Compression results, thought I would share.

[a_k]

The other night I went and did a compression test and I am really suprised. Here are the results.

1 - 120
2 - 100
3 - 100
4 - n/a I didn't feel like bothering with it after the rest of them
5 - 105
6 - 100
7 - 100
8 - 100

The engine has 124k on it but it ran strong or so it seemed. Oh well there goes the h/c/i plan. The good news is i'll have a fresh bottom end. I went and talked to the engine builder and it's not as expensive as I though

 

[HISSIN50]

Are you sure the tester's gauge works ok? Was the motor hot (not as important for hypereutectic pistons as forged, but still..........).

I would do a wet compression test to see how dramatically the numbers go up.

Good luck.

 

[a50sn95]

You held the throttle wide open during the tests, right...?

 

[VibrantRedGT]

You held the throttle wide open during the tests, right...?

Doesn't look like it. The motor can't be ice cold either. Also hook up a battery charger while doing the test.

 

[Zero Signal]

Yeah the battery will start to die and your results will show less and less pressure as you go. I made that mistake the first time around.

 

[ROLLIN5.0]

I wouldn't be too concerned with those results. There are a ton of factors that can give you low readings. The main goal is to see similar results across the board, which it looks like you did.
Brandon

 

[a_k]

You held the throttle wide open during the tests, right...?

I did not do that, I'll try that again, but I did test the compression on my 82 rabbit and its got 122 all across.... Hopefully it will go up a little

 

[igotyofire]

whats normal for our 9:01 compression stangs

 

[Green 94 5.0]

as someone above me said, uniformity with the numbers is more important than the actual reading to a point. try it again with the throttle open and the numbers should rise a bit.

 

[CManT1914]

whats normal for our 9:01 compression stangs

You're mainly looking for an average reading, not one in particular. So if cylinders 1, 2, and 4 are 140, while 3 is 100, something is fubar with cylinder 3.

FWIW, when I did my compression tests this summer, I got around 155 to 160 all around.

 

[mo_dingo]

whats normal for our 9:01 compression stangs

Ours are 9.5:1, fyi


And consistency in numbers is more important. Do it dry and wet, as that will tell you whether you have a head problem, or a ring problem, respectively.
Scott

 

[blksn955.o]

I have always seen like 8.8:1 or 8.9:1 as the comp. on the 94-95 GT's?

 

[mackey]

8.5:1

 

[blksn955.o]

/\/\/\

havre seen that too. I ahve never seen above 9:1


**ps kind drunk right now