Compression/Leak Down Test

[Xit40]

So I got my new AJUSA head gasket installed and everything seems good. I did a compression test after driving it about 50 miles and checking the head studs.

Here are the results in order 1-4: 180, 180, 187, 189. (9:1 CR should be 192 correct?)
I kinda messed up and forgot to hold the throttle plate open on the first 2 so that's why they are a little lower than the last two. I would have done it again but the o ring died, and by the time I got a new one the car had been sitting for a day. Oh well. Afterwards just because I could I did a leak down test. The results were 5% leakdown across the board. No rising or bubbling coolant.

So from what I can see everything looks good. So I'm thinking I should bust out my logger, check my fuel trims, and tune away. Sound about right to everyone? I guess I'm a little paranoid cause it was the second head gasket I had to put in since I had the motor built. I messed up putting the last one in (my bad). Followed the instructions to a T this time. Thoughts?

 

[DBordersX]

Sounds like you've got it pretty much under control to me. Tuning a 9:1 engine will be a little harder than an 8:1 but I'm guessing you knew that since you've got one in there. If you followed the directions to a T then you should be fine. What kind of HG did you go with?

Bust out that logger and tune away.

 

[turbodsm18]

A logger wont help you tune that much. Fuel trims are only for part throttle and for a 2g it doesnt detect knock.

 

[Xit40]

I used the AJUSA Head Gasket from Jackson Auto Machine as I stated above. I figured if they sell it it must work. Supposed to be good for 450whp and I'm not even close to that now so hopefully it works out. I still think I'm gonna go have someone do a coolant system pressure check just to be absolutely sure.

A logger is almost essential to tuning. Yeah I know fuel trims are only for part throttle, but those have to be good too for drivablity. For WOT I can use timing and o2 values. It's not the best way but I don't have access to a wideband and nor can I afford one right now.

The compression is supposed to be 192 psi for 9:1 cr on our motors right?