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fatdog
10-14-2005, 10:51 AM
What would be the disadvantage to run an 11:1 compression ratio with an 88mm turbo?

What would be the optimum compression ratio?
Jim Monson
10-14-2005, 11:33 AM
What kind of fuel do you run? How much boost do you want to make?
fatdog
10-14-2005, 04:07 PM
I will probably be using C116.

As far as boost goes, as much as I can without spitting parts out the side.

How much boost do you think a 11:1 engine can handle?

What is your comp. ratio? and how much boost do you run, Jim?
Jim Monson
10-14-2005, 05:24 PM
Mine is around 9:1. I have run up to 30lb of boost on mine. I've heard rumors of guys running more compression. I would imagine you could run more compression, less boost, a little less timing than a 9:1 motor and it would work. :smt102
fatdog
10-17-2005, 12:05 PM
That is what I was thinking. It all boils down to static compression, right?
Jim Monson
10-17-2005, 04:32 PM
There's got to be a point where more compression is really bad. I really haven't messed with it too much.
Six_Shooter
10-18-2005, 07:57 PM
That is what I was thinking. It all boils down to static compression, right?

Dynamic compression and rate of pressure rise. ;)

The SCR is quite misleading from what I have seen.

There's also MANY MANY more variables to look at than just SCR vs. PSIG.
Remember PSIG (gauge pressure) is just a measurement of restriction, so 23 PSIG on a SBC will not be the same flow (CFM) as 23 PSIG on a SBF, or even another SBC for that matter. Cam(s), porting, intake design, even the headers can effect PSIG.

I use PSIG to compare changes on the same vehicle, mostly.