A rebuild for a 3.0 SC?

[rdane]

I will be rebuilding an 3.0 SC engine in the future. I have SSIs and a sport muffler now.

Like everyone I want more power, with a better lowend and a higher topend.

I am thinking a bigger set of P&Cs and cam but no carbs.

Reasonable? What would you do? I am looking for something around 240hp when I am done. Will a new topend do that?

[Wayne 962]

Short Stroke 3.2 would be the answer then. It's a bolt-on upgrade to the 3.2. The P&Cs are expensive though, and to get 240, you'd probably have to abandon the CIS...

-Wayne

[emcon5]

Some other thoughts here, which basicly agree with Wayne.

http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic;f=1;t=004403;p=1

You can also check out the 3.2L Short stroke thread from a few days ago.

Tom

[rdane]

OK, let me add a bit more. I have two 915 trannies. One is a close ratio gear set up and the other stock. I have a turbo brake up grade in the works, as well as oil cooling projects. But I was thinking if I stay under 240hp or so I could stick with the CIS and go with a 3.5L/twin plug (no idea there was a 3.7) set up on the original block. Knowing almost nothing about this past reading threads and a couple of suggestions from my shop what other options do I have?

I didn't want the added problems of a 3.6.

This are along the lines I thinking about. Anyone else using something similar?

"As far as pistons and displacement, Arnold Wagner, one of the owners of Andial, had a 3.7 liter, twin-plug sc cis motor in his personal car. I found this out a few years back when talking to him about cis. While I was talking about its weaknesses, he was discounting them and praising the system. He apparently loved cis and applauded it for it's inherent simplicity, reliability and ability to easily pass emissions day after day. "

[emcon5]

It is kind of funny that you say you don't want "added problems of a 3.6", but then talk about 3.7 twin plug CIS.

Displacement increases for 3.0 engines, in order of complexity/cost:

98mm P&C with stock crank (70.4mm stroke) 3.2 litres.
Stock 95mm P&C with Carrera crank (74.4mm stroke) 3.2 litres
Combination of 98mm P&C's and Carrera crank, 3.4 litres.

Larger than 98mm is possible, but you must machine the spigots on the case.

As to how much you can go with CIS, I don't think anyone really knows for sure (except maybe the guy from Andial). CIS is a mechanical system, with fuel delivery based on the position of the sensor plate. In other words, unless you can find out exactly how Mr. Wagner set up his fuel system and can replicate it, you are in uncharted territory. You may want to read this thread for a discussion of high HP CIS.

Tom