects is an LSD, would be a good idea to source this as part of the project, let me know if/when production starts, and if you have any additional units left over thanks!

AdamBath
03-04-2012, 04:19 PM
The good thing about this part is it'll also work for 5 and 7 series...

brannman
03-06-2012, 02:14 PM
Let me know when I can get in line for one. It would be a test/spare for the car, wouldn't be able to use it immediately.

joecoolinatl
03-07-2012, 12:44 PM
this looks awesome!

Badgas
03-07-2012, 10:25 PM
Well, now I want one to!

AdamBath
03-08-2012, 03:01 PM
http://i613.photobucket.com/albums/tt218/Elysian893/IMG_20120308_135415.jpg

Got mine! Unfortunately it's raining quite a bit today and I'm getting ready to embark on a drive to Washington state with my family so I won't be able to install it until the 19th or so.

e24mpwr
03-08-2012, 03:39 PM
I also just replaced my diff mount last year, but I'd consider buying it if we think it is stronger and lighter than the OEM part. Any opinions?

GI Jonas
03-08-2012, 03:43 PM
Its not lighter.Ive been meaning to weigh the two on the digi but Im guessing 50
% heavier than stock.

AdamBath
03-19-2012, 01:58 PM
I'm back home now, going to try to install it this afternoon. We've got thunderstorms rolling in so hopefully I can get it done before that.

Got it installed. Pretty happy with how it feels. When giving it gas or letting off it has just the right amount of bounce that it's not harsh, it feels very much like the OEM mount but now I know it's a lot stronger (my entire drivetrain is held in by urethane so I can judge the bounce of the rear mount fairly accurately since I know it's not the drivetrain moving). If I ever get around to turboing it will be nice to have the rear end all sorted already.

Anyone want mine now that my car is dead? :(

AdamBath
03-20-2012, 11:02 AM
Anyone want mine now that my car is dead? :(

carsnplanes
03-20-2012, 12:01 PM
Anyone want mine now that my car is dead? :(


Reading this after re reading your previous thread about not being able to install it because thunderstorms rolling in. Incredible that those storms then, would be the demise of your car today. Was the rain that you had the accident in the result of that storm you spoke of? Just so spooky.
Such sad news but glad you are alright.

Shipper
03-20-2012, 11:31 PM
Well after a bit of a fiasco with the bushing supplier I have finally received them and have 8 units done and ready to go out on Monday.All who requested a test unit will get a PM soon and I still have a couple left for any additional people who want one.

Here are the pics of the revised design.The only promise I did not come through on is making able to accept the stock fasteners,no biggie,they will come with new ones.As you can see, lateral movement is a thing of the past.


http://i120.photobucket.com/albums/o199/znut_2007/gh001.jpg

http://i120.photobucket.com/albums/o199/znut_2007/gh004.jpg


http://i120.photobucket.com/albums/o199/znut_2007/gh002.jpg


http://i120.photobucket.com/albums/o199/znut_2007/gh009.jpg



http://i120.photobucket.com/albums/o199/znut_2007/gh008.jpg



http://i120.photobucket.com/albums/o199/znut_2007/gh010.jpg[/img]

Also here are the specs on the bushing that i ended up settling on.There are likely others in this size that people can source if they want to experiment.# 9.9482.They are $14 for a set of 4.


http://energysuspension.com/universal-pr.....-mounts-isolators.html (http://energysuspension.com/universal-products/link-flange-type-bushings-universal-mounts-isolators.html)

Firstly, when I first looked at this post today I was hoping it was for the sideloader diff. Alas, your fine workmanship won't fit my old girl.

Secondly. As a structural engineer working in the marine environment where constant movement always leads to fatigue failure I can not help but notice the proximity of two of the four chassis bolts to the edge of the black base/mounting plate. In Australia there is a standard that gives edge clearances to bolt holes in steel base plates. The distance from bolt hole edge to plate edge looks well under sized. I won't discuss all the nasty things that can happen if these distances are not maintained. May be something to look at if you consider a re-design in the future.

