3.2 SS engine dyno

[joetiii]

I've read a few posts about upgrading a 3.0 to a 3.2 short stroke and am considering this as my next upgrade. I was hoping that someone on the board would have dyno results from before and after. Possible to scan and post if you do?

I am interested to know how the torque curve changes in this conversion. Since I have an 82 SC engine with PMO 40s, SSI exchangers and M&K 1out, the power comes on real good right around 3,000 RPM. This is ideal for my work at autoX. My only complaint is the engine runs out of steam at 6k when I'm out banging through the gears on backroads. So a bigger rush from peak torque to redline is desired without affecting low end grunt.

As I understand, an S style cam will make better power than stock SC in the high RPMs but the "S"s' shorter valve overlap will reduce static compression making for lower torque. Will the increase to 98mm slugs offset this loss? I'd like to stay at 9.5:1 compression and avoid going twinplug.

I also need to consider increasing the intake ports to breathe better up top. However, the tradeoff here once again is reduced low end response. hmmmm

[Paulporsche]

Try Gunter

[sjf911]

Here is a post to my first run. I don't have a before and this was the first tuning session on the dyno with an air temp of >100 F.

First Dyno Run

[joetiii]

With 10.5:1 and 964 cams, that torque curve is mighty flat from 3200 to 6000. I'll bet this pulls real strong and doesn't seem to run out of breath. I'm curious Steve, howz this compare before and after using your butt dyno? Is this street? AutoX? DE?

[sjf911]

There is no comparison from before and after. This car rocks. The only problem is you almost can't have "enough HP".

[Tom '74 911]

Steve -
Where in Idaho are you located? I'm in Hailey. Did you do the work and setup on your engine yourself? I ask because I'm gearing up for an engine upgrade at some point in the future and would like to have a more local connection/resource.

Thanks,
Tom

[sjf911]

I am in Boise. I have done all of the work with the exception of shipping the heads out for overhaul. I would glad to be of assistance. Let me know. It is a lot of fun and very rewarding.

[Tom '74 911]

Originally Posted by sjf911

I am in Boise. I have done all of the work with the exception of shipping the heads out for overhaul. I would glad to be of assistance. Let me know. It is a lot of fun and very rewarding.

Thanks Steve - it's nice to have local (somewhat) connections. While there's a few hands-on p-car owners here in the Wood River Valley, most I assume are not!
Tom

[joetiii]

Originally Posted by sjf911

There is no comparison from before and after. This car rocks. The only problem is you almost can't have "enough HP".

What racecar driver said "you have just enough horsepower when your wheels spin from one corner to the next" Mark Donoghue?