Buddy of mines ap1 car he just bought off a guy says it's a built engine.

i ran a cr test. Cyl 1:155 cyl 2: 155 cyl 3: 160 cyl 4: 155
Now with those readings I'm thinking that's a good sign because that is low #'s for a stock block n if it wasn't built I dont think they would all be "down" or failing at the same rate n time.



So my question is what maybe are some of the possible static cr. It was built to?

My 11.5:1 static built H22 would ring out to 250
The stock f20/22 is 11.0:1 usually ringing out to 200's 210 I would say would be a freshy.

Thoughts? Built guys?

Now I just gotta get him to sell his cast manifold. I show him the way, cheee

 

Out of curiosity, are you using the same gauge on your friend's engine that you used on yours? I know I had a significant variance on my engine using 2 different gauges. If I recall correctly, I had similar readings that you observed on your friend's engine with one gauge. I then used a different gauge and got the typical numbers in the 200+ range for whatever that's worth.

 

240psi is typical new/oem gauge reading for the F20/f22. Not 200/210.

155psi is low for even a typical built lower comp engine. I have a 9.6:1comp built F22 with oversized 89mm pistons that read 225/230psi range. I suspect your gauge reads lower then typical. If your using that same gauge on an F20/22 and its reading 200, then add 40psi to your 155psi. Still low, but its potentially a used/worn out 9:1 comp motor. Couldn't imagine anyone would go less compression then that unless they just weren't informed properly. But im not convinced it is a built motor based on just low comp readings. Id need more evidence. Signs of an iron sleeve would be a more sure give away, since its a requirement for low comp pistons in this motor. No one to my knowledge makes a low comp oem/87mm FRM compatible piston for stock FRM liners.

 

It was the exact same gauge I have used on my built (wiseco 88mm 11.5:1) H, my F assuming stock, and his F (not sure) lowest of all on my gauge. Hell I did a buddy's stock H beat ta hell practically blown HG and they were 175-180's . I haven't done mine in awhile but it was higher then 200. I said 200-210 cuz I un-correctly recalled thinking of a stock H,. .....Hmmm.

If what u say is true, I suspect ur gauge reads high. Although there is alot of other variables at play here. Actual cal. And sea level etc.
Total #'s don't need "Kentucky windage" as far as I know I have a stock block and it rang higher then his. (Same gauge) And with Consistency like that between all cyl's, it's not sure proof but kinda hard to argue. Personally I would want more evidence to lol. The guy also said it was a gtx3076....Ahh nope, so some either cluelessness or just lies for sale. Thanks for your static and psi readings. Appreciate it.

I know all about the frm liners n forged pistons and compatibility issues etc. MAHLE doesn't make a lower static cr. For FRM? < Side thought no need for answer, anyways.

I believe me if I had a bore scope just verifying sleeves would be good enough for me.
the friend also thought about dropping oil pan. And thought that was a possibility to. I'm also gonna help him with his valve lash n to also see if it has the ARP cylinder head studs. < Although not pure proof still lol. Just seeing how honest seller was.


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Mahle does infact make 9.5:1 cr pistons for our FRM sleeves. That's what I had in my old built motor.

Test on your car or a known healthy engine and determine accuracy of readings. Or get a new gauge.... Then check the accuracy of it by checking a healthy engine. Lol