e30 M50 swap exhaust manifold.

[e30325ic]

Does the m50 engine exhaust manifold work in the e30? I have heard conflicting reports. If it has to be modified thats no biggie just wanted to get the low down. I am planning this swap into a 1990 325ic rag top sometime in the spring and just trying to get things lined up.

[E30godz]

are you swapping in an M50 engine? or trying to put an M50 exhaust manifold on an M20?

[tranceguy]

I just got my engine in tonight. My exhaust manifolds clear the subframe by a good inch.

[Brew]

The manifolds clear fine. The forward-most downpipe will hit the CAB "lollipop". You can either use treehouseracing's CABs, or just have custom pipes bent up, or both, as I did. You will need to have some exhaust work done either way to connect the e36 system to the e30 system.

[e30325ic]

Thanks For the replies. I will porb have the e36 suspension allready installed by the time I get the the engine swap so the Lollipop shouldnt be a problem by them because I will used treehouse racings bushings for the swap.

[Beej '86 325es]

The manifolds clear fine. The forward-most downpipe will hit the CAB "lollipop". You can either use treehouseracing's CABs, or just have custom pipes bent up, or both, as I did. You will need to have some exhaust work done either way to connect the e36 system to the e30 system.

Are you talking about m50 or m20 dowpipes?

Speaking of which, I finished polishing half of my S52 OBD1 converted headers tonight. I can't seem to get a good picture of them, but it turned out awesome. Dremels rule!
:twisted:

[Brew]

The manifolds clear fine. The forward-most downpipe will hit the CAB "lollipop". You can either use treehouseracing's CABs, or just have custom pipes bent up, or both, as I did. You will need to have some exhaust work done either way to connect the e36 system to the e30 system.

Are you talking about m50 or m20 dowpipes?

M50 downpipes. I don't think m20 pipes will bolt up, but I could be wrong.

[Ryan Stewart]

I thought about doing that Beej but they will just turn brown again. Eventuallly I am just going to get some HIOPs.

[Beej '86 325es]

I'm sure they will, but at least I'm getting the weld residue off of them. I read some article in Roundel about E36 M3 headers, and they say those guys don't usually do headers, as the S52 ones flow plenty. Although, the HIOP headers do look nice.

[ed94r]

AFAIK:
S50 Manifolds: Better flow,heavy
S52 Manifolds: Lighter weight,less flow

Let me know if I'm wrong, cuz I just did the S50's on my conversion after some internal debate...

Ed

[trent]

AFAIK:
S50 Manifolds: Better flow,heavy
S52 Manifolds: Lighter weight,less flow

Let me know if I'm wrong, cuz I just did the S50's on my conversion after some internal debate...

Ed

Yes, you are wrong.

S50 Manifolds: less flow, heavy
S52 Manifolds: Lighter weight, Better flow

I fixed it for you :)

[Ryan Stewart]

The S52 headers are popular almong the swapping guys but for the price I can justify the HIOP headers just because of how much room there is and how visible they are. Call me a ricer (im sure trent will) but they would finish a clean engine bay. 8)

In reality I would get them to go along with the cam and headwork. Then the equal lenth headers would really help out. Plus for the makeup of shorties there is plenty of room.

[trent]

The S52 headers are popular almong the swapping guys but for the price I can justify the HIOP headers just because of how much room there is and how visible they are. Call me a ricer (im sure trent will) but they would finish a clean engine bay. 8)

In reality I would get them to go along with the cam and headwork. Then the equal lenth headers would really help out. Plus for the makeup of shorties there is plenty of room.

No i agree, if i had the money I would buy headers too.

[ed94r]

Not to stew the pot but...

One of the premier engine conversion guys (Mike at Sports&Imports) who has done over 20 conversions and sponsors some top club race and autocross guys (Bob Eveliegh and Tom Bleh) told me to go with the S50's for flow over the S52's.

Also, Terry Baker @ Atlantic Autowerks (6th or 8th @ the SCCA SOLO Nationals in an E30S50 SM car) who did my conversion, also told me to go w/ the S50's for superior flow.

The debate is over flow only. I realize the S52's are approx. 10 lbs less overall. I had the $$$ to do either one. I went with what the guys advised me for the cheapest/highest bhp. Do you have some verifiable dyno #'s to back up your belief? Not being nasty, just reeeally curious...

Ed Raymundo

[Ryan Stewart]

I dont have a back to back dyno comparison but the local racecarbuilder said that the primary difference was due to the materials. The porous nature of the cast iron gave rise to more trubulence in the exhaust.

I dont know if its actaully any power difference but I would bet that you wouldnt register more than 1hp difference either way on a stock motor. The fact that they weigh half as much was as good a reason as any to me. That and the S52 ones were free.