SR20det compression question...please comment

[Boosted Gator]

I was wondering what is a good compression for a stock SR redtop. I did a check today and got the following.

CYL#1 - 122PSICYL#2 - 153PSICYL#3 - 134PSICYL#4 - 134PSI

Because everything is stock internals and such, excluding a T28 vs. T25 and intake and exhaust, are these numbers ok. This is my daily driver which I do not really beat on too bad, but I was wondering if it is getting time for new rings or anything else. The car runs really good and has no issues but I get nervous sometims. Let me know, thanks.

[ghx407]

Ideally, differences between cylinders should be less than 10psi. Your numbers are way past that. I reccomend you start saving/planning for a bottom-end rebuild so you don't get caught with your pants down.

[Boosted Gator]

How much will that set me back?

[IanS]

How was the compression test performed, was the engine warm/operating temp, was the throttle help wide open while cranking?

If you don't do a comp test correctly you wont have good numbers, with numbers like that, the engine wont run well at all, I would say re do the test.

[assassin7420]

I got 198-115-160-130 out of my KA and it ran fine. So thats not always true that the engine will run like crap.

[IanS]

I got 198-115-160-130 out of my KA and it ran fine. So thats not always true that the engine will run like crap.

If the compression test is done properly, and there is more than a 25 psi difference between cylinders, the low cylinder would be considered dead. Ive seen lots of dead cylinders, all have had run ability issues. What I have never seen, is an engine that exhibits no running issues that also has a dead cylinder.

[Boosted Gator]

I am not sure how the test was run, I just got the results. I will redo it my self and see if I get similar numbers. Regardless of dead cylinders or not, the car runs fine with no issues as far as driving, it does have a bit of a bump during idle but thats it. I'll let yall know.