99 E36 M3 LSx Build

[TipsyMcStagger]

I spent some time this weekend modifying the frame x-brace that bolts up under the car to clear the bell housing / oil pan.

Started by removing the interference

Then bent a non-M model frame brace that I had lying around for the clearance I needed

Cut it, fit it, and welded it up

Very nice. I was just thinking about this yesterday and how I don't recall anyone coming up with a brace solution in the past for an LSx swap.

I'd like to do this, eventually. I really need to learn how to weld!

Tipsy

[eurautodave]

i know how to weld...i need to get a brace and get to work.

[Inflame]

Very nice. I was just thinking about this yesterday and how I don't recall anyone coming up with a brace solution in the past for an LSx swap.

I'd like to do this, eventually. I really need to learn how to weld!

Tipsy

FastFabM3 (Sean) may be working on a solution and I'll be making modifications to my X-Brace also to clear the F-Body oil pan.

[ckpitt55]

^^ I know he had built one to fit the car in the stock configuration. Really like how he tied it into the transmission mounting points, I'll probably be doing something similar. The forward most of the 3 M8 mounting holes on either side of the tunnel could be utilized for this

Edit: Reread Sean's thread and got inspired to make a chassis brace from scratch, so I've got steel on the way to make that and my transmission mount. More soon.

-Chuck

[ckpitt55]

Been on a bit of a hiatus from the car. Had to deal with finals for the semester in grad school, busy with work, and I'm also in the progress of cleaning up a workspace to move into over the winter and hopefully keep things rolling better than they otherwise would in my driveway.

Before:



Progress so far:



In other news, I finished the transmission mount "cradle" tonight. I like how Schitzo made his so kind of adopted that concept. The tabs on the sides will serve as my tie in points for the crossmember and will help gain back some clearance for the secondary pipes that are going to be running through there. I don't have a press brake so had to cut all the pieces from plate. The baseplate of the mount is 3/8", everything else is 1/4".







Still need to decide how I want to do the crossmember for the car. I have some 1-1/4" DOM but might notch out some rectangular tubing instead - I'm thinking the latter would be a stronger design. Going to be working on that here soon.

I've also starting researching / planning out my exhaust system. Can't decide if I want to shell out the cash for pre-fabbed merge collectors or make them myself. Packaging is definitely going to be a challenge for what I'm going to try to do so I may end up fabbing them. Here's what I have so far, modeled in solidworks based on some playing around I did in Pipemax. The model serves a purpose - I'll be 3D printing a fixture to make the cuts on the mandrel bends for the collector's cluster joint.

[ckpitt55]

Finished the transmission mount this weekend





The connecting legs are .120" wall 1.75" DOM. I "ovalized" the tubing in my press so that the entire cross fit within the area of the mounting face of the "cradle" - and also slightly increases clearance for the exhaust. I should be able to tuck 3" up there and still be roughly flush with the frame rail.





Also finally got my catch can in, so I threw that on the engine. Need to get a 150 degree hose end for the dirty side inlet but ready to go other than that.

[ckpitt55]

Couple small updates...

Got the transmission mount in powder



Also started playing with exhaust related stuff. The long and short of it is that I convinced myself that 1-7/8" primaries will fit so ordered up the flanges and collectors from mandrel-bends.com, hopefully those will be showing up this week.

1-1/2" schedule 40 is a good mockup tool for this size as it measures 1.90" in diameter (pretty much 1-7/8"). A full fledged mockup can't be built from it though because the slip portion of the fittings interfere with each other and gaps the tubes apart too much. It was still useful for visualizing a rough concept for each cylinder though. I'm going to be doing a mockup in mild steel before ordering up the stainless since it's relatively inexpensive.

#1 will be busy



Couple of the others started.



I want to stay OBD-II compliant-ish and was considering these cats from magnaflow: http://www.summitracing.com/parts/mpe-99659hm. Anyone happen to have any experience with these?

[Schitzo]

Looks good Chuck.
I don't have first hand experience with the Cats you linked but do intend to use a pair from either on the links below. These were recommended to me by Rob (rao) so he may have more info.
http://www.magnaflow.com/02catalytic...UN%20PRE-OBDII

http://www.magnaflow.com/02catalytic...20SPUN%20OBDII

Looks like you have made some progress on the headers. I on the other hand, I'm still struggling with mock up. My copper tube idea didn't work too well....I might just wing-it lol.

[ckpitt55]

Looks good Chuck.
I don't have first hand experience with the Cats you linked but do intend to use a pair from either on the links below. These were recommended to me by Rob (rao) so he may have more info.
http://www.magnaflow.com/02catalytic...UN%20PRE-OBDII

http://www.magnaflow.com/02catalytic...20SPUN%20OBDII

Looks like you have made some progress on the headers. I on the other hand, I'm still struggling with mock up. My copper tube idea didn't work too well....I might just wing-it lol.

