To the Machine Shop I go!

[GT35Rm3]

I am droping my m50 block off at a local high performance machine shop in Atlanta tom.:

http://www.lamarwaldenautomotive.com/

These guys were highly recommended from a couple of you on the forum. (Thanks for the input Dadx2) I have talked with Lamar in depth on how he plans to proceed with what I want. They seem to do some good work and have a decent amount of experience with high PSI motor builds.

My plans are to assemble the motor myself. This is to save a little cash, and mostly gain the experience (Im gonna need some help in the futur, so Im counting on you guys :D). So I just need them to handle the prep work for future assembly.

Heres what I plan on having them do:

Acid Dip
Bore and Hone to 84.5mm
Line Hone the Mains
Deck the block
Oring (just the block as I am using steel orings with the stock HG)

Just a few questions before I drop it off:

Does any one have the specs in order to Line Hone the mains?

I read in another thread that somone, more specificly someguy, recommends having the machine shop remove the main oil drains and having them tapped and replugged. Can someone please elaborate a little more?

What spec's does everyone recommend/use (with success) for the o-ring? Lamar says he usually uses a .036" seat with a .044" oring. Which leave a .008" crush on the block/oring/hg/head combo. How does this sound?

Do you think I can handle the assembly without royally fucking myself? :)

Am I missing anything else?????

Thanks guys.

[Colby Colbs]

im sure you'll be fine just keep the beerz to a minimum lolz

[SiGmA]

Assembly shouldn't be an issue, post up if you need help. Good luck with the build.

[multiplex]

any reason you need to line hone the mains? I've yet to see a block that required this, unless you are going with some billet main caps

[SiGmA]

any reason you need to line hone the mains? I've yet to see a block that required this, unless you are going with some billet main capsI was wondering the same. BMW i6 blocks are made to a tight spec.

[e34m535t]

Ive read anytime you change the torque on the main caps, you want to line hone. I plan to do it when I add ARP Main studs.

[Colby Colbs]

I <3 billet mains!

[SiGmA]

Ive read anytime you change the torque on the main caps, you want to line hone. I plan to do it when I add ARP Main studs.This is prolly true, also prolly not needed as you don't need ARP Mains, stock bolts are a-okay.

[GT35Rm3]

So a line hone isnt necessarily needed? Even when swapping in an s52 crank from another motor?

[Colby Colbs]

As far as cranks go, they should be the same. Just dont mix up the caps!

[SiGmA]

So a line hone isnt necessarily needed? Even when swapping in an s52 crank from another motor?No, it shouldn't be needed. Make sure to keep the M50's bearing caps in order. Get bearings for the motor, measure them, measure the crank, and hope your clearances are good. They should be tho, its rare that a BMW crank is oversized or in need of machining.

[GT35Rm3]

Ill be using this to measure the clearance on the bearings:

http://www.plastigaugeusa.com/how.html

[5mall5nail5]

Make sure you get the main caps that came with that specific block and you'll be fine. Line honing is pretty expensive.

[SiGmA]

Ill be using this to measure the clearance on the bearings:

http://www.plastigaugeusa.com/how.htmlThat works fine, but its a good idea to measure the journals with a mic/bore gauge..

[GT35Rm3]

Make sure you get the main caps that came with that specific block and you'll be fine. Line honing is pretty expensive.

Ok good. I will not be line honing then, granted everything is within tolerance.


That works fine, but its a good idea to measure the journals with a mic/bore gauge..


Awesome info guys. Thank you.

Can anyone elaborate on the main oil drain taps?

[SiGmA]

The what?

[chikinhed]

Can anyone elaborate on the main oil drain taps?

I did that to my race prepped nissan engines I built. You are able to clean all your oil journals properly, especially after oil journal work. On the Nissan engines the main bearing journals from the main oil gallery to the main bearings that fed the rod bearings through the crank were enlarged to supply more oil at high rpm preventing oil starvation from centrifugal forces.

[Talperian]

Make sure you get the main caps that came with that specific block and you'll be fine. Line honing is pretty expensive.

My buddy recently bought a s50 crank and rods to throw in his m50. He didn't get the main caps from the crank/block the crank came out of, is this going to be a problem, what do we need to do to his m50 to prepare it for the new crank? Any machining necessary on the new crank?

[someguy2800]

Can anyone elaborate on the main oil drain taps?

There is a steel plug in the front and back of the block that plugs off the oil gallery in the block. Take those out so they can scrub it out at the machine shop. Drill a small pilot hole right in the center of it, then drill it all the way out with a 7/16" bit, and tap it with a 1/4" NTP tap. When all the machining is done install a 1/4" brass pipe plug with some thread sealer.

Bring your crank and bearings to the machinist and tell him to check the clearance and end play, only line hone it if it is out of spec, or you want more clearance.


My buddy recently bought a s50 crank and rods to throw in his m50. He didn't get the main caps from the crank/block the crank came out of, is this going to be a problem, what do we need to do to his m50 to prepare it for the new crank? Any machining necessary on the new crank?

No you have to use the main caps that the block originally had. No other caps will match up. The also must go on in the same direction and location as how they came off. No machining, just check the clearance and end play.


Ive read anytime you change the torque on the main caps, you want to line hone. I plan to do it when I add ARP Main studs.

It does change it but usually on the order of .0002" - .0003", which usually won't get you in trouble. Measure, measure, measure.

[GT35Rm3]

Thanks for the input someguy

[e34m535t]

This is prolly true, also prolly not needed as you don't need ARP Mains, stock bolts are a-okay.

Not needing them probably depends on how big your going. A 500whp build and a 750whp build will have some differences.

