Lancer 96 converted to Evo 4 GX

[mzeeshan]

Thanks buddy for informative details, yes the difference in each cylinder is around 1 to 2 psi only and we used calibrated digital compression tester as well as analog. The results were same, As its a low compression engine (Turbo) so the compression should be low instead of high.

The range of numbers in a compression test may differ depending on the equipment used. A different shop's equipment may show all cylinders to be around 180, or 190, or even above 200. It's the similarity between these numbers that affirms an engine's health.

For eg, one shop tells you the compression is 160 - 150 - 160 - 160.
This translates to cylinder # 2 as being weaker then the other cylinders.

On the same engine, a different shop would show 190 - 170 - 190 - 190.
Same thing, cylinder # 2 is weaker.

The deviation between the numbers matter, not the actual numbers.

[butwhy]

The range of numbers in a compression test may differ depending on the equipment used. A different shop's equipment may show all cylinders to be around 180, or 190, or even above 200. It's the similarity between these numbers that affirms an engine's health.

For eg, one shop tells you the compression is 160 - 150 - 160 - 160.
This translates to cylinder # 2 as being weaker then the other cylinders.

On the same engine, a different shop would show 190 - 170 - 190 - 190.
Same thing, cylinder # 2 is weaker.

The deviation between the numbers matter, not the actual numbers.

Not really....Equipment used doesn't matter unless the equipment is broken or something. However, altitude does matter. At higher altitude you will get a lower compression test reading.

Also, if all cylinders are screwed up, you can't tell that using this method.

The workshop manual should contain the actual range for the specific engine. The PSIs of compression test depend on the engine design.

Also, I think 150psi is a little high for this engine, maybe he's using after market dome pistons.

[N2O]

Not really....Equipment used doesn't matter unless the equipment is broken or something. However, altitude does matter. At higher altitude you will get a lower compression test reading.

Also, if all cylinders are screwed up, you can't tell that using this method.

The workshop manual should contain the actual range for the specific engine. The PSIs of compression test depend on the engine design.

Also, I think 150psi is a little high for this engine, maybe he's using after market dome pistons.

I think you have not done compression test on the same engine with two different compression testing tools. I have done compression tests from 4 different brand tools on the same engine and none have the same results. The main thing is to look for average readings in all cylinders. Altitude does not matter in this case as he is based in khi and all OEM measures are done at sea level. So that is all good.

Also if one has to extract the problem in any of the cylinders,leak-down testing is the way to go.

[butwhy]

I think you have not done compression test on the same engine with two different compression testing tools. I have done compression tests from 4 different brand tools on the same engine and none have the same results. The main thing is to look for average readings in all cylinders. Altitude does not matter in this case as he is based in khi and all OEM measures are done at sea level. So that is all good.

Also if one has to extract the problem in any of the cylinders,leak-down testing is the way to go.

Then there must be something wrong with one or all of the brands or the way the idiot mechanics are hooking it up to the engine...Also, rpm variance is there...(how fast was it being cranked)

[supraman2jz]

Then there must be something wrong with one or all of the brands or the way the idiot mechanics are hooking it up to the engine...Also, rpm variance is there...(how fast was it being cranked)

I have had my motor compression tested twice, same results as I wrote. Have seen numerous engines from friend's cars go through the same test, and guess what? Same results.

The RPM varies on each compression stroke, on every healthy engine, you are bound to loose some RPM on the compression stroke.

As a rule of thumb, anything above 130 is considered a good healthy motor. You have to maintain room for a 20 psi difference between each cylinder.

[supraman2jz]

I think we're deviating from the thread's original purpose, and it is now clear that the motor is in good health. Let the man sell his car. Good luck OP.

[mzeeshan]

Correct about the altitude but the test were done nearly at sea level (Karachi) with 14.64 Psia + as mentioned using stock original evo 4 with no mods.

Not really....Equipment used doesn't matter unless the equipment is broken or something. However, altitude does matter. At higher altitude you will get a lower compression test reading.

Also, if all cylinders are screwed up, you can't tell that using this method.

The workshop manual should contain the actual range for the specific engine. The PSIs of compression test depend on the engine design.

Also, I think 150psi is a little high for this engine, maybe he's using after market dome pistons.

[mzeeshan]

Thats ok buddy as long as we all know the correct information.... discussion is always healthy

I think we're deviating from the thread's original purpose, and it is now clear that the motor is in good health. Let the man sell his car. Good luck OP.

[mzeeshan]

bump.....

[mzeeshan]

Admin close the topic please ................ Thanks