MONTE CARLO "COPO" Monte Carlo SS - Turbosaurus Build (Swinging Dick Racing's c*ck got bent... she bounced a little too high & hard, & came down awkwardly)
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I'd agree if this were my main/only focus. A decent result is good enough for this season.
I just plugged the new tune in it... after explaining to Tatiana the principles of tuning right before bed. Her request, not mine. She then asked me to load HPTuners on her computer so she could play with the VE tables 3D graphics.
She's hooked now - muhahahahaha!
Ever had one of those "oh sh*t!" moments? Well tonight was one of them. It wasn't necessarily a bad thing just a lot happening very fast.
As you can see below the car is making more boost... and we can assume more power. The white vertical line shows the point where the second stage (the big one) comes on. Moments later you can see how the EQ ratio falls way off. This was already after a bit of tuning (its been gone through again). I adjusted the boost controller to slow down the ramp rate as the car was near impossible to drive. I can put it back to a more aggressive setting at the track (WG%, gain, and start pressure (currently 10, could go back to 5 - or lower and risk a boost spike).
The whole OS is now at its peak/limit (210kpa) and the boost controller is hitting boost cut and is smashing against a 16psi celling (as set by me). The obvious thing to do is go to a 3 bar OS.
The general consensus is that this turbo is incapable of going above 11psi at full song (at least if you believe everything Holdner tells you):
www.motortrend.com
I am guilty of believing this for a long time, at least until I took a step back and recognized that nothing he was doing to control boost would facilitate the turbo going over a self-imposed limitation. So with proper boost control and equipment it would seem that exceeding the commonly accepted numbers is possible.
If you look far enough back there is evidence that these GT45 turbos have a lot of potential over and above what we've been told.
Run at 13.5 and 15psi respectively:
Upwards of 26psi:
And a more legitmate 9 second pass at 17+psi:
So long as the air flow (g/s) keeps going up it clearly is still working well enough, obviously still battling high (but, steady) IATs.
As you can see below the car is making more boost... and we can assume more power. The white vertical line shows the point where the second stage (the big one) comes on. Moments later you can see how the EQ ratio falls way off. This was already after a bit of tuning (its been gone through again). I adjusted the boost controller to slow down the ramp rate as the car was near impossible to drive. I can put it back to a more aggressive setting at the track (WG%, gain, and start pressure (currently 10, could go back to 5 - or lower and risk a boost spike).
The whole OS is now at its peak/limit (210kpa) and the boost controller is hitting boost cut and is smashing against a 16psi celling (as set by me). The obvious thing to do is go to a 3 bar OS.
The general consensus is that this turbo is incapable of going above 11psi at full song (at least if you believe everything Holdner tells you):
How To Make 800 hp With a $163 eBay Turbo.
We test the hype and dispel the myths about inexpensive off-shore turbos that stretch credibility with huge claims of performance for the money.
www.motortrend.com
I am guilty of believing this for a long time, at least until I took a step back and recognized that nothing he was doing to control boost would facilitate the turbo going over a self-imposed limitation. So with proper boost control and equipment it would seem that exceeding the commonly accepted numbers is possible.
If you look far enough back there is evidence that these GT45 turbos have a lot of potential over and above what we've been told.
Run at 13.5 and 15psi respectively:
Gt45 turbo how much power can it make? - LS1TECH - Camaro and Firebird Forum Discussion
Forced Induction - Gt45 turbo how much power can it make? - Anybody running one of these? On a 5.3 just seeing what kind of hp it can make
ls1tech.com
Upwards of 26psi:
Max boost? GT45, stock LM7, 93/ no meth - LS1TECH - Camaro and Firebird Forum Discussion
Forced Induction - Max boost? GT45, stock LM7, 93/ no meth - 100% unopened LM7. Currently have it up to 8.5psi on 93 pump gas. What is the highest you've run with this combo on straight pump gas? http://img.photobucket.com/albums/v699/jonvolk/Mobile%20Uploads/image_zps2bcbc6f7.jpg
ls1tech.com
And a more legitmate 9 second pass at 17+psi:
eBay gt45, stock 4.8, goes 9.18@146 - LS1TECH - Camaro and Firebird Forum Discussion
Forced Induction - eBay gt45, stock 4.8, goes 9.18@146 - Hey guys figured I would post a thread with updates. We have one last chance to get the car out this weekend. The above was at 17.5 psi due to boost controller issues that we believe we have figured out. The above was also on a 3.91 gear...
ls1tech.com
So long as the air flow (g/s) keeps going up it clearly is still working well enough, obviously still battling high (but, steady) IATs.
The turbo can only supply as much air it’s compressor is capable of. It won’t go above that reliably for long.
You’ll know when you hit the limit because the IAT’s will climb rapidly, basically it makes heat, boost and not anymore power.
Not disagreeing with you, but rather pointing out ‘the proof is in the pudding’ haha.
You’ll know when you hit the limit because the IAT’s will climb rapidly, basically it makes heat, boost and not anymore power.
Not disagreeing with you, but rather pointing out ‘the proof is in the pudding’ haha.
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Paint the compressor housing, when the paint burns, you went to high. Adjust as required.
That's the thing. The prejudice against these turbos is that they just don't perform over a set "boost" level. As I have always maintained: boost is just a measure of restriction - the only thing that matters is mass air flow (as influenced by other factors). The turbo's job is to move air (ideally as efficiently as possible), it just does so with battling pressure. People who talk about boost without looking at the other factors are: F*CKING IDIOTS.
"Durr, durr, how much boost?!"
The reason that I spent so much time porting things was to modify the factors which contribute to the limitations of "boost" or the out of the box nature of the GT45. Holdner, despite being prompted, has NEVER measured the IATs or air flow of any turbo he's tested. He simply, as any simpleton and reductionist would, only looks at boost and AFR (and occasionally back pressure) because that is all he and his core audience understands (or chooses/has the capacity to endure). It's easy consumption nonsense.
Getting back to the data above, the IATs start at 120*F and end at 127*F before I lifted. That is a 7*F change in 2.8 seconds. So clearly it isn't super-heating the air charge (chemical intercooling notwithstanding), and sensor latency isn't an issue either as the IATs stabilized at 133*F after the pull. Additionally, the Dynamic Airflow is still rising despite the boost plateauing (assuming it hadn't over shot 16psi/210kpa and wasn't going to the moon (I cannot safely stare a gauge and the road).
Obviously, I am now limited by data (as it relates to pressure), although I could run the crappy Innovate LogWorks program to get a figure. So I guess I need to open my wallet and recapture that important but, limited capability in HPTuners. But, so long as it has enough fuel and is not knocking we should be good to go for the time being.
The other thing that has me wondering what I am at the limit of now are my valve springs.
Last thing since my work computer just finished updating...
This is the effect that running uncalculated (non-ECM controlled) fueling (methanol injection) has on a VE table in an Open Loop OS:
If I had a Closed Loop correction it wouldn't matter, it would self adjust and the VE would be normal. It is what it is, until the meth pumps fail and the engine goes boom because it has no safeties integrated other than the boost controller having a AFR-based boost cut.
Truer words never spoken
All pressure is a measure of restriction. Oil, fuel, etc.
If you were at 11 before, why not just run it 15-16 for now, tune for it, and see if the car gets down the 1/4 mile before going 3 bar and full send? You have more than enough injector for it. If you go SD, you can work around the MAF limit. Or rescale the whole thing and keep the MAF. Or break down and get a Holley Terminator.
To clarify we are already SD. But, otherwise, yes - you are correct and that's my plan. But, a 3 Bar MAP is just $31 and the OS change is free... so... ya know... why not?
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