M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Swaps, Turbos, Buildups => Topic started by: jedens on April 09, 2012, 05:35:56 PM

Title: M42 to S42?
Post by: jedens on April 09, 2012, 05:35:56 PM
Hey Everyone I'm getting ready to buy an E36 3 Series with an M44 or an M42. Depending on the year I choose to go with, I've got a couple lined up.
Anyway to the point I Plan on buying a separate m42 engine that i can Break down and rebuild into an S42 or to get as close to possible but I've been reading and i know that there's really no realistic way to get the 90mm stroke from the camshaft; however, I know people use the 88mm crankshaft from the m47 diesel engine (with slight modifications) I just wouldn't know where to get one without going to the stealer.
so other than the obvious bore out the block and using s52 pistons what other things am I going to need for this project I'm trying to get a parts list going, a price cost, and how to even locate some of these parts.
Title: M42 to S42?
Post by: Warsteiner on April 10, 2012, 10:28:43 PM
The S42 had a 86.38mm bore and a 85mm stroke.
You need lots of stuff...lol
Solid lifters, better springs, 6mm valves, Super Tech
ported head,??
better headers,666 Fabrication
slide throttles with carbon fiber airbox utilizing either the 4 or 8 inj's.,Thailand
Engine Management off your choice??
Dry sump??
You can use the 88mm M47 crank, the dealer : custom machine work??
and S52 pistons, the web. custom machine work??
with 138mm rods,from Atomic Speedware :custom machine work??

Not sure what the pricing is now.
Lots more too..

Good Luck with the project..
Cheers,
~Ralph
Title: M42 to S42?
Post by: b_cyrus on April 11, 2012, 12:07:49 AM
I'm doing something similar, but good luck! Get ready for the expenses.. my ITB set alone with management alone cost 1200, and I still need to make the CF plenum.
Title: M42 to S42?
Post by: MLM on April 11, 2012, 01:46:50 AM
check my build thread for carbon plenum info. 1200 is a good price for itb and ecu.
Title: M42 to S42?
Post by: Massimo on April 17, 2012, 09:48:33 PM
It is not an impossible dream but will require money, skill and knowledge. To really replicate the S42 you would want to go for a lot of custom stuff, crank, lifter tray, yad yad.

The biggest issues is the cfm of the M42 head. You really want about 220cfm -240cfm but the best I have seen is 170cfm. I don't know what the S42 cfm was but I can bet there was some serious reshaping involved.

One thing I think everyone seems to not point out is the cooling passage for the S42. Water would go in through the front of the head, down through the pump, around the cylinders, up the exhaust side of the head, over the exhaust valves, over the intake valves and out the side of the head from 3 holes.

This is the usually way race engines work, as it has better cooling path and reduces hot spots allowing more timing advance. This is a good start that most DIY people can do, that all miss.

Home DIY with time, effort and knowledge should be able to get 260hp from the crank from a 2.1lt build.