1Gina2G
10+ Year Contributor
- 810
- 2
- May 6, 2011
-
Beaufort,
South_Carolina
ill try to make this short as i can with detail. what i have is a 2.4 sohc 4g64 n/t engine that is now been rebuilt and turbo'd, me and my cousin (cousin for the most part) did the block entirely, cleaning, new bearings and oem piston rings, got the pistons and everything looking new. gapped the rings according to the manual, oem headgasket. had the machine shop redo the head completley and this engine uses headbolts rather then the studs the 4g63s use, torque to yeild, so i just replace. anyways on the the issue;
can not figgure out if our piston ring job was actually good enough or not even though the car drives good for the most part, but sometimes does feel notchy, hard to explain.
-excessive blow by out the crankcase, the valve cover is just like the dohc 63s, 1 breather port on the side that works both ways, supposed to be breathing in at idle, mine exhausts out.
-pcv valve works fine
-some air not much from dipstick/oil fill, hard to say
-reading good vaccum -20
-perfect air/fuel ratios at all times on wideband
-all cylinders make perfect compression since right after rebuild till now 190-210 for the 4g64
-no oil consumption or loss in anway, actually rebuilt because of oil consumption.
-leak down test has air come somewhat back into the area of the injected cylinder...this is of course with the tested cylinder being a tdc of the compression ect.
car drives without issues really but i wish i knew why i have this much blow by and how bad is the block actually since it seems to hold power at 14 psi just fine with stock 4g63t turbo parts and ecus, small 16g turbo rebuilt by the way on stock 450cc.
anything else i can check? i think my exhaust may be to small or something just an aftermarket stock gst exhaust kit i got from someone. i head exahaust flow may have some relation to blow by pressure, not sure. thanks all.
can not figgure out if our piston ring job was actually good enough or not even though the car drives good for the most part, but sometimes does feel notchy, hard to explain.
-excessive blow by out the crankcase, the valve cover is just like the dohc 63s, 1 breather port on the side that works both ways, supposed to be breathing in at idle, mine exhausts out.
-pcv valve works fine
-some air not much from dipstick/oil fill, hard to say
-reading good vaccum -20
-perfect air/fuel ratios at all times on wideband
-all cylinders make perfect compression since right after rebuild till now 190-210 for the 4g64
-no oil consumption or loss in anway, actually rebuilt because of oil consumption.
-leak down test has air come somewhat back into the area of the injected cylinder...this is of course with the tested cylinder being a tdc of the compression ect.
car drives without issues really but i wish i knew why i have this much blow by and how bad is the block actually since it seems to hold power at 14 psi just fine with stock 4g63t turbo parts and ecus, small 16g turbo rebuilt by the way on stock 450cc.
anything else i can check? i think my exhaust may be to small or something just an aftermarket stock gst exhaust kit i got from someone. i head exahaust flow may have some relation to blow by pressure, not sure. thanks all.