Guest Anonymous Posted July 9, 2001 Share Posted July 9, 2001 Ok gang, i have a 75 280z that i have installed a aftermarket bolt on turbo too. Everything is installed, all the piping run, the oil lines are connected, everything is go.. but i am getting no boost. NONE, not even at 3000 rpm. the turbo is hot, which i guess is to be expected, but it is running just like it used to in N/A mode. my boost gauge is showing 20lb of VACUUM at idle and when i rev it goes to 10lb VACUUM. so i took off the intake pipe to the turbo to see if the turbine was spinning, keep in mind since the AFM is no longer hooked up it can not come off of an idle, but when i start it, that initial puff of exhaust makes the turbine spin, but then the turbine quickly spins down and stops.. The turbo was recently rebuilt and i am not getting a leak between the manifold and the turbo, i have good exhaust pressure out of the tail pipe.. what am i missing.. how freely should the turbine spin? it is not extremely loose, but smooth turning. Is anyone out there that can help?? Thanks guys! Joe75z Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 9, 2001 Share Posted July 9, 2001 Not exactly a "turbo god", but assuming the turbo is good and not seized, check your wastegate to ensure it is closed and not bypassing the turbine. And I only saw a guy do this once on a homemade installation, but you didn't by any chance hook the exhaust side of the turbo up backwards? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 9, 2001 Share Posted July 9, 2001 nah it is hooked up right, and there is no wastegate on this turbo, just uses a blowoff valve. I took it for a drive and under a full load with 100% open throttle my boost gauge shows "0".. any more ideas? Quote Link to comment Share on other sites More sharing options...
Drax240z Posted July 9, 2001 Share Posted July 9, 2001 quote: Originally posted by Joe75z: nah it is hooked up right, and there is no wastegate on this turbo, just uses a blowoff valve. You mean pop-off valve? If you are expecting a blow off valve to control your boost levels, you've got problems. No wastegate? Not internal nor external? I'd be afraid to run without one. Why don't you have a wastegate? If its not a wastegate problem then I would wonder if you were getting oil pressure to the bearings in the turbo or not. Or if it was incorrectly rebuilt. Quote Link to comment Share on other sites More sharing options...
TimZ Posted July 9, 2001 Share Posted July 9, 2001 quote: Originally posted by Drax240z: You mean pop-off valve? If you are expecting a blow off valve to control your boost levels, you've got problems. I was just going to say the same thing. The popoff is a SAFETY BACKUP ONLY, and not a very good one, at that. It's probably a good thing that you aren't getting any boost. What turbo do you have? Is it a T3 or T3/T4? I'm wondering if the wastegate port is just wide open, and you are dumping all the exhaust gas out of it. My ONLY advise at this time is to get a wastegate on there! [ July 08, 2001: Message edited by: TimZ ] Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 9, 2001 Share Posted July 9, 2001 ok, the BAE turbo kit, which is what it is, was made WITHOUT a wastegate. This is one of the aftermarket systems built for the early Z's. The boost was controled by a popoff/blowoff (i know there is a difference). but regardless i am still not getting any boost. Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted July 9, 2001 Share Posted July 9, 2001 Ahh the BAE. My buddy over here has the bae kit. Kinda cool. The turbo usually wont spin at idle. Now my question is, can you hear anything coming out of the blowoff/popoff valve? This is very hard to diagnose because its such a simple system. Simple system must equal simple fix right? lol.. I dont know what your problem is, but if you need me too i can look at my buddies car. Evan Quote Link to comment Share on other sites More sharing options...
Drax240z Posted July 9, 2001 Share Posted July 9, 2001 Huh, well I learned something. Gotta love it when that happens. OK, so no wastegate. One question... Do you feel lucky pu... oops, wrong question. Are you just trying to make boost sitting still and free revving the engine, or are you getting no boost under load as well? (ie: driving) Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 9, 2001 Share Posted July 9, 2001 ok yeah i am getting NO BOOST under a full load, and when my throttle is fully open my boost gauge shows 0. I really cant hear anything coming out of the popoff valve nor can i feel anything.. mostly because of the air coming off of the fan. I know the turbine initially spins, but i just can tell what it is doing when i am driving.. Thanks guys we are getting somewhere!! Quote Link to comment Share on other sites More sharing options...
TimZ Posted July 9, 2001 Share Posted July 9, 2001 Are you using the turbo that came with the BAE setup, or is it a different one? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 10, 2001 Share Posted July 10, 2001 same one, but i am not using the adapter tube that came with it that bolts up to the factory manifold and turbo, i am using a stock 280zx turbo manifold. Quote Link to comment Share on other sites More sharing options...
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