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Pig
11-01-06, 21:14
Used the search with no luck.

After i had a turbo blow mark did a compression test for me. He said the results came back at 96% for all of them, and that this was really good.

Can someone please explain what this means.
cheers
Jake
11-01-06, 21:18
"Really good" is preferable to "Really bad"


HTH
Pig
11-01-06, 21:22
phew, im so pleased you cleared that up for me. thanks :D
Jake
11-01-06, 21:27
You're welcome Sonny. You don't get to twelve thousand posts without learning a thing or two.
:sly:
merckx
11-01-06, 21:30
An engine compression check will tell you whether pistons, rings or bore, are worn or damaged.

It'll tell you if the inlet and exhaust valves are burned or failing to seat properly.

It can even tell you if the cylinder head gasket has failed.

96% is near enough perfect, as you put miles on the car this figure will slowly drop.

Having the same figure for all 6 cylinders means they're perfectly balanced in terms of compression which is what you want.
Pig
11-01-06, 21:32
Good stuff.Great result for 100,000miles then! thanks!
Pete
11-01-06, 22:34
Err...yes!
Lucifer
12-01-06, 09:01
Well depends on what he meant.

He could have meant 96% of the reference cylinder. Numbers would have been more help.

http://www.mkivsupra.net/vbb/showthread.php?t=55174
JohnA
12-01-06, 10:25
"Really good" is preferable to "Really bad"


HTH
Really?:limp:

What exactly is the meaning of a percentage in a compression test context?
(answer: not much)
Percentage is only used for leakdown tests.

Compression tests provide a pressure figure for each cylinder, along with the test conditions (such as warm/cold engine, number of crank turns for full figure to settle)
Pig
12-01-06, 10:37
Maybe he was talking about a leek down test?? Ill ask him next time i talk to him and see what he says!
Terry S
12-01-06, 10:39
he will have done a leakdown test John.
Lucifer
12-01-06, 10:39
If so 96% is a good result for a 100k Engine.
Pig
12-01-06, 10:46
Cheers terry, that explains that then! lol. (what a penis i am)

What what does a leak down test mean and how good is this result?
Lucifer
12-01-06, 10:48
http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm
Pig
12-01-06, 10:55
Cheers! :D
JohnA
12-01-06, 11:18
96% leakdown on all cylinders is fecken good.
Not far from race-spec in fact.


PS
The link posted above is a bit off. This guy suggests on a 4-cyl to do 1-4 and 2-3 togethers, as they both hit TDC together.
Not good for leakdown though.