Okay, a quick google search has found what appears to be the US standard for bolt edge distances. Given we don't use inches, but millimetres, I have no idea if you comply.

http://www.structuralsteeldetailer.us/edge_distance.html

GI Jonas
03-21-2012, 11:41 PM
You have a good point and I was planning on resolving that on the next batch.It was something I didnt account for in the dimensions and has bothered me a little...though I think it maybe alright in reality...could be wrong.

Shipper
03-29-2012, 01:58 AM
Don't get me wrong. I think your effort is fantastic. If my 633 was not the old E12 chassis with the sideloader diff I'd buy one of yours myself (with the altered bolt pattern). Note that your original mock up and your drawing along with the first one the manufacturer supplied you with appeared to have sufficient bolt clearances. I think they just got a little lazy when they manufactured the second run.

This will only be an issue if bolts get loose so every 10,000 mile service should also check diff mounting bolt tensions. A loose bolt hits against the bolt hole as bolt holes are generally 1mm to 2mm larger in diamaeter than the receiving bolt. So that play can cause areas of high stress that lead to cracking, crack growth and failed diff mounts. My sideloader went that way, cracked along the bolt line due to loose bolts.

Again mighty impressed with your effort.

dcains
05-07-2015, 09:15 AM
Any updates on this?

Shipper
05-08-2015, 09:54 PM
I've swapped out my e12 rear subframe for an e28 subframe. I'm also running a 380hp+ S38B38. I'd buy this now!!! I'm thinking I need bombproof!

captpkelly
05-10-2015, 03:06 AM
This thread was from before my time on the forum... I'd love to be able to get one! Are they still available???

Thanks,
Pat

Gprieto
06-04-2016, 04:00 PM
Hi Jonas. I'm in. But I want/need one sooner than later please let me know how much and when it can be delivered. It is a track car and I need something closer to bulletproof. Also attempting a run at SEMA 2016.

E2heNnyHate
12-29-2017, 11:27 PM
Can I get one

94530inh
04-30-2018, 11:56 AM
Vote for NEW GROUP BUY - i'd love one of these

Shipper
05-02-2018, 03:07 AM
I bought this and then strengthened it up for the Large Case LSD.

Worth buying.

e24mpwr
05-02-2018, 10:09 PM
I'd be tempted to buy one. Wish we'd put this together before SharkFest...

foxcj
05-03-2018, 12:27 PM
Iím interested if you can make it happen.


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smashervt
05-20-2018, 01:17 PM
.

RSheiman
05-20-2018, 10:20 PM
Perhaps I am wrong but GI Jonas made these up a few years ago ( I purchased one for my M6) and while you all are interested, I have not seen him involved in any of the recent posts. I have a feeling requests are falling on deaf ears here. I suggest someone send him a PM to see if he is still here and if he can get this going again.... they are worth it.

94530inh
06-07-2018, 10:27 AM
Perhaps I am wrong but GI Jonas made these up a few years ago ( I purchased one for my M6) and while you all are interested, I have not seen him involved in any of the recent posts. I have a feeling requests are falling on deaf ears here. I suggest someone send him a PM to see if he is still here and if he can get this going again.... they are worth it.

I tried tracking him down... No luck

Shipper
06-07-2018, 07:31 PM
Here's mine installed. I also strengthened up the subframe.

There are some slight modifications as I run the e12 chassis and use a large case 3.73 LSD.

631233

631234

TowJamma
06-22-2018, 12:32 AM
Those are sweet mounts. Wish I would've found this board years ago.
My excuse is "I'm old".

ccwins
07-01-2018, 01:49 PM
Damn, I need one of these. If this is unavailable, what is my next best option?

Shipper
07-03-2018, 02:55 AM
There should be sketches on this thread somewhere. The bolt holes in the earlier sketches were in the wrong location. You could take the later sketches and get a fabricator to make them up. That's an option. There are simply no off the shelf items available. I'd take my car as well.

