BNR losing boost top end
alright, so i did a boost leak check. the BOV was leaking pretty good where it mounts (not the bov itself).
havent drove the car yet, i used some gasket maker and its holding now tho, once it cures in an hour ill go for a drive and see if it helps at all.
if not then ill try putting more preload on the wga
if that doesnt work, im getting an MBC
if THAT doesnt work.... well **** idk what to do after that. lol. but i think itl be better now.
havent drove the car yet, i used some gasket maker and its holding now tho, once it cures in an hour ill go for a drive and see if it helps at all.
if not then ill try putting more preload on the wga
if that doesnt work, im getting an MBC
if THAT doesnt work.... well **** idk what to do after that. lol. but i think itl be better now.
Well the main thing is the turbo is still small ( It should hold better then that).. The boost leak may be helping the falling out... the thing about the bnr is the wastegate itself is a lower pressure wastegate so the pid has to work hard to keep a good amount of boost. So a mbc is recommended... I had team ss tapering down to 22lbs from 24lbs back when i first tuned him because the 22 is the most i could get on the top end. And i told him he needs a mbc.. Now i have him tuned still running the mbc inline with the pid controller and it hold perfect..!!!!!!!! Even though i only have him at 24lbs, im sure if i went to say 28 he would prob taper down a lil!!!
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Right, but the turbine side is still the stock housing. While the bigger compressor will still make more power, it is limited by the small exhaust side.
An mbc would definitely make a much smoother boost curve but it would still fall off a little bit up top just due to backpressure.
Maybe I'm misinformed, but this has always been my understanding of turbos.
An mbc would definitely make a much smoother boost curve but it would still fall off a little bit up top just due to backpressure.
Maybe I'm misinformed, but this has always been my understanding of turbos.
How much preload should be put on the wga? Its a 15 psi spring and it only has like 1 1/2- 2 turns of preload.
This issue is so annoying because it pulls like a monster till 5200 rpm or so when I start losing boost to 20.
I also don't get full spool till like 3700 rpm or later.
This issue is so annoying because it pulls like a monster till 5200 rpm or so when I start losing boost to 20.
I also don't get full spool till like 3700 rpm or later.
Hmmm....yeah mine holds 25psi no prob. I made sure that the WG door was closed and then I gave it maybe two more turns. I know vince had to play with the WG table a bit to get it right since it was bleeding off too much at WOT. Mine holds 25psi to 7k.
My recirc tube for my bov is silicone so I just cut a small hole and tapped it in there. It was simple.
Not really. Im going to try tightening my wga rod down more tonight after work and see if it helps. Fixing the boost leak made gains on the butt dyno but the bleeding boost issue still exists.
fix the boost leaks. bring the car back to me.
the leak is a huge issue. if you need it welded, we can head down to mkc and get that done. any leak after the maf just narfed the tune.

p.s. we're not going to be sideways at 70 mph while airborne again either
the leak is a huge issue. if you need it welded, we can head down to mkc and get that done. any leak after the maf just narfed the tune.
p.s. we're not going to be sideways at 70 mph while airborne again either



