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DISCUSSION => Engine + Driveline => Topic started by: Gunni on January 29, 2007, 04:24:27 AM

Title: 20psi on M42
Post by: Gunni on January 29, 2007, 04:24:27 AM

Whats needed engine wise, assume I got everything else covered.

Title: 20psi on M42
Post by: 2002maniac on January 29, 2007, 01:19:12 PM

custom rods, low CR forged pistons, and a good headgasket should do it.

Title: 20psi on M42
Post by: sheepdog on January 29, 2007, 01:55:34 PM

I would consider o-ringing the block/head. Less gasket troubles.

Title: 20psi on M42
Post by: Gunni on January 29, 2007, 01:56:20 PM

Why diffrent rods aren´t they forged already?
would I be able to run lower compression only?
i.e thicker metal gasket, mill the pistons?

Title: 20psi on M42
Post by: bar73k on January 30, 2007, 05:53:29 AM

rods are fine to handle 20 psi

a steel gasket and lower compression pistons are all you need

you could probably get away with a standard headgasket.

its all in the tune, if you can tune the car well you dont need to go over the top

Title: 20psi on M42
Post by: nuvolarossa on January 30, 2007, 06:23:30 AM

I'm impressed of the power that M42 can put out with near stock internals!

not to hijack thread, but only for comparison:
What's need for make a M44 "20psi capable"? The rods are forged as m42, but crank is cast... it's important that the crank is forged with FI? How much psi M44's crank is capable?

thank you and sorry for hijack.

Title: 20psi on M42
Post by: Gunni on January 30, 2007, 06:28:25 AM

I wouldn´t think the cast crank be a issue as it is by far the strongest part of the engine

Title: 20psi on M42
Post by: nuvolarossa on January 30, 2007, 08:11:23 AM

Quote from: Gunni;18444

I wouldn´t think the cast crank be a issue as it is by far the strongest part of the engine

so, why all say that M44 can't handle boost, that M42 is better because it has forged parts... the only part that M42 have forged more than M44 is crankshaft:confused:

Title: 20psi on M42
Post by: Gunni on January 30, 2007, 09:00:17 AM

I´m sure it´s engine management issue,
as was with the M20 until people started taking control over the ignition
10psi used to be the max on a motronic system wich has been proven wrong numerously

Title: 20psi on M42
Post by: nuvolarossa on January 30, 2007, 10:56:47 AM

but with a standalone/piggyback and a perfect air fuel ratio, low CR forged pistons and eventually turbo rods it can handle 20psi as a M42, correct?

Title: 20psi on M42
Post by: Gunni on January 30, 2007, 11:17:17 AM

it´s possible that by using only lower compression trough a thicker gasket and right timing and afr´s you should be able to run it,

Title: 20psi on M42
Post by: kowalski on January 30, 2007, 12:34:04 PM

so a if someone were to build a stroker with an m44 crank they'd be fine to run >25psi?

Title: 20psi on M42
Post by: nickmpower on January 30, 2007, 03:10:39 PM

well i dont think anyones ever been ummmm brave enough to try

Title: 20psi on M42
Post by: zerofreez on January 30, 2007, 05:15:44 PM

You could get away with thick MLS headgasket technically.  If you get the CR around 8.5 or 9.0 to 1 you shouldnt have a problem.

I used to be into the turbo mitsubishi's and they had no problem running 20psi on cast rods and crank as long as you fed it good gas and your tune was good.

Title: 20psi on M42
Post by: 2002maniac on January 30, 2007, 07:07:03 PM

Quote from: nuvolarossa;18453

so, why all say that M44 can't handle boost, that M42 is better because it has forged parts... the only part that M42 have forged more than M44 is crankshaft:confused:

I have not heard anyone say that.  There is even a bolt on supercharger kit that alot of M44 guys use (DA)

Title: 20psi on M42
Post by: kowalski on January 30, 2007, 07:20:25 PM

Quote from: nickmpower;18473

well i dont think anyones ever been ummmm brave enough to try

so the i'm going to have to sell my m44 crank and find an m47 crank is what your saying... unless i want to be the test rat... which i really don't....

Title: 20psi on M42
Post by: nuvolarossa on February 02, 2007, 06:44:52 AM

Quote from: 2002maniac;18489

I have not heard anyone say that.

I read it more times in other forums...:)
I know that DASC exist, and midnight made a "kit" that was boosting 10.5psi on a m44 for 214rwhp!:D