Originally Posted by hemifire
I was looking at the parts catalog for the crossfire and came across a couple of intresting things. It lists the na compression at 10:1 and the SC compression at 9:1 . And I have also noticed that some of you SRT6 guys running larger crank pulleys are running about 22psi of boost. That seems extremely high for a car that has 9:1 compression ratio to start with.
So, what I was wondering is if any of you SRT guys have done a compression check and if so what were the results.
I'm going to do a compression check on my na as soon as i get the gauge from my brother.
The whole purpose is to verify the acual compression ratio on the two engines. I have a feeling that they are going to be identical. The short block part # 05114264aa has both egx(na) and egz(sc) listed as its application. Which means the limited and srt have the same short block. And I know they have the same heads so where is the difference in compression coming from?
According to the on-line parts manuals (Chrysler and MB) The 3.2L engine shares the same block, heads and valves - but that's about it - part numbers are different for the pistons - rods, camshafts, crankshaft...
The cylinder bore may be the same but I would guess that the piston domes, piston stroke, valves etc.. provide the difference in compression ratios.
Even if you could just "bolt on" a factory SC on the NA Crossfire - you won't have the same engine.