Daza33

Going by the second video I'd say you've got a popped head gasket. Does it blow white smoke when you rev it? Looked like it was blowing white from that video. White=coolant entering combustion chamber. Sounds dead average in the first video especially when it first fires. What is going on when you cranked it over, that noise was horrible.

Just rereading your original post and you said you connected the battery the wrong way. I would get that ECU checked to make sure you didn't fry anything inside when you through voltage up the wrong way considering your lack of spark. Also I would pin out the coil pack loom and make sure the coils that aren't firing are actually getting power from the ECU.

rb25det 8.5:1 cp forged pistons spool forged rods acl bearings stiffened valve springs 256 poncams hypergear atr43g3 .82 hybrid intercooler nismo 740cc injectors sard fpr 3" exhaust, 100 cell cat, nismo muffler z32 afm powerfc 290rwkw at 23psi dropping to 19. Need electronic boost controller to keep boost steady.

Hey mate keen on the swaybars and bov. Just wondering if you have the blanking plug to make it full atmospheric

Weather was pretty well perfect for painting. Low humidity. It looks like overspray however it is under the paint.

Hi guys, I resprayed my car over the christmas holidays, been there done it before and so has the old man. Car was thoroughly prepped and sprayed with 3M Jet Black acrylic paint. Today I washed the car and noticed white spots all over the car, under the paint. The surface felt rough so I went over it with a clay bar however the white spots remained. I'm just wondering if the paint not curing properly would cause this issue? I should also note that the car has clear coat applied to it as well. Just after some ideas before I start wet sanding to see if I can get the spots out.

Ok I'm going to dial in the cams this weekend, one quick question. Does anyone know how much adjustment can I get out of the standard intake cam gear?

thanks for the offer Ben but it's a s2 r33 motor. After doing some searching on the net after starting this thread I'm pretty confident the cam timing could be my issue. Everywhere I've read says retard both cams for top end, but have nothing down low which is pretty well what I have. Gunna suck adjusting it in the car but oh well live and learn

I pulled my lifters apart and cleaned them out, however I believe the springs shouldn't cause any issues with lifters. I was always under the impression that over revving the engine is what causes hydraulic lifters to shit themselves, because they can't keep up as opposed to solid lifters.

Oh no I had the car retuned after the rebuild. So GTSBoy you think degreeing the cams may solve the issue?

I understand that skimming the head and decking the block will increase compression, I was more getting at the fact that with the 8.5:1 pistons it would bring compression back closer to 9:1 After the rebuild the VCT solenoid crapped out and fried the VCT driver in the powerfc. I fitted a new solenoid and repaired the ecu and can verify it is working because I have disconnected the solenoid and the car drives like a pig.

Hi guys. So I rebuilt my rb25 last year after burning out exhaust valves and scoring a couple cylinders and ever since have had a large increase is turbo lag. I am running a Hypergear ATR43G3 with a .82 exhaust housing. Engine was rebuilt with: CP 8.5:1 forged pistons 86.5mm Spool forged rods Acl bearings Crank collar All new valves with stiffer springs Balanced and block decked + head skimmed Cometic MLS Gasket Added an adjustable exhaust cam gear but left it set at 0 Now I know that I have lowered compression but I find it hard to believe that such a small decrease in compression (after accounting for the decking and skimming of head) would result in my lag. I currently reach full boost of 21psi at 5000rpm, whereas before the build I made full boost of 18psi at 4000rpm. I inspected the turbo and found no damage, checked wastegate was sealing correctly, checked for vacuum/boost leaks and pre turbo exhaust leaks. The car is tuned with a powerfc, z32 afm and 740cc nismo injectors on 98 making 301rwkw. The only other change I have noticed since the build is that manifold vacuum has dropped from 24inhg to 16-18inhg, leading me to thinking that possibly the exhaust cam is retarded thus causing increased valve overlap, unless the drop in compression would cause such a drop in vaccum (I expect some loss of vaccum). I lined up the cam timing marks and crank timing mark correctly and triple checked they were spot on, however I didn't degree the camshafts. Does this sound like a possible cause of this increased lag? Or does anyone have any other theories as to what could be causing such a large increase in response. The turbo comes on hard but as a streeter it is far too slow to spool. I'll also add that I have checked that VCT is operating correctly. Thanks in advance

The fact that it has half the compression of the other cylinders means it's pretty much dead. Rip the head off and have a look at the damage. Can't really give any meaningful advice until you know what caused the damage

If an injector died you would have had a mad missfire, since no fuel is going into that cylinder. If it was partially blocked however, it would still run, just excessively lean and under full boost that means burned valves/det/f**ked engine. Do you have a wideband o2 sensor by any chance? If you do did you notice it running leaner than it should?

Pull the head off and have a look. Can't really blame the tuner until you know what went wrong. Even then good luck having them admit fault. Driving with twice the amount of oil it's meant to have probably didn't help anything as well

Valve stem seals tend to show when you have let the car sit for a bit then take off. Does it blow smoke on startup after leaving the car for a few hours? If not I highly doubt it's valve stem seals. Also I wouldnt be putting oil thickiner in an engine that takes thin fully synthetic oil

got a turbosmart bleed, same as before, holds boost perfectly. Ball and spring design

8.5:1 although I did get then cometic mls head gasket which may have dropped it a bit. Doing a standard compression test shows 170psi across all 6

So vct definitely works, so I can rule that out. Only other thing I can think of, and will check tomorrow, is that I changed the exhaust after the rebuild. It now has a nismo kit from cat back and now has a mid muffler and oval rear opposed to the cannon that it had before.

Ok thanks for the responses guys, I'll unplug the Vct and go for a drive this afternoon

Well 2 months ago I fried my power fc when the Vct solenoid died. Got it repaired and put a new solenoid in, I can see it switching through the hand controller. Guess I'll disconnect it and take for a drive. As for the wastegate, I've got close to 5mm of preload on it and have fabbed up a screamer for the internal gate, doesnt creep open it just snaps open and makes a shitload of noise. One last thing, if I were to adjust the cam timing is it going to throw out my tune at all?

Ignition timing is all good, 15 deg at idle. Vehicle has been tuned but the tuner didn't play with the exhaust cam gear.

Hi guys, so I am just after a bit of advice about this problem of mine. Last year I did a forged rebuild on my rb25 after burning out exhaust valves and scoring the bore. Since the rebuild my atr43g3 is 1000rpm laggier than before the build. I get 19psi at 5000rpm, whereas I used to get that at 4000 before the build. I am thinking it may have to do with my cam timing since I had the head skimmed and the block decked. I dropped the standard cams back in, lined up the marks but didn't adjust my exhaust cam gear so it is currently set to 0 degrees. The car sits at 18mmhg at idle when it used to be at 22-24mmhg before the build as well. Other than the turbo lag the car runs smooth, makes 301rwkw but only sees 220rwkw at 5000rpm, making it a nugget off boost. I am thinking of retarding the exhaust 2 degrees tomorrow, but thought I'd get your opinions before I do.

Hey guys just to bump this thread, this arvo was driving home and after getting off boost popped the engine control fuse. After getting home popped my PFC open to find one of the 3 large black chips was burned up. Anyone know if this is repairable, and if so where to take it in the Sydney area? Cheers

Hey guys, so just before my motor popped i got a code 34 - knock sensor. Since it is getting a forged rebuild I want to replace all my sensors and for the life of me cant find anywhere to get knock sensors from. Just wondering if anyone has any idea where one can find knock sensors.