M5 3.6 headers to fit e23 M30 head

[SpunkyE30nOk]

first time poster in awhile...I usually just surf and read threads. Anywho I'm doing a M30 swap to my E30 and I'm still sourcing parts. I have 1 question. I'm buying some Euro headers from an e34 M5 3.6 and I want to put them on my e23 M30 motor. I found out recently that the bolt holes are different. I suspect due to the s38 being Dohc and the m30 being Sohc. I was wondering if I could have some flanges fabricated to make it for the s38 headers fit my m30 or any I better off reselling them and buying aftermarket performance headers?

[maxfield]

You can buy a header from the zone shop but it is pricey.

[SpunkyE30nOk]

yea..I'm in the u.s.a so buying parts from here would kick my arse when it comes to shipping. I really want to use the headers but I won't chop them and weld M30 openings on it either.....well if i get desperate enough to do it i may if its possible without developing exhaust leaks down the line

[Jon_Bmw]

I was about to mention the steering coloumn issue, then it clicked where you are from. There are more m30 headers kicking about for left hand drive motors from performance companies than RHD. I've yet to see an m30'ed e30 with a 6 branch.

[Toby_Unna]

You can get flanges machined from 10mm steel for around £30-£50 over here, that's how i made my turbo manifold (once someone else had drawn them in CAD for me, thanks again Gareth!)

wouldn't be hard to get those welded to the S38 manifold. I had wondered about doing something similar myself. a potential issue is that the port shapes will be different due to the 2/4valve issue, but the important thing is that the port spacing is the same.

[Robin-535im]

I'm in the US as well... with an e34,m30 and bought some s38/b36 headers from Germany for the same purpose. Stahl headers laser-cut some flanges for me per specs that I drew up and sent in. My heads are CNC ported so a tad larger than stock. Total cost was near US$85 with shipping, but call or email and get info from Jere (sounds like "Jerry") or his wife (forget her name but it's her email that they both use).

pic: http://picasaweb.google.com/bobritts/BM ... 8689664370

I wasn't clear in my communciation and they sent a 3-fer as in the pic, but I would have preferred individual flanges. I'm sure they can do both but the individuals may cost more.

HTH

- Robin-535im

[Toby_Unna]

those ports look quite a lot taller/squarer than standard

do you have the S38 manifolds installed yet, if so how did they improve sound/performance? seems like a cost effective mod to me

[Theo]

Do you think a RHD M5 manifold would fit in an RHD E30 M30 engine bay? I'd guess it would need alot of modifying? Karan needed a custom manifold for his S38 car, so I'm guessing that means the manifold was nowhere near fitting.

[Robin-535im]

those ports look quite a lot taller/squarer than standard

do you have the S38 manifolds installed yet, if so how did they improve sound/performance? seems like a cost effective mod to me

I still have to get them welded so I don't know yet. I just got my head back together after 5 long months of being apart... new Schrick 284 with all new rocker arms/shafts/springs/valve guides/ 8 of 12 valves. It's just begging to get that header fabbed up and put on! I had to ship the headers to the US from Germany, which added $100 to the $300 I paid for them, but even at that price it's hard to locate good M30 headers. Mostly I just like the curly-q pipes all tucked up inside there.

I also have a donor M30B35 intake and a set of s38B36 throttle bodies that have dreams of mating with each other... much like your install, but that one's a bit farther in the future. Still don't quite know if the coolant pipe junction will be clearable. I may have some detailed questions for you in the future!

[Toby_Unna]

Well here are a few answers, though some are specific to squeezing the lot into an e30!

http://www.e30zone.net/modules.php?name ... ic&t=49970

essentially the thermostat housing met an angle grinder, then a welder. the whole thing was a bit of a pain but it sounds nice and the throttle response is brilliant. they are a bit big though, it took a lot of careful and skilled fuel mapping to get it to run right at low engine speed/high load

[Robin-535im]

...it took a lot of careful and skilled fuel mapping to get it to run right at low engine speed/high load

That's part of what scares me... I'm pretty sure the stock ecu from the e34 won't have enough room in the "fuel trim" map to compensate and I'll have to go for a custom-programmed stock ECU or a megasquirt, which is just another layer of cost/effort that I'm not primed to at the moment. Perhaps when the newness of the cam and headers wears off Always gotta have something in the queue. Thanks for the link... and sorry to hijack the thread!

[SpunkyE30nOk]

...it took a lot of careful and skilled fuel mapping to get it to run right at low engine speed/high load

That's part of what scares me... I'm pretty sure the stock ecu from the e34 won't have enough room in the "fuel trim" map to compensate and I'll have to go for a custom-programmed stock ECU or a megasquirt, which is just another layer of cost/effort that I'm not primed to at the moment. Perhaps when the newness of the cam and headers wears off Always gotta have something in the queue. Thanks for the link... and sorry to hijack the thread!

no worries at all man. I haven't been around to ask questions so thanks for keeping it alive . I seen the pic of your flange, now dumb question from me. Are you going to weld the s38 headers to the flange then bolt it to the block?? I think I would have mine made like yours to save cost and keep it somewhat "simple"