Have not done any research on the subject yet. Thought someone might know easy answer. Will the CSI heads fit the reg 850 engine. Have a couple 850's and wanting to get more flow. Have access to cheap CSI heads. Thanks in advance.
By the way, I raced a friends 01 Viper gts last night on highway. He was pulling away, but not by much. I can hang with him if the turbos spool at the right rpms. Feels good to be that close, but damn feel so much better to be passing him!!

Email Ed here www.mwrench.com (http://www.mwrench.com)

Forced Induction is the only decent way to get those heads to breathe better....

Best to ask on Roadfly on the E31 board.

how cheap are the CSI heads?

Forced Induction is the only decent way to get those heads to breathe better....LOL!!! Excellent one liner. :stickoutt

By any chance would you be able to force my exhaust through the heads if you could drill the exhaust side into a bigger hole. It has worked on other cars and if done correctly idealy it should work on the M70 too. Just wondering if anybody as tried or even thought about that idea?

I believe you mean porting! It can't be as radically done on the M70 heads.

By any chance would you be able to force my exhaust through the heads if you could drill the exhaust side into a bigger hole. It has worked on other cars and if done correctly idealy it should work on the M70 too. Just wondering if anybody as tried or even thought about that idea?


I considered it while doing my 6L build. There is not a lot of material to work with and milling/porting too much will weaken the area. MWrench was able to do about 3~4 mm (IIRC) which did not do a whole lot of improvement. It is not the restricted by the opening area but mostly the angle.

http://www.itsystems.net/PersonalPics/850iA/V12HeadCutaway069.jpg

Forced Induction is the only decent way to get those heads to breathe better....


but he already has a twin turbo doesnt' he?

Ahmed303, that is a great cut away picture.

But what is that brass/copper looking piece that is part of the exhaust side?

Because if it is like a bolt or something like that you could machine it so that the angle is not so crappy by smoothing it out. I see what you mean by not alot of material to work with but even still it should be possible to smooth it out even some.

That "brass" piece is the valve guide. Can't do much to it without creating serious reliability problems.