Boost Leak Question

[tsunari]

Pressurized my intake and found a leak @ my TB. Fixed that and now it seems like the only place air is escaping is throught the head. Would this mean that:

1) the intake and exhaust valves are both slightly open when I had the system pressurized? or . . .

2) My intake valves aren't seated properly and the air is escaping through there and past an open exhaust valve?

I just had my head re-worked about 4 months ago . . . so which would be the most likely situation?

 

[gsx_tuner]

Run a compression check in each cyllinder, and then make sure it is in perfect time. Shops rarely do this right, that work on just "anything".

 

[tsunari]

Ran a compression check a few months ago and the #'s were pretty nice across the board. Although i plan on running another one this weekend just to check.

As for the timing, everything should be good so long as I haven't skipped any teeth.

Do the stock cams on the 4g63 overlap any? IE- both intake & exhaust valves are open @ same time for a period of time?

 

[steve]

Originally posted by tsunari
Do the stock cams on the 4g63 overlap any? IE- both intake & exhaust valves are open @ same time for a period of time?

Yes, I forget exactly how much overlap there is but if you search of overlap you might find my old post where we calculated what it was for various cams.

Try turning the crank to something like 30 degrees BTDC. There shouldn't be any overlap then. Unless it's past my bedtime, only one set of valves at most will be open per cyl.


Steve