[Talperian]

No you have to use the main caps that the block originally had. No other caps will match up. The also must go on in the same direction and location as how they came off. No machining, just check the clearance and end play.



It does change it but usually on the order of .0002" - .0003", which usually won't get you in trouble. Measure, measure, measure.

Thanks some guy!

[jmargo]

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From Real OEM

[LukeG]

Can't wait Luke, I bet you are one excited SOB



anyone know of any good piston ring filing tools out there?

[GT35Rm3]

:D
Can't wait Luke, I bet you are one excited SOB



anyone know of any good piston ring filing tools out there?

I was really excited, untill my boss informed me that I am going out of town of the next couple of days :(....seems im needed...

It will just have to wait a couple of days.

+1 on the filing tool it will be needed.

Also, Luke, you wanna take a few vacation days and help me build this thing?

[LukeG]

Also, Luke, you wanna take a few vacation days and help me build this thing?


keep the beerz to a minimum lolz



This might be a challenge if I were to help you out.



But seriously dude, when are you planning on getting down and dirty with this thing? I'd love to see some warm weather lol. Plane tickets cheap?


Or you can get on some crack rocks, so that makes you forget about boost for a while, march will roll around and I'll CRUISE down to ATL and we'll knock this bad boy out. I will FOR SURE be going down there again this coming spring/summer. Those roads (cherohala skyway/deals gap) have me hooked. I decided to make it a "once a year must do thing"

[GT35Rm3]

This might be a challenge if I were to help you out.



But seriously dude, when are you planning on getting down and dirty with this thing? I'd love to see some warm weather lol. Plane tickets cheap?


Or you can get on some crack rocks, so that makes you forget about boost for a while, march will roll around and I'll CRUISE down to ATL and we'll knock this bad boy out. I will FOR SURE be going down there again this coming spring/summer. Those roads (cherohala skyway/deals gap) have me hooked. I decided to make it a "once a year must do thing"

You been hittin the dove Luke, lol.

Im sure you miss the boost man. But just think about how much power your going to be putting down in the summer! Your gonna get some more tuning done with TRM right? Going blow thru? What else?

Im gonna start banging this shit out soon man. Im prob gonna order everything I need soon. You wanna help me get a list together? :D I think its about time to rip all the bull shit off my car and start over. :buttrock

[LukeG]

Lol what does hittin the dove mean?


I'm not sure if I want/need to hit up trm again. I just got my boost issue fixed before I pooped the clutch and the car felt like a new animal. Thats me talking now, we all know what happens after a month or two of solid power. I'll want more I'm really aching for a e30 m3 project.


And I'll fly down on the wednesday, we'll see what parts we need. Overnight them from japan and pound everything out by sunday night. Lol, you know I'm there to help in anyway I can man. I'm actually quite serious about flying out to help depending on work/etc. I mean, I'm getting a fresh batch of vacation days in a little bit here :D Tell me what you want to do, what you currently have and we'll come to a nice conclusion of what you need to get!

[someguy2800]

anyone know of any good piston ring filing tools out there?

for ease of use you can't beat a file in a vise. Put a good clean file in a vise pointing straight at you. Hold the ring with one hand on either side of the gap and hold it straight on with the file. Press both sides of the gap against the sides of the file and stroke back and forth. When you got the gap where you want it gently debur the edges and your good to go. Take mabey 30 minutes and perfect results. The power ring filers are nice but a bit aggressive if your not used to them.

[GT35Rm3]

Lol what does hittin the dove mean?


I'm not sure if I want/need to hit up trm again. I just got my boost issue fixed before I pooped the clutch and the car felt like a new animal. Thats me talking now, we all know what happens after a month or two of solid power. I'll want more I'm really aching for a e30 m3 project.


And I'll fly down on the wednesday, we'll see what parts we need. Overnight them from japan and pound everything out by sunday night. Lol, you know I'm there to help in anyway I can man. I'm actually quite serious about flying out to help depending on work/etc. I mean, I'm getting a fresh batch of vacation days in a little bit here :D Tell me what you want to do, what you currently have and we'll come to a nice conclusion of what you need to get!

Some local slang for smoking crack.

Im gonna get something writtin up to help me get my head around what I need, and what I have. Ill send it out to ya when I get it done. Thanks dude.

[A4RingedONE8T]

So a line hone isnt necessarily needed? Even when swapping in an s52 crank from another motor?

If you going from OEM main bolts to ARP main studs then yes you should absolutely do a line hone as they apply torque differently. If swap is bolt to bolt then its not always needed but never hurts to have the machine shop spec it out and be sure. Better to check and/or have it done now then find out it was needed later :)

[LukeG]

I have arp mains and my mains did not get line honed.

[GT35Rm3]

Did you torque them to the standard spec?

[LukeG]

Lol to be honest with you I don't remember. I believe so, unless ARP provided other tq specs in the box.

[someguy2800]

If you going from OEM main bolts to ARP main studs then yes you should absolutely do a line hone as they apply torque differently. If swap is bolt to bolt then its not always needed but never hurts to have the machine shop spec it out and be sure. Better to check and/or have it done now then find out it was needed later :)


we allready covered this. it usually changes the housing bore about .0002" - .0003" Keep in mind that about 20% of machinist can actually do a line hone without fucking it up worse than it was before. It should be avoided unless absolutely necessary.

[DADx2]

Lol to be honest with you I don't remember. I believe so, unless ARP provided other tq specs in the box.

That is correct. My ARP main studs are torqued to the spec that was provided with the studs. Mine has not been line honed and so far no problems. (10k miles @ 532whp)

[LukeG]

thats what we did then, thanks for clearing that up.