hey, i finished my turbo kit yesterday and today i tried to fire it up. It starts perfectly, and idles fabolously. I'm using an internally wastegated t3. I finally rigged up my wastegate so it fits and works properly (it's just a temporary solution since i go to college within the week and i just wanted to feel how my boosted project came out).

I hooked up everything and took it for a spin, but i'm getting no boost. Checked for leaks, didn't find any in the charge pipes. Checked the blow off valve to see if it's releasing air, and it is. Watched the flapper while revving the engine and it opens and closes fine. But still no boost. I finally hooked up a boost gauge that someone let me borrow to make sure i'm building boost. I unhooked my BOV for a second and hooked up the boost gauge. It reads about 15 on the vacuum side. Would that mean there is a vacuum leak? I'm thinking it's a possible weak vacuum because i'm using the same tube for my FMU too (ik FMU's suck, but that's not the point here, unless you do think it's the problem but i can't see how it is.) Should i move the BOV to another vacuum location? Would that help at all? I've been looking at this car for such a long time i think it'll be helpfull to hear some other opinions. Thanks for any help on this topic. Quick replys always encouraged

 

If you have your FMU bov and boostgauge and WG signal line, it can affect your readings on your gauge and signals to whatever else its hooked to. Hook your FMU and WG line to their own line and run the boost gauge and bov to thier own line. Also make sure that you dont have your WG flapper fully open so that your bleeding off all the exh. that will make your turbo spool... Also, if you dont have some sort of a downpipe, your turbo wont spool, well mine didnt. It would only build like 4psi at like 7k.... Then i put a 2ft DP on it and I hit full boost... It was nutts... Good luck!

Blaze

 

thanks for the reply..i have a full 2.5in. exhaust so that's not a problem. I have now since tried a few different combos. First off, the wastegate vacuum is just hooked up to a nipple coming off the turbo. I moved the BOV vacuum to a it's own vacuum line now, now only the FMU is using the vacuum off the FPR. So it seems that each unit has it's own vacuum, but there still seems to be a leak somewhere. I guess i'll just have to go back and double and triple check every hose i've touched to make sure nothing has come undone or loosened up. Anyother advice would be grealy appreciated.

 

Ive noticed that SOHCs tend to have a lil bit lower vaccum once they are boosted, I dont know why this occurs but Ive seen it personally on 2 different SOHC boosted motors. One was VTEC and the other was not. One idled @ 12 in vac. and the other is @ 16 in vac. The one that idled at 12 had a T25 and the one that was @ 16 has a 14b. I know that before the one with the 14b idled at 18-19, we checked and triple checked and for leaks and never did find any....

Have you tried hitting boost yet?

 

did your friends SOHC boosted projects hit boost even though they idled in a low vacuum like that?