Highest Horsepower dynos for SC Turbo and nitrous - post them here
08-30-2009, 08:38 PM
#179
ok here is mine as promised...had a boost spike that we couldn't tune out with the bc....*sigh*
BC was set to about 10psi. This is Fluid Motorsports "upgraded" GReddy turbo...
BC was set to about 10psi. This is Fluid Motorsports "upgraded" GReddy turbo...
Last edited by 05rex8; 08-30-2009 at 09:00 PM.
08-30-2009, 09:44 PM
#180
Life begins @ 30 psi
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Cool 05rex8, nice torque... once you get the boost spike sorted are you going to re-dyno? How is the Fluid turbo modified from the regular TD06? The boost looks like it drops off pretty dramatically in the upper ranges like the TD06.
08-30-2009, 09:56 PM
#181
Therefore, it's the turbo and/or wastegate actuator; most likely the latter. No tuning of the bc will make it go away really.
Last edited by 05rex8; 09-07-2009 at 03:42 PM.
08-30-2009, 10:00 PM
#182
read this:
https://www.rx8club.com/series-i-major-horsepower-upgrades-93/cheap-two-stage-boost-controller-greddy-turbos-177007/
and the boost control and wastegate section of this :
https://www.rx8club.com/series-i-major-horsepower-upgrades-93/getting-most-out-your-greddy-turbo-without-breaking-bank-172542/
08-30-2009, 10:05 PM
#184
yeah I have seen those
I already tightened the w/g actuator arm, which did not do much for me
I suppose I should try a bigger actuator before I conclude that the turbo is the problem
I already tightened the w/g actuator arm, which did not do much for me
I suppose I should try a bigger actuator before I conclude that the turbo is the problem
08-30-2009, 10:07 PM
#185
i can include a new chart with afr's if you want
we had to run it pig rich to compensate for a lean condition from the spike...it's not a pretty looking graph lol
08-30-2009, 10:09 PM
#186
/\ you need to take the lock nut right off , shorten the actuator arm by 3mm (i used a disc grinder to do this) then screw the arm in as far as possible .Trust me - you will not be disappointed with the results . That turbo you have there will do 300whp easily .
08-30-2009, 10:11 PM
#187
crap I didn't know about shortening it 3mm. I must have missed that part. I will try it.
08-30-2009, 11:00 PM
#193
It is actually perfect for racing from a roll in 2nd gear - someone told me ...
Because you typically mash it at around 4500-5000 and if you are making too much torque in that range you just light up the tyres and the traction control starts modulating the throttle . With progressive boost you can mash it and know your tyres are right on the limit and you get maximum acceleration.
I have changed my boost control setup (again) after seeing Chickens dyno so I can switch on the boost controller and get 12-13psi boost all the way and get a dyno similar to his . But for most situations I really like the progressive boost i have now .
Because you typically mash it at around 4500-5000 and if you are making too much torque in that range you just light up the tyres and the traction control starts modulating the throttle . With progressive boost you can mash it and know your tyres are right on the limit and you get maximum acceleration.
I have changed my boost control setup (again) after seeing Chickens dyno so I can switch on the boost controller and get 12-13psi boost all the way and get a dyno similar to his . But for most situations I really like the progressive boost i have now .
Last edited by Brettus; 08-30-2009 at 11:04 PM.
08-31-2009, 02:51 PM
#194
Everything is good up until 4000rpm at which point your "higher flowing" wastegate is pushed open by the pressure inside the turbo because the actuator spring was only built for 5psi and the extra area opened up by the porting means a greater force acting on the wastegate than stock .
Now because you effectively have a pre turbine exhaust leak AND your turbine is clipped , you are making pitiful power all the way up till 6500 . This is when the aux port opens and there is a suddend rush of air into the motor . This rush of air spools up the turbo to an extent but the wastegate is still being pushed open despite yopur atempt to control it via the boost controller .
So what do you do ? You need to get as much of the exhaust gasses as possible flowing through the turbine .
A bigger actuator would help a lot but i think you can control it using the stock actuator if you are prepared to muck around a bit .
Shortening the arm is the first step - so i'm interested to hear what effect that has ....
08-31-2009, 03:03 PM
#195
Original Turbo 'd Auto !!
I think I know what happened in your run ...
Everything is good up until 4000rpm at which point your "higher flowing" wastegate is pushed open by the pressure inside the turbo because the actuator spring was only built for 5psi and the extra area opened up by the porting means a greater force acting on the wastegate than stock .
