4.2 v6 + m112 Supercharger

g36 monkey · Oct 31, 2012

Orange 94 said:
Yes the 3.8 and the 4.2 are very similar and a fairly nice swap. But there is a few things that need to played around with. Mostly mixing and matching parts from both engines, like sensors.

The plate was from SSM (super six motorsports). And im doing meth because I cannot inter-cool. The supercharger heats up so much after the first pass that it retards the system a lot for the passes afterwards.

LilRoush had the first M112'd V6. If I remember correctly he never ran meth, and open tracked the car.

As far as PMing me, be my guest

LilRoush · Nov 3, 2012

Orange 94 said:
Yes the 3.8 and the 4.2 are very similar and a fairly nice swap. But there is a few things that need to played around with. Mostly mixing and matching parts from both engines, like sensors.

The plate was from SSM (super six motorsports). And im doing meth because I cannot inter-cool. The supercharger heats up so much after the first pass that it retards the system a lot for the passes afterwards.

Maybe I missed something. I was under the impression it wasn't tuned yet... but you are making passes with it? How much boost are you pushing? Like Jeremy said, I ran mine as an open track car and a daily driver - never had a heat issue (ran up to 18 psi on my built 4.2L with a ported M112 and 2.8" pulley). None of the cars I did set ups for needed cooling. Some have done it, but haven't seen much as far as long term profit from it.

I should probably read your whole build thread and then ask questions....

Orange 94 · Nov 5, 2012

LilRoush said:
Maybe I missed something. I was under the impression it wasn't tuned yet... but you are making passes with it? How much boost are you pushing? Like Jeremy said, I ran mine as an open track car and a daily driver - never had a heat issue (ran up to 18 psi on my built 4.2L with a ported M112 and 2.8" pulley). None of the cars I did set ups for needed cooling. Some have done it, but haven't seen much as far as long term profit from it.

I should probably read your whole build thread and then ask questions....

No, fair enough. It was in process of tuning by sending data log away to a person that has tuned this set up before. Unfortunately the data logger and tuner werent working very well together. We put it on the dyno and sent the dyno sheet off. I have a tune good enough to daily drive it during the summer, but it is pretty rich and at higher rpms really hurts the power. The supercharger gets pretty warm when I put my foot into it and when I put my foot into it again you can feel the difference because of the heat. Its running at 9. Want to tune it with the meth to save time and money rather than trying it without meth and then tuning it again.

If that makes more sense?

LilRoush · Nov 5, 2012

Yeah that does.
After reading your build thread, I saw you have the newer style "short" intake from SSM. I'm wondering if that is the difference in heat between Tom's boxed intake and mine. Mine was just tall enough to clear the stock fuel rail and not have to touch it - and wasn't notched at the front corner. My thought is that air flow on the slightly shorter box has changed vs the original design.

Was Justin (VMP) doing the tuning remotely for you?

If you are having heat issue, I agree it's killing your numbers. Just to give you an idea: With a 3.8L, my first sold kit made 330/309 @ wheels (5 speed) with 7 psi. We've seen as much as 335/350 @ wheels (auto) on an other wise stock split port. With the 4.2L most have pushed right up to that unspoken "do not cross with a stock bottom end" line of 350 rwhp with 6-7 psi. One thing we learned was go less boost and stop pulling out timing and the cars would make more.

Orange 94 · Nov 12, 2012

LilRoush said:
Yeah that does.
After reading your build thread, I saw you have the newer style "short" intake from SSM. I'm wondering if that is the difference in heat between Tom's boxed intake and mine. Mine was just tall enough to clear the stock fuel rail and not have to touch it - and wasn't notched at the front corner. My thought is that air flow on the slightly shorter box has changed vs the original design.

Was Justin (VMP) doing the tuning remotely for you?

If you are having heat issue, I agree it's killing your numbers. Just to give you an idea: With a 3.8L, my first sold kit made 330/309 @ wheels (5 speed) with 7 psi. We've seen as much as 335/350 @ wheels (auto) on an other wise stock split port. With the 4.2L most have pushed right up to that unspoken "do not cross with a stock bottom end" line of 350 rwhp with 6-7 psi. One thing we learned was go less boost and stop pulling out timing and the cars would make more.

Sorry for the late reply, Yes the difference of intake could possibly causing the difference. I totally forget who, but that name sounds very familiar. Also thank you for the tips! I'll let you know what I get for results in the spring!