GMTECH12002
Member
- Joined
- Dec 1, 2004
- Messages
- 143
i am working on a friends 85 gn ha. i put a new long block and a new ta44 from gbody.com heres my issue, the turbo seems like its either too hard to turn or there could be a major boost leak. Heres what i mean by that, the engine is very slugish on takeoff and even through the rpm range, and the turbo will only make around 14 or 15 psi no matter what i do to the wastegate. i completely bypass the w/g solenoid and just use a manual bleeder and can just barely get to 14 psi. I suspected maybe a leak around the cast inlet pipe from the turbo to the intake, but i sprayed with soapy water and brakes torqued to around 8 psi and no bubbles, so then i thought maybe the wastegate puck inside the exhaust housing was not sealing, i took the turbo off again and took off the exhaust housing to find it seems to have a good seal at the puck when closed, but should there be a gasket at the exhaust housing to the center cartridge, also i spun the inlet wheel by hand and it seems to have alot of drag on it, it stopped spinning as soon as i quit turning it by hand, how much free spin should i expect from a new turbo. also i believe this engine/turbo combo has about a thousand miles on it since i installed it and the turbo has notable endplay, infact i dont have a dial indicator but i would say it has more endplay than my 87 stock turbo with 60k miles on it. i would really appreciate some tips and opinions of where to go from here with this, cause i am not at all familiar with HA cars but i would assume a healthy powertrain with an upgraded turbo and 30 lbs injectors, an open cone air filter, staight pipe exhaust no converter and a jays gn chip would produce some nice gains in hp. i would also expect this turbo to spike up into the 20-25 psi range when the wastegate is tied shut. with some serious detonation, but i cant get more than 14 or 15 psi out of it, is any of this realistic?