ProZac wrote:New intercoolers are pretty cheap now a days... A friend had his VQ30DET powered 180sx tuned at NZEFI the other day, they found a pretty big pressure drop across his intercooler also. They replaced it with one they sourced and it apparently cured heaps of issues.
For $300 you'd get a pretty top-spec cooler in about the same size, probably wouldnt have to modify much to fit it.
The pressure drop would make sense, as even though your manifold is seeing 15psi, your turbo is probably working outside of its efficiency range and just generally buggerising everything up...
Fuck man, I bet it still goes like a bloody rocket ship though :)
Its a shame NZEFI didnt test my car for pressure drop. Ill have to ask them why.
Getting a good cooler should be an issue but fitting it could be tricky...
yeah mate, its still a quick car as is, can't wait until its sorted!! :D
perrinsohc wrote:All the best for the straight pipe, I'm pleased to here that you have another potential problem to fix. It's the worst when you can't figure out whats wrong. And better still you fixed the timing that may have been overlooked if you hadn't been investigating
Very true mate. Its not ideal but having problems like this make you check everything.
1984 Sigma Super, Turbo Wagon
1990 GSR-VR 50,000ks
1984 GSR II 4G63 302kw atw at 24psi
can of engine start and spray it round the manifold with it running, if the motor revs up theres a vaccum leak
87 GSR-V, Factory DASH, Rebuilt bottom end with arp rod bolts and balance shafts removed, head reconed with 3 angle valve grind, TD05 housing machined out to take Garrett T4 internals, rebuilt and cryoed gearbox
that'll only show up a big crack, not one that opens only under boost, i've had that happen before. you need to pull the manifold and pressure test it at a radiator shop if the carby cleaner method doesnt show anything up..
Fibreglass airdams $370, fibreglass front bumpers $260, reco drag links $165, alloy radiators $925 (unpolished), h/l switch rebuilds $125, all plus freight.
Coxs Automotive (07)54433507 3/5 Service st Maroochydore Q
Or if the other half will let you... fill up the bath, block one end of the manifold, seal up the other end and pump air into it and see if air bubbles come out?
5psi is quite a bit!
That's as much PSI as my old starion was running before it got the rebuild and the turbo sorted!
Sold - 1987 Mitsubishi Starion GSR V DASH
Current - 1995 Subaru Legacy TT SW
- 1983 Mitsubishi Starion
bridgey wrote:can of engine start and spray it round the manifold with it running, if the motor revs up theres a vaccum leak
Tried that, and nothing.
Emailed the guy at NZEFI and he said they pressure test the intake system before each dyno tune. But has offered to recheck it agian.
The starion goes in to have the respray (to fix the earthquake damage) on monday so Ill have to wait a while.
Its all very odd!!
1984 Sigma Super, Turbo Wagon
1990 GSR-VR 50,000ks
1984 GSR II 4G63 302kw atw at 24psi
find a work shop that has a smoke machine , it pumps colored smoke in to ya intake and (b4 turbo) and shows up any leaks . idealy while its doing a dyno run - like red said some things may only show when under a decent load
Wait, before that actually, just swap them around where they are at the moment and see what kind of reading they give, that'll tell you if they're reading accurately or now.
ProZac wrote:Wait, before that actually, just swap them around where they are at the moment and see what kind of reading they give, that'll tell you if they're reading accurately or now.
Now that's smart thinking :) :beer
I've had mine since 03 07 92
85 JB 2323cc DOHC 4G63
THE OLDER I GET THE FASTER I WAS
GROWING OLD IS MANDATORY GROWING UP IS OPTIONAL
ProZac wrote:Wait, before that actually, just swap them around where they are at the moment and see what kind of reading they give, that'll tell you if they're reading accurately or now.
Now that's smart thinking :) :beer
Yip tried that. Got the same results. Me not silly :)
1984 Sigma Super, Turbo Wagon
1990 GSR-VR 50,000ks
1984 GSR II 4G63 302kw atw at 24psi
TOMSUN wrote:Disconnect the Bov if you have a pressure difference it could be the Bov opening early or a Bov not set up properly.
A small hose off or a hole not plugged might also give that pressure drop.
The BOV does open when at max vac.
It shouldn't affect the on boost behaviour though I wouldn't have thought.
Maybe I should try a stronger spring. Can't hurt...
1984 Sigma Super, Turbo Wagon
1990 GSR-VR 50,000ks
1984 GSR II 4G63 302kw atw at 24psi
