So i did a compression test and just double checking myself (always good to get a second opinion. First off removed all plugs and disconnected injectors. Started on the pulley side and went across towards the distributor. results were as follows.

#1. 196psi #2. 200psi #3. 200psi #4. 210psi

again number one is closest to the main pulley and the number four is closest to distributor.

What do you think of these results.. Just asking for an experienced second opinion.

 

Do it over again and keep all the plugs in except for the one you are doing the test on. If its still off by ten then drop a tiny bit of oil in the cylinders and retest

 

BTW its a bone stock B16A

 

no other comments???

 

come on ... Someone has to have some input.. this is a simple issue... just asking for a few opinions!!!

 

seems like good results to me

 

from mithchell specs are 220psi....with no more than 28psi variation between cylinders.

so you are plenty good on compression.......and you are within spec on variation. looks good.

i would run it again and try squirting some oil in each cylinder just before you test it. running a wet test and a dry test will give you some more perspective on the condition of the engine.

although i disagree with System Lord........compression tests should be run with all plugs out............unless you have another angle on it System Lord. im open to other ideas.

 

whats the problem??

your numbers are just fine.

 

I guess my angle is that a cp test imo should be done with the plugs in because it pulls a reading with a full and complete stroke, I feel more comfortable doing it this way for a more accurate reading and make sure you have wot while testing. Who knows I may be doing it *** backwards but all of my builds are 100% reliable.

 

numbers look good to me.

 

Your variation is in spec as well gl.

 

Question for System Lord and newtron63h: Will results vary when pulling all plugs vs. only pulling one plug at the time? I have always pulled one plug at a time, maybe I'm completely wrong.

 

Haynes manual says remove all plugs disconect ignition and disable fuel and block throttle wide open for compression test.
Not really sure it makes a great deal of differencs.

 

You can do a compression test either way, all plugs out or just one at a time. Since each cylinder and combustion chamber is sealed separately from the next it would not cause a change in the number for the particular hole being tested. Proof of this would be to do the test back to back each way and the numbers will be the same.

 

They're + or - 5% from the standard 200 so i would call it good....no need to retest

 

the purpose of removing all plugs and doing the test at WOT is to remove as many loads from the engine is possible(turning the engine with all the plugs out is much easier than with only one out) this gives you a more accurate reading. WOT is so that there is nothing blocking the air going into the cylinder......yet again for a more accurate reading. all plugs out i believe is more critical than WOT. ive tested one cyl twice at closed throttle and then twice more at WOT and the reading did not change at all.

 

You need to remove all of the plugs actually. Be sure to ground them as best you can while testing. The only cylinder that should be 'plugged' is the one with the compression tester. Then crank at WOT for about 10 cycles and check where it reads

 

My results were 245-240-245-240, so I'm well within the limits, I redid the test with all plugs out and got basically the same numbers, each cylinder within about 3 psi of the original test. I was told my motor has ITR pistons when I bought it. It is a GSR block/head, did one of those compression ratio calculators (c-speed racing) and it puts me at approximately 11.5:1 give or take a little for which head gasket is being used. Anyway, does this sound about right?

 

you DO COMPRESSION TEST when the motor IS COLD to the TOUCH. not when warm at all.