GI Jonas
07-03-2018, 01:20 PM
:rolleyes:rolleyes

Sorry guys!! This part of my life became little more than a distant memory for the past couple years. Life has been way too in the way of everything and Ive been working on other things in other departments to boot. I admit that I hav'nt even visited this forum in longer than I can remember and was shocked to see my thread near the top of the list. So look, my time is limited, but i am pleased to see the persistent interest in these quite honestly. I dont have the time to be on here promoting the mounts, however if you guys want to start getting the word out about another group buy, ill bite on this for another run!

I really dont think I can justify making this a go for less than 25 units. I do have some remaining center sections that are nearly done in a box, but for the most part I need to restart again. Go ahead and keep the thread alive and please speak up if you want one. I will make daily appearances from now on to keep track.

Also I very much apologize to all who's requests went unanswered, was never my intention to just drop of the earth.

Thanks Jonas.

grundlexhorse
07-05-2018, 07:45 PM
:rolleyes:rolleyes

Sorry guys!! This part of my life became little more than a distant memory for the past couple years. Life has been way too in the way of everything and Ive been working on other things in other departments to boot. I admit that I hav'nt even visited this forum in longer than I can remember and was shocked to see my thread near the top of the list. So look, my time is limited, but i am pleased to see the persistent interest in these quite honestly. I dont have the time to be on here promoting the mounts, however if you guys want to start getting the word out about another group buy, ill bite on this for another run!

I really dont think I can justify making this a go for less than 25 units. I do have some remaining center sections that are nearly done in a box, but for the most part I need to restart again. Go ahead and keep the thread alive and please speak up if you want one. I will make daily appearances from now on to keep track.

Also I very much apologize to all who's requests went unanswered, was never my intention to just drop of the earth.

Thanks Jonas.

I am very interested in purchasing one of these mounts! Will this mount right up to an e23 without any issues? Thank you!

GI Jonas
07-05-2018, 09:41 PM
God, its been so long now. I need to redo my research or wait for someone to chime in. Im pretty sure the answer is yes but I cant recall if the "to body" mounting area is different.

Shipper
07-05-2018, 10:26 PM
I had to modify for the e12 chassis and then modify again for the large case diff as its mounting point is off centre. Still, works fantastic in my car.

grundlexhorse
07-07-2018, 08:17 PM
either way, sign me up!

i found this:
Part 33171129786(Rubber Mounting) was found on the following vehicles:

E24: Details on E24
E24 633CSi Coupe, USA
E24 635CSi Coupe, USA
E24 628CSi Coupe, Europe
E24 635CSi Coupe, Europe

E28: Details on E28
E28 524td Sedan, USA
E28 528e Sedan, USA
E28 518i Sedan, Europe
E28 520i Sedan, Europe
E28 524d Sedan, Europe
E28 524td Sedan, Europe
E28 525e Sedan, Europe
E28 525i Sedan, Europe
E28 528i Sedan, Europe
E28 535i Sedan, Europe
E28 M535i Sedan, Europe

Here's the 535i diff mount. Cost: $197.53

Part 33171125290 (Rubber Mounting) was found on the following vehicles:

E23: Details on E23
E23 733i Sedan, USA
E23 735i Sedan, USA
E23 735i Sedan, Europe
E23 745i Sedan, Europe
E23 728i Sedan, Europe
E23 732i Sedan, Europe
E23 733i Sedan, Europe
E23 728iS Sedan, Europe

E24: Details on E24
E24 628CSi Coupe, Europe
E24 635CSi Coupe, Europe

E28: Details on E28
E28 535i Sedan, USA
E28 518 Sedan, Europe
E28 518i Sedan, Europe
E28 520i Sedan, Europe
E28 524td Sedan, Europe
E28 525e Sedan, Europe
E28 525i Sedan, Europe
E28 528i Sedan, Europe

And for the ///M purists, the Diff Mount for the E28 M5. Cost: $256.68 http://www.mye28.com/images/smilies/icon_eek.gif

Part 33171130900 (Rubber Mounting) was found on the following vehicles:

E24: Details on E24
E24 M6 Coupe, USA
E24 M635CSi Coupe, Europe

E28: Details on E28
E28 M5 Sedan, USA
E28 M5 Sedan, Europe

Shipper
07-08-2018, 07:17 PM
Go to my photos above.The bomb proof diff mount is brilliant. It could take well over 1000hp.