Now because you effectively have a pre turbine exhaust leak AND your turbine is clipped , you are making pitiful power all the way up till 6500 . This is when the aux port opens and there is a suddend rush of air into the motor . This rush of air spools up the turbo to an extent but the wastegate is still being pushed open despite yopur atempt to control it via the boost controller .
So what do you do ? You need to get as much of the exhaust gasses as possible flowing through the turbine .
A bigger actuator would help a lot but i think you can control it using the stock actuator if you are prepared to muck around a bit .
Shortening the arm is the first step - so i'm interested to hear what effect that has ....
Everything is good up until 4000rpm at which point your "higher flowing" wastegate is pushed open by the pressure inside the turbo because the actuator spring was only built for 5psi and the extra area opened up by the porting means a greater force acting on the wastegate than stock .
Now because you effectively have a pre turbine exhaust leak AND your turbine is clipped , you are making pitiful power all the way up till 6500 . This is when the aux port opens and there is a suddend rush of air into the motor . This rush of air spools up the turbo to an extent but the wastegate is still being pushed open despite yopur atempt to control it via the boost controller .
So what do you do ? You need to get as much of the exhaust gasses as possible flowing through the turbine .
A bigger actuator would help a lot but i think you can control it using the stock actuator if you are prepared to muck around a bit .
Shortening the arm is the first step - so i'm interested to hear what effect that has ....
i ran across this very thing after porting the wg port and the manifold. So it was either replace the wg with one that larger diaphram, or shorten the actuator arm.. The arm mod was quicker and easier.
It did take some fiddleing around with too get right though.
08-31-2009, 03:41 PM
#196
I don't really understand why Fluid and BNR insist on porting the wastegate in combination with clipping the turbine . It is counter to what we want i believe .
With the upgraded compressor wheel the turbine wheel now becomes the weak link . IE the turbine housing/wheel combination is too small to power up the compressor .
This means more backpressure is created as the engine is constricted by the small turbine . Porting the wastegate just makes it harder for the already undersized actuator to control boost .
Clipping the turbine exacerbates this effect because when the turbine is clipped you want pretty much all of the flow to go through the turbine and you dont get that if the wastgate is being forced open .
Shortening the arm actually closes off the wastegate significantly and on my turbo induces boost creep . Something which I have found very desireable for getting the most from the turbo without it creating drivability issues.
With the upgraded compressor wheel the turbine wheel now becomes the weak link . IE the turbine housing/wheel combination is too small to power up the compressor .
This means more backpressure is created as the engine is constricted by the small turbine . Porting the wastegate just makes it harder for the already undersized actuator to control boost .
Clipping the turbine exacerbates this effect because when the turbine is clipped you want pretty much all of the flow to go through the turbine and you dont get that if the wastgate is being forced open .
Shortening the arm actually closes off the wastegate significantly and on my turbo induces boost creep . Something which I have found very desireable for getting the most from the turbo without it creating drivability issues.
08-31-2009, 03:47 PM
#198
The turbine on the GReddy turbo has a fairly substantial AR, so increasing the WG bypass probably isn't necessary.
However, even on a totally original GReddy turbo, the provided actuator is incorrectly sized for any output above 6 PSI.
The actuator diaphragm diameter should be increased by the same ratio that the boost is upped.
However, even on a totally original GReddy turbo, the provided actuator is incorrectly sized for any output above 6 PSI.
The actuator diaphragm diameter should be increased by the same ratio that the boost is upped.
08-31-2009, 04:53 PM
#199
This is because the exhaust pressure on the wastegate is applying a higher % of the force required to open it than on other applications .
So a small (stock) diaphram in combination with a bigger spring is what we need for decent control of boost - only if we want to max. out the turbo that is .
Last edited by Brettus; 08-31-2009 at 04:55 PM.
08-31-2009, 05:15 PM
#200
Nope.
That is to say, you could try to fix it that way, but you would not have the linear control you would have simply controlling the ratio of wastegate area to actuator area.
I already spent a considerable amount of time on this 3 years ago and wrote about it extensively.
If you want to reinvent the wheel (again), that's up to you.
That is to say, you could try to fix it that way, but you would not have the linear control you would have simply controlling the ratio of wastegate area to actuator area.
I already spent a considerable amount of time on this 3 years ago and wrote about it extensively.
If you want to reinvent the wheel (again), that's up to you.