Thanks Robert

I contacted Magnaflow and those cats (along with most others on the market) are made out of 409, so corrosion resistance won't be that great.

I came across an alternative in 304. They're also 1" smaller in outer diameter (4" vs. 5") which will help with packaging. They're a little bit more expensive, but I'm probably going to pick up a pair of these: http://stainlessworks.net/index.php/...x-hi-flow.html

[ckpitt55]

Parts for the headers showed up so I'll be starting work on the primaries soon. All of this stuff is 304 stainless



I ordered a bunch of mild steel mandrel bends for mockup since they're relatively cheap and I won't feel as bad about making scrap out of it. Need to dial in my welder and practice on this tubing anyway, as it's the first time I've welded anything this thin with tig.



The merge collectors came out pretty nice. I ordered them from Columbia River along with the rest of this haul. Still kind of expensive but not nearly as bad as buying from other manufacturers.



Welded inside and out. Internals are blended smooth



I tacked on the expansion cones last night. With the anti-reversion cones and v-bands the collectors should be about 12" long. Packaging will be interesting but it looks like I'll be able to do it.

[lloydjoe]

Also got the mockup block and trans up and under the car - there are a couple bosses on the trans that are hitting that will need shaved for it to go higher, but a prelim check shows that I have pretty good alignment with the shifter hole. This is with the engine back against the firewall probably as much as it realistically can be. Anyone else using a magnum? Did you have to cut the tunnel at all for shifter clearance?

I am using a magnum in my car, did not have to modify the transmission bosses for clearance but I did have to modify the shifter opening some. The reason is because my transmission/engine is mounted further forwards than yours. I am using the vorshlag mounts. The fuel rails that I am using will not allow me to move it further back without modifying the fire wall.

Everything you have done looks awesome though. Great job.

[jai5]

Yea, do your "test" engine placement with the fuel rail and intake manifold on with the vacuum hose for the brake booster back there. It gets really TIGHT back there. So you will want some space.

[ckpitt55]

I checked all of those clearances before building the mounts. It's tight but everything fits fine.

Work on the headers to resume here shortly. Just got done hauling all my tools, parts, and car up to the shop this past weekend.

[ckpitt55]

Over the past couple weeks I've been busy installing a new garage door and opener at the shop, then getting the car and all my tools together and hauled up there. Finally at a point where I can start working on it again.



Last night I worked on setting the collectors in position under the car and managed to get the driver's side done. Took a while to find the sweet spot but I think I found something that will work while retaining decent ground clearance.

Using some existing threaded holes in the frame rails to build a positioning fixture from, some 3" exhaust clamps to hold the collector, then a couple pieces of square tubing welded together.





And under the car it looks like this:









A look from the side at ground clearance. For the most part I'm tucked up flush with the frame rail. Protrudes a little at the front but it is roughly flush with the bottom of the bell housing. I don't think I'll have any problems.



Hope to get the other side positioned this weekend and FINALLY start on the primaries. Thanks for looking

[ckpitt55]

I was able to make more good progress last night. Got the passenger side collector positioned and started work on the notorious driver's side header primaries.

It's not as close to the bell housing as it looks in this pic, must just be the angle.





Here's the driver's side for reference







Driver's side primaries



From below, snaking around the steering shaft. #7 will also be going on the outside with the other two. Going to be interesting getting that one routed



More soon

[bimerok]

Connect the spark plug wires. Make sure you're not touching anywhere... The one in the middle looks as a close call.

[bimmerg36]

Absolutely amazing attention to detail. Subscribed. Can't wait for more updates!!

[topfuelman]

Connect the spark plug wires. Make sure you're not touching anywhere... The one in the middle looks as a close call.

I agree! Not sure about what you have for clearance from the pics...but I can tell you from experience...The first set of headers we scratch built was a nightmare with #7 plug wire melting. The silicone would literally melt into goop and you'll get a misfire. You can't have too much air gap in the tight engine bay... That #7 will be the death of if you can't give it enough spark wire routing clearance...

also..something to consider is not using exhaust studs. To loosen and or remove a header for various future maintenance...like say removing trans for a clutch or changing a melted throw-out bearing assembly. There is a lot of heat that gets transferred to the t56 especially with the tight packaging...Trans oil temps will mirror engine oil temps in any hard use... I ended up putting an internal pump in the t56 and running a trans cooler as well for this reason.

[ckpitt55]

The spark plug wires all clear so far, I threw them on tonight. I'm probably going to end up getting a set with a 45 degree boot on them though to give me a little extra room. Also going to be using DEI heat boots.

I removed the treehouse fcab's tonight because they were giving me way too much caster up front, even with non-m control arms. With the tire sizes I intend on running I'd be rubbing the front bumper all the time, so I swapped in some centered bushings with the stock lollipops. This cuts into my header clearance but I had a feeling I would have to do this.....I tried to leave myself with some extra room with the collector positioning. I also threw on the starter motor - needless to say things got a lot more interesting on the passenger's side. It's going to be a challenge for sure but I'm enjoying it so far.