Anyone with an e12 chassis will need their diff out and crack inspections as the e12 chassis floor was week around the diff area. A bit like the E46 M3 boot floor cracking problems. I had huge cracks repaired and I stiffened up the floor prior to bolting Jona's BB-Diff Mount in. So a great replacement diff mount after checking your diff floor pan for cracks.

grundlexhorse
07-08-2018, 08:26 PM
That looks perfect! I'd love to have that so I don't ever have to replace it. It's way too expensive to buy the crappy rubber piece with no poly options.

foxcj
07-10-2018, 01:13 AM
I am definitely in for one if we can get enough interested to make it happen. Has anyone started a list yet?

TowJamma
07-11-2018, 12:44 AM
I am definitely in for one if we can get enough interested to make it happen. Has anyone started a list yet?

No, Lets do it, Do it. Does it go like this?

1
2
3 TowJamma
4
5
6
7
8
9
10

Copy, paste, and insert your name name in the appropiate number.
Or do we start a whole other thread?

foxcj
07-16-2018, 08:40 PM
1
2 foxcj
3 TowJamma
4
5
6
7
8
9
10

Next...



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grundlexhorse
07-18-2018, 11:55 AM
1 grundlexhorse
2 foxcj
3 TowJamma
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5
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10

Next...

Nullified
08-01-2018, 06:19 AM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mr. Nullified
5
6
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10

Next...



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grundlexhorse
08-05-2018, 07:56 PM
let's keep this alive!

GI Jonas
08-24-2018, 03:48 PM
I am still popping in guys.

mzilla6
12-01-2018, 09:40 AM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mr. Nullified
5 Mzilla6
6
7
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9
10

mzilla6
12-01-2018, 10:19 AM
https://drive.google.com/file/d/0B8CcYxTStmFfSi1mMk5oSGUyakk/view?usp=drivesdk

Mzilla6 plenum. Stroked n bored S38 B38.

Nullified
12-01-2018, 10:59 AM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5
6
7
8
9
10

I've taken myself of the list due to a change of plan

gemini533i
01-15-2019, 10:14 AM
If this works with a center mount diff like my 09/82 533i or
11/82 533i
I would like to be on the list if possible!
Also I would like to help gather interest

1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 Gemini533i
6
7
8
9
10

And if we only need 5 more people I'll make a post over on mye28 to remind people of this sweet setup. Im new to bimmerforums but You can find me over at mye28.com as subconscious533i. Can we confirm that this is still the current list?

TowJamma
01-16-2019, 01:40 AM
I don't know if this fits the 5 series. I can add I put a '89 6 series diff in my '80 7er, using the 6's cover and bushing.
May GI Jonas can give you an answer.
I'm am still in on this list.

gemini533i
01-16-2019, 05:32 PM
Cool thanks man maybe I will have to go a different route? I was just checking in because both my cars have center mount diffs. I haven't seen any options for strengthening this type of diff so I not sure. Maybe this calls for more research on my end. I've taken myself off list for now until i get more info.

1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5
6
7
8
9
10

Shipper
01-17-2019, 02:45 AM
I've run this diff mount with a centre mount sideloader and the side mount large case LSD off of an E34 M5. Works with both.

petr4271
01-17-2019, 07:11 PM
https://www.youtube.com/watch?v=5xGHeq6r8tU&frags=pl%2Cwn

DrScientist
01-19-2019, 05:01 PM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6
7
8
9
10

count me in as well.

E2heNnyHate
01-21-2019, 09:57 AM
Iíll get one bomb diff please lol ..still available? I have a 1985 bmw e28 535i if I buy it where would I buy replacement bushings or do you have and extra set I can buy with mount ?

