what do you think about this compression?

[RonRonTSI]

I just installed my motor and I did a compression test.

the result were 150 130 148 131 from belt to trans.

Shortblock (complete) with new front case, water pump oil pump, crower rods, arp mains, polished crank, wiseco race pistons, block is o-ringed clevite 77 bearings, bse kit. The head is freshly rebuilt. Now it is a fresh motor and I was told that it still had to break in to get an accurate compression test.


What should I be looking for? Do you think Im in trouble? or should I got with it?


Tell me what you think.

Thanks

 

[BoredDSM]

If you just installed the motor then yes compression readings are usually low. After about the first 1k miles you should see the compression at its highest after the rings have been seated properly. Remember to brake in the engine properly and to make sure u keep doing the oil changes till it's fully broken in.

 

[blcknspo0ln]

Well, make sure your engine is fully warmed up and you have the throttle wide open when you're doing the compression test. Oh, at least with Ross pistons, it's specified that non-detergent oil (I'm using ND SAE30 right now) to break in the engine.

 

[dsm-onster]

Intercooler piping should be disconnected from the throttlebody elbow, too. Although I didn't see too much difference in the results. . .

 

[illeffekt vr-4]

What CR are the pistons? I have 8.3:1 Wisecos and my compression was 160psi all across right after I built the motor. Now, 2k miles later its at 165-170 across the board.

 

[nightracer91]

Your compression will come up after engine break in, give it 500 to 1000 miles then recheck it....

 

[illeffekt vr-4]

Yes the compression numbers will rise a bit once the motor has been broken in but the problem is still the difference between the cylinders. If you look carefully there's a 20 psi difference between two pistons.