I agree! Not sure about what you have for clearance from the pics...but I can tell you from experience...The first set of headers we scratch built was a nightmare with #7 plug wire melting. The silicone would literally melt into goop and you'll get a misfire. You can't have too much air gap in the tight engine bay... That #7 will be the death of if you can't give it enough spark wire routing clearance...

also..something to consider is not using exhaust studs. To loosen and or remove a header for various future maintenance...like say removing trans for a clutch or changing a melted throw-out bearing assembly. There is a lot of heat that gets transferred to the t56 especially with the tight packaging...Trans oil temps will mirror engine oil temps in any hard use... I ended up putting an internal pump in the t56 and running a trans cooler as well for this reason.

The thought of at least putting a temp sensor in the trans had crossed my mind, but I will probably wait and see what happens before I worry about a dedicated trans cooler. Any pics of your setup for reference? Also how hard are you driving the car to be melting slave cylinders? I know the piston is just plastic but I can't say I've ever heard of that before.

[topfuelman]

Melting/distortion happens over time and the slave eventually fails. I used to do a lot of trackday sessions - 15-20 min hard driving. The internal pump deal was on a special build transmission with TR6060 or something style internals built by Rockland Standard gear. I got the same ratios as a ZR1 with a tall first, as well as much tighter 5th and 6th with less overall overdrive. It is a very nice box. I upgraded the build to include an internal pump from a vette box with external line fittings. Cooler is in the trunk with ducted fans...

Even with hi-temp spark boots and high temp 45 degree boots, with socks I had many issues with my number 7..so take every precaution in your design...even compromising flow slightly if you have to to gain clearance. I eventually went with a brembo pedal set-up unboosted to gain clearance and straighten out that number 7 primary as it exits the cylinder head.

The starters are also a real heat soak area with the long tubes...take precautions including reflective shields and leave as much air gap as you can...I've had a couple starters fail over time and used to get issues with the excessive heat causing the starter motor solenoid to not want to engage until everything cooled down sufficiently....

Ive run the lolipops and while they give clearance...they do cause a little rubbing on the fr bumper under lock with wide tires. I've trimmed away the bumper and inner edge of the fender - well I also run a widebody flare kit that changes things somewhat... Not really wide front wheels, and the most tire I've run is a 255 hoosier R6 front on a 9" wheel

Trev

[ckpitt55]

Trev, good info. Thanks for the input.

-Chuck

[ckpitt55]

The driver's side header is almost there, needs some tweaking to optimize clearances but I'll be ready to jig it and build it out in stainless soon. I'd consider what I have to be a pretty rough draft, more of less to prove to myself that 1-7/8" would work and get a general idea for shape. Looks like it will work but 1/8ths of an inch here and there matter - it is tight.

That being said - my hat goes off to anyone who has built their own headers. This is a challenge.

#1 primary looks like this. Clearances are tight between the steering shaft and motor mount plate, and also where the oil cooler lines exit the oil pan down lower.





Got #3 and #5 into the collector as well. Need to simplify the one but for the most part they're where they need to be. # 3 has tight clearances at the frame rail and also at my motor mount. The mounts being as tall as they are with OE style isolators certainly doesn't help. I may cut a relief of into the top of the mount to buy me some clearance there.



From below



Also got a start on #7. Super tight



Believe it or not, there is clearance there...albeit not much. Some light "massaging" of the frame rail might be necessary - really no idea how much engine movement I need to account for.



Here's a look from the side at ground clearance again. Can anyone comment on whether this will be sufficient? I've tried digging through pictures in other builds but it's a difficult thing to gauge. I'm not going to be super low - I'll be on 18's with 275s but this is probably as tucked as they can be with the quicktime bellhousing (or at least without clearancing it for the collectors).



I have some MTI plug wires coming with the 45 degree boot to hopefully help with wire clearance, changed a fitting on the oil cooler adapter and got some low profile mounting bolts for the motor mount to block connection. The oil cooler lines will also get fire sleeved and tucked in as close to the block as possible.

More soon.

[natem31995]

looks like that manifold is going to work nice. i take it you just have to take apart the steering shaft to instal the manifold. i would definitely wrap the manifold with header wrap. keep up the good work!

[bimerok]

Nice work!

As far as clearance go I would try to stay not lower than subframe for you headers...

[Maynor]

..I removed the treehouse fcab's tonight because they were giving me way too much caster up front, even with non-m control arms. With the tire sizes I intend on running I'd be rubbing the front bumper all the time, so I swapped in some centered bushings with the stock lollipops. This cuts into my header clearance ...

Treehouse now sells a centered fcab. Get back your header clearance. You'll need it.
http://www.treehouseracing.com/new/p...m-bushing-set/

I just dumped my offset Treehouse fcabs and swapped to the centered ones to keep the header clearance and reduce my front fender tire interference issue just recently.