E2heNnyHate
01-21-2019, 10:19 AM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6 E2heNnyHate
7
8
9
10

count me in as well.

gemini533i
01-30-2019, 10:29 AM
None of my diffs are side loading but I am in search of a lsd instead of my open. I'd like to use this diff mount if I could. But dont want to put myself on the list if it wouldn't work.

de Witt
03-10-2019, 01:09 PM
Put me down for one. LOL the OEM E28 M5/E24 M6 part is a nice $450.

1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6 E2heNnyHate
7 de Witt
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10

e24mpwr
03-10-2019, 06:35 PM
I've scanned, but I'm missing it - how much is the mount?

de Witt
03-11-2019, 04:51 AM
I've scanned, but I'm missing it - how much is the mount?

$195 was mentioned in the first post, but Ill be flexible with it.

Kinetik
03-11-2019, 08:21 PM
I'd like to be counted in for this diff mount

GI Jonas
04-04-2019, 01:41 PM
Still here guys. Have not been back in a while but glad to see this is still going. When I get some time I will be back and re check with everyone as I assume some people may have lost interest by now. Im a little hesitant to do a go of just 10 but that's what I said so Ill stick with it!

e24mpwr
05-05-2019, 08:27 PM
Bumping this

WazzaNZ
05-06-2019, 05:11 AM
I'm in too.

1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6 E2heNnyHate
7 de Witt
8 WazzaNZ
9
10 [/QUOTE]

DrScientist
05-13-2019, 12:18 AM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6 E2heNnyHate
7 de Witt
8 WazzaNZ
9 kinetik
10

Added kinetik to the list...

one more taker?

Anyone want two, just because?

DefactoM6
05-29-2019, 12:58 PM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6 E2heNnyHate
7 de Witt
8 WazzaNZ
9 kinetik
10 DefactoM6

Added kinetik to the list...

one more taker?

Anyone want two, just because?

DONE!

GI Jonas, let's do this!

bigperm206
05-29-2019, 04:58 PM
1 grundlexhorse
2 foxcj
3 TowJamma
4 Mzilla6
5 DrScientist
6 E2heNnyHate
7 de Witt
8 WazzaNZ
9 kinetik
10

Added kinetik to the list...

one more taker?

Anyone want two, just because?I'm hoping I can still get on this list. I'll take one.

11. bigperm206

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DrScientist
05-30-2019, 04:00 PM
Iíve got my checkbook out. To whom do I make this out?

DefactoM6
06-03-2019, 04:22 PM
Crickets... :-/

e24mpwr
06-03-2019, 10:49 PM
I PM'd him. If y'all are on BigCoupe, possibly someone there has contact info?

TowJamma
06-11-2019, 01:50 PM
Bump. Looking for GI Jonas

DefactoM6
06-19-2019, 05:05 PM
Hopeful but losing hope bump...

GI Jonas
07-03-2019, 07:13 PM
Damn guys...

First off I'm really sorry I ditched you all again. I had fully intended to keep my attention here but as many know, life gets in the way. Family health issues, owning a home, having a family in the first place! The list goes on. I am now catching a break and am happy to say that I am willing to take this on if you guys are all still on board. I completely understand if some minds have changed or if folks have found other solutions.

I will try to respond to my battered inbox of requests tonight and try to organize who's who and get some answers out. Once again guys, very sorry. I can't believe how much time has passed and how fast it has.

TowJamma
07-04-2019, 08:42 PM
Nice Jonas,
No hard feeling here, I'm glad you came back. Sure can relate to life happenings.
Ill restart and say I'm still in.
Appreciate your honour,
James

foxcj
07-04-2019, 08:46 PM
Glad to have you back.

Iím still in too.

GI Jonas
07-05-2019, 07:20 PM
Great guys. I've been thinking and I may handle this a tad different to make this easier. We can more or less stick with the plan of the group buy however we don't need to wait on everybody to re confirm as I know some people are on here less than others. Basically I'm thinking if I can just get 5 people to submit deposit ( half of total cost or pay in full, I'll leave it to buyers choice) I'll just go ahead and get materials and make a big run.

