MKTurbo Sale Thread
#644
That is not true. I can speak from experience with this turbo. I was getting 10psi just of the WG pressure and the moment I turned up the boost It would creep that much further. Whats the point of get x psi if you don't reach x till the end of the power band? Why not just port it more so you can reach x earlier and hold it longer?
#645
Ya'll keep trying to act like creep is the same between each setup, but it can't possibly be the case. What might work for some, won't work at all for others. I hardly blended my wastegate port into the turbine housing, but I don't creep, just as an example.
Gate preload, tuning, boost plumbing, and daily conditions, etc... all likely play a larger part than you imagine in dealing with creep.
Ramping up boost past peak torque has been discussed other places on the forum. Long story short, if you aren't bending the rods at peak torque chances are you can keep running up the boost till the intake melts, you likely won't break rods and will just flatten the torque curve out into higher RPMs more.
Gate preload, tuning, boost plumbing, and daily conditions, etc... all likely play a larger part than you imagine in dealing with creep.
Ramping up boost past peak torque has been discussed other places on the forum. Long story short, if you aren't bending the rods at peak torque chances are you can keep running up the boost till the intake melts, you likely won't break rods and will just flatten the torque curve out into higher RPMs more.
#649
Elite Member
iTrader: (1)
Join Date: Apr 2014
Location: SF Bay Area, CA
Posts: 3,102
Total Cats: 559
OK I won't run MBC, maybe just have my friend add a 1/8" barb to reference when he adds my IAT bung post IC. That will just make it open a bit later but shouldn't change how it creeps once it's open right?
Maybe I will just set overboost to cut spark at 13psi and give it a go.
Here is a better 4th gear pull, starting to make 1psi at 1850rpm.
Maybe I will just set overboost to cut spark at 13psi and give it a go.
Here is a better 4th gear pull, starting to make 1psi at 1850rpm.
#650
Moderator
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 21,029
Total Cats: 3,123
That is not true. I can speak from experience with this turbo. I was getting 10psi just of the WG pressure and the moment I turned up the boost It would creep that much further. Whats the point of get x psi if you don't reach x till the end of the power band? Why not just port it more so you can reach x earlier and hold it longer?
#651
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,729
Total Cats: 4,126
IF 7000RPM = 12psi when the wastegate is fully open.
THEN it doesn't matter whatsoever what boost youre running in between so long as you get back to fully open by 7000RPM.
just like this:
wastegate vs ebc.
and again with more boost:
THEN it doesn't matter whatsoever what boost youre running in between so long as you get back to fully open by 7000RPM.
just like this:
wastegate vs ebc.
and again with more boost:
#652
I guess I'm not being clear enough. Without porting the curve will not be linear as it spools up then flat when the wg opens. It will overshoot and then flatten out. Example. Turbo spools up with ebc and will always overshoot until WG opens and then will settle at desired target. By porting you eliminate that overshoot and possible creep at certain psi. Granted if you pumped 20 psi through it that might not be the case.
#653
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,729
Total Cats: 4,126
what?
that above dyno is a non-ported wastegate.
learn how to turbo.
Notice how on all these logs, the wastegate rated point is clear. You can see mine was a 7psi actuator if you look at the knee point on the boost log.
The turbo spools normally in a exponential fashion, boost forces the actuator to open the wastegate, but it's not enough to divert enough exhaust away from the turbine. So as your increase rpms, the boost also increases in a linear fashion because the exhaust forces are increasing with rpm, but you can only divert so much past through the wastegate around the turbine.
creep and porting have nothing to do with your spool-up characteristics--that's happening when the wastegate is CLOSED.
that above dyno is a non-ported wastegate.
learn how to turbo.
Notice how on all these logs, the wastegate rated point is clear. You can see mine was a 7psi actuator if you look at the knee point on the boost log.
The turbo spools normally in a exponential fashion, boost forces the actuator to open the wastegate, but it's not enough to divert enough exhaust away from the turbine. So as your increase rpms, the boost also increases in a linear fashion because the exhaust forces are increasing with rpm, but you can only divert so much past through the wastegate around the turbine.
creep and porting have nothing to do with your spool-up characteristics--that's happening when the wastegate is CLOSED.
#654
Moderator
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 21,029
Total Cats: 3,123
My EBC doesn't ever overshoot. It has a setting called "gain" that regulates how early and quickly it opens to prevent overshoot. It's the Greddy Profec B.
Please try an experiment for me prior to more porting. Disconnect the wastegate actuator from the flapper arm and see what boost you get at redline. If it truly needs porting it will be in significant boost when the wastegate is wide open (8psi+). Otherwise it just needs a weaker actuator to allow it to open more readily when you reach the target.
Please try an experiment for me prior to more porting. Disconnect the wastegate actuator from the flapper arm and see what boost you get at redline. If it truly needs porting it will be in significant boost when the wastegate is wide open (8psi+). Otherwise it just needs a weaker actuator to allow it to open more readily when you reach the target.
#655
what?
that above dyno is a non-ported wastegate.
learn how to turbo.
Notice how on all these logs, the wastegate rated point is clear. You can see mine was a 7psi actuator if you look at the knee point on the boost log.
The turbo spools normally in a exponential fashion, boost forces the actuator to open the wastegate, but it's not enough to divert enough exhaust away from the turbine. So as your increase rpms, the boost also increases in a linear fashion because the exhaust forces are increasing with rpm, but you can only divert so much past through the wastegate around the turbine.
creep and porting have nothing to do with your spool-up characteristics--that's happening when the wastegate is CLOSED.
that above dyno is a non-ported wastegate.
learn how to turbo.
Notice how on all these logs, the wastegate rated point is clear. You can see mine was a 7psi actuator if you look at the knee point on the boost log.
The turbo spools normally in a exponential fashion, boost forces the actuator to open the wastegate, but it's not enough to divert enough exhaust away from the turbine. So as your increase rpms, the boost also increases in a linear fashion because the exhaust forces are increasing with rpm, but you can only divert so much past through the wastegate around the turbine.
creep and porting have nothing to do with your spool-up characteristics--that's happening when the wastegate is CLOSED.
You are right creep and porting do not have anything to do with spool up but the WGA does.
Again what I am talking about is the early onset of boost in which you overshoot the target and then taper down. EVEN your second dyno shows this. You overshoot down in the lower rpm then taper down. Where as just off of WGA by itself you slowly increase pressure.