the motor is a sleeved h22 w/ 9:1 compression and has about 630 breakin miles on it..(different loads put on the engine at different rpms...the highest rpm the motor has seen is 5000 rpms) oil changed at 50 miles than at 500 miles w/ new filter...vaccum is strong as all hell w/ 21 in HG at idle and 24in HG under load w/ no throttle (any gear)

i did a compression check last nite on the motor (cold)

numbers are :
cyl 1- 190 psi
cyl 2 - 160psi
cyl 3 - 170psi
cyl 4 - 160 psi


something is wrong here...anybody have any idea as to what??
are the rings not fully seated yet??
is my cylinder 1 just a freak cylinder?

the specs for a stock h22 w/ 10:1 compression i believe are 178max
135min

with no more than a variance of 28psi...so what gives????

 

Just an opinion but test it when the car is at operating temp not cold..

 

If 10:1 gives 178 then wouldn't 9:1 give (9/10) * 178 = 160psi?

 

Are they iron and what type of piston rings do you have and just a question but where did you get the sleeves from (darton) or could you give me the sight thanks.

 

Two things:

1) You did the compression test incorrectly. You must have the motor warm and at full operating temp before doing the test, or you will get incorrect results like you got.

2) You have not finished breaking in your motor. Sleeved motor use a rougher hone on harder cylinder walls, so the breakin is usually 1000 miles as compared to the stock rebuild's 500 miles. Dog on it for another few hundred miles before using the compression test's results as something to compare by.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LudeyKrus &raquo;</TD></TR><TR><TD CLASS="quote">Two things:

1) You did the compression test incorrectly. You must have the motor warm and at full operating temp before doing the test, or you will get incorrect results like you got.

2) You have not finished breaking in your motor. Sleeved motor use a rougher hone on harder cylinder walls, so the breakin is usually 1000 miles as compared to the stock rebuild's 500 miles. Dog on it for another few hundred miles before using the compression test's results as something to compare by.</TD></TR></TABLE>

thanks..

i again tried the compression test at full operatiing temp. and got the following results..

cyl 1- 190 psi
cyl 2 - 187psi
cyl 3 - 190psi
cyl 4 - 187 psi

guesss that was the problem... i will try once more at 1000 miles and if the compression doesn't go up any more than my ring should be fully seated...

as for the sleeves..they are iron (darton) got the from and installed by
ryan industrial in NJ...

 

Also try to hold the gas pedal down, and crank it 6 or 7 times.. if you didnt already do so....

 

I just put my motor back together. darton sleves, JE 9:1 pistons, JE rings, eagle rods. Arp studded. I als have a t3/t4 snail on it. What is the best process for break in? i put 60 miles on it today(started for the first time today since rebuild) I heard something about reving 6-7k is that right? and how long shoudl i wait to get in to boost? the highest i can boost now is 9 anyway but shoudl i stay totaly out of boost? I also have good vacume and all that.


Modified by MyVtec8yourV8 at 9:29 PM 11/15/2004

 

I bet cyl 1 was high when it was cold becasue it was hotter than all the rest (EGR).