I'm not going to fart around with making a few dozen this time, I'm just going to go all out and make as many as I can stomach, so I should have them for as long as they are a relevant need. This way as people need them or as people who chimed in before can come in anytime and we'll get everyone taken care of.

My thoughts are also to set pricing at an even $200. I got a little taken back last time on including shipping, this is primarily why I'm bumping price a bit. So to keep it easy anyone in the lower 48 pays $200 total to get it to their door. Let me know if you guys need to know anything else.

- - - Updated - - -

Oh, also. Someone previously asked about the bushings. I can't remember the part # off hand but they are a very common, easily accessed bushing available in at least a couple different compounds. The info will be available to anyone who gets a unit and I may just post the info here if I remember.

- - - Updated - - -

TowJamma
07-08-2019, 01:12 AM
Payment sent. Thanks Jonas!

GI Jonas
07-08-2019, 09:26 AM
Thanks towjamma. Just going to take a couple more on before I start. Anyone putting in on this , simply submit via PayPal. After, please go ahead and verify yourself as paid here.

Please just PM me or anyone who has already submitted payment for my payment info.

Thanks again for the patience guys.

foxcj
07-08-2019, 07:27 PM
Payment sent.

GI Jonas
07-08-2019, 08:42 PM
I'm actually a bit pumped for this. Haven't done any creative / Fab type work for a while. Just go hum mechanic crap

GI Jonas
07-13-2019, 06:28 PM
Bump?.....I left you guys with crickets so I guess it's only fair 🙄

TowJamma
07-15-2019, 11:34 PM
Come on people, two up bump.

DefactoM6
07-17-2019, 05:50 PM
Tuned back in. PMing. I'll take two

GI Jonas
07-17-2019, 06:05 PM
Great Defacto, thanks. I think I'm going to get started this coming week. I don't want to keep those of you who paid waiting longer than necessary. I will fast line the first few to get them out to you guys rather than finishing the run. Thanks guys!

e24mpwr
07-23-2019, 06:55 PM
I'm sure somebody (maybe more than one) at SharkFest would want one (or two).

GI Jonas
07-23-2019, 09:48 PM
If all goes well, those of you who prepaid will be getting yours sent out the door by end of this week!

DefactoM6
07-25-2019, 10:19 AM
Wonderful news!

GI Jonas
07-25-2019, 10:07 PM
Mounts shipping tomorrow once balances are received!

GI Jonas
07-26-2019, 08:47 PM
Very sorry I dropped the ball today guys, got stuck in a relentless rut this morn so the mounts didn't make it out. They are my first priority in the morning!!

GI Jonas
07-26-2019, 10:01 PM
Defacto, Please PM me if you see this before you get my e-mail!

GI Jonas
07-27-2019, 12:01 AM
Nevermind Defacto, I got your info.

Nullified
07-27-2019, 04:56 AM
I cant wait for the next steps:

* people unboxing their upgrade and then installing it on the carand NOT forgetting to make pics.

TowJamma
07-31-2019, 01:52 AM
Part arrival Jonas. That is some superb workmanship.
Mahalo!

GI Jonas
08-01-2019, 10:01 AM
Glad you're happy Jam! ��

DrScientist
08-20-2019, 12:36 PM
oh no... did i miss the boat?

GI Jonas
08-20-2019, 11:14 PM
I can probably fit you in.:devillook

George Hill
02-07-2020, 10:23 AM
Jonas, Sent you a PM

e24mpwr
02-07-2020, 01:40 PM
Jonas - I missed the shipment-event, and hope some folks will post some pix, but I wanted to thank you for doing that run. I'd recommend you make some extras - I'm happy to take some down to SouthEast SharkFest if you'd like, too.

GG///M3
02-07-2020, 01:58 PM
Tuned back in. PMing. I'll take two

How are these working for ya bud?


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