The newest 100% bolt on Greddy Hybrid turbocharger!
#252
Turbocharger Guru
Thread Starter
well if you have problems with the boost dropping off up top, just shorten that wastegate rod. It will give you more spring tension and the boost will go up. I have opened up that exhaust housing quite a bit to decrease back pressure and the turbine wheel is clipped for lower back pressure.
The boost fall off could be b/c the compressor wheel being too small. The engine was just using up all the air the turbo could flow and the boost would fall off.
Bryan
The boost fall off could be b/c the compressor wheel being too small. The engine was just using up all the air the turbo could flow and the boost would fall off.
Bryan
#260
Turbocharger Guru
Thread Starter
Well to start off, your turbine housing and turbine wheel dictate spool, backpressure and boost charactoristics. When you port the wastegate, that keeps boost creep under control. Porting the wastegate will make the boost drop off worse b/c there is more area for the backpressure to push on. When you get to maxing out the compressor side, that will cause that same drop off symptom. The compressor side being so small is what I think causes the drop off. Mitsubishi turbine housings are a open volute design which actually has a problem with creep.
#261
Boosted Kiwi
iTrader: (2)
Just looked up for a definition of boost creep and got this :
Boost creep: When the boost rises past the set limit. This is often caused by a wastegate that cannot handle the exhaust flow.
This does seem to happen at lower rpm with my setup . If you set for say 10 psi at 6000rpm I'll get maybe 12psi for 500rpm or so when I nail it at 4000 . Then later past 6500 it would drop to 7-8 psi . That is why I did a 2 stage controller setup - works great .
I now get 7-8 psi low down ramping up to 9-10 at 6500 then 10-11 from 6500 to the redline .
The car is way more controllable than it used to be ....
Boost creep: When the boost rises past the set limit. This is often caused by a wastegate that cannot handle the exhaust flow.
This does seem to happen at lower rpm with my setup . If you set for say 10 psi at 6000rpm I'll get maybe 12psi for 500rpm or so when I nail it at 4000 . Then later past 6500 it would drop to 7-8 psi . That is why I did a 2 stage controller setup - works great .
I now get 7-8 psi low down ramping up to 9-10 at 6500 then 10-11 from 6500 to the redline .
The car is way more controllable than it used to be ....
#262
Turbocharger Guru
Thread Starter
My 323 GTX has a mitsubishi TD06 turbo on it but with a 50 trim compressor. The minimum boost I can run is 18 psi. So I set the low side of the boost controller at 18 and get the full benifit of the improved mid range TQ of the upped boost.
#271
1st RX8 BNR Turbo Owner..
iTrader: (1)
Yes sorry guys, I have been busy not to mention very disappointed with the guy running the dyno session. He claimed that my tune from Kane was far to lean according to his new sniffer on the dyno. So he went ahead and made changes, resulting in making it rich as ****. So looks like I have to go elsewhere and have Kane unscrew the tune that the guy made me.
Who says that pushing the boost past 7-8 psi is to much. I am soo pissed that he wouldnt let me because he didnt want the engine to blow...GAY!!! So I wasnt able to go past it 7-8 psi. Then not to mention the tune was shitty. So this wouldnt even be accurate representation of what the turbo can do...
The fact that Kane's tune was making more power than his tune all the way up to when he let off the gas shows that Kane's was superior.
Than I do an AP dyno pull with the 2 different maps and got this info:
Dyno guy: 315 hp
Kane's tune: 352 hp
Tell me which is better?
Who says that pushing the boost past 7-8 psi is to much. I am soo pissed that he wouldnt let me because he didnt want the engine to blow...GAY!!! So I wasnt able to go past it 7-8 psi. Then not to mention the tune was shitty. So this wouldnt even be accurate representation of what the turbo can do...
The fact that Kane's tune was making more power than his tune all the way up to when he let off the gas shows that Kane's was superior.
Than I do an AP dyno pull with the 2 different maps and got this info:
Dyno guy: 315 hp
Kane's tune: 352 hp
Tell me which is better?
Last edited by J.Cab; 07-06-2009 at 05:00 PM.
#272
ap dyno is crap
did you actually get real data off the dyno?
what were your afr's in boost with kane's tune, and the dyno guy's tune?
did you actually get real data off the dyno?
what were your afr's in boost with kane's tune, and the dyno guy's tune?
Last edited by 05rex8; 07-06-2009 at 06:10 PM.
#273
1st RX8 BNR Turbo Owner..
iTrader: (1)
The AP dyno reads about right. Because it said 315hp and the dyno said 278. So with Kane's 352 it should put it right now around 290-300 on the dyno at 7-8 pounds.