no power when turbo is on a real heavy load....?
09-12-2012, 06:44 AM
#22
If air fuel reads 12.5 when it does this, it is reading lean when it happens...my guess is this is fuel not getting burnt in the cylinder...misfire/spark blow out. Tuned on a couple cars that had this issue. Both times it ended up being coil pack related and both times it would happen under heavy load only.
09-12-2012, 09:16 AM
#23
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[QUOTE=Sarg;16713587]If air fuel reads 12.5 when it does this, it is reading lean when it happens...my guess is this is fuel not getting burnt in the cylinder...misfire/spark blow out. Tuned on a couple cars that had this issue. Both times it ended up being coil pack related and both times it would happen under heavy load only.[/QU
I am the tuner. It actually goes rich from 11.5 to around 10.5 when it happens. But when it does not do it not high load situations or lower boost it stays 11.5. I think its either going to be spark blowout or floating valves from not enough seat pressure.
I am the tuner. It actually goes rich from 11.5 to around 10.5 when it happens. But when it does not do it not high load situations or lower boost it stays 11.5. I think its either going to be spark blowout or floating valves from not enough seat pressure.
09-12-2012, 10:49 AM
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Try a NGK R5724-10 7993 spark plug, It comes gapped about .016-.018 out of the box. I had to use them on mine as I was blowing the spark out at 12+lbs.
I wouldn't think they valvesprings would be the issue being recently replaced, but they could be too weak. If you want to rule out converters, my car will be apart sometime this weekend and you can try the th400/nelson billet converter. Are you running tractor fluid yet? Brass mesh filter or paper?
Have you looked at a compressor map for your turbo?
I wouldn't think they valvesprings would be the issue being recently replaced, but they could be too weak. If you want to rule out converters, my car will be apart sometime this weekend and you can try the th400/nelson billet converter. Are you running tractor fluid yet? Brass mesh filter or paper?
Have you looked at a compressor map for your turbo?
09-12-2012, 11:06 AM
#28
You realize it doest matter right? Heat spools the turbo. Fact. The more heat you put into it the faster it will spool....that is not to say the car will feel faster since you are actually loosing heat out of the exhaust that would otherwise be consumed in the power stroke, but the turbo will most definitely spool faster. Which is why you want to take out timing to spool, then put it back in once you get into boost.
Lean and advance the timing until you get 5-8psi built then you can retard the timing to move the combustion event out of the chamber/cylinder and into the manifolds where the heat in them lights off the mixture closer to the turbine adding more boost to what you've already made from advancing the timing and keeping it lean(12.3-13.0).
I have also found this to be the best way to do it it with the best results.
Stangkillr check your boost controller settings to see if it's causing the spike, it sounds like it is blowing out spark to me. If it was blowing out the spark opening the gap up to .25 isn't going to help take it down to .17-.18 and see if it helps. Talk to Nitroused383 he had this same problem for a long time and he chased his *** with coils, plugs, plug wires and finally got a set of Firecore plug wires and it really helped along with a different set of coils.
IIRC you're running a LS9 cam why not shim the springs to get more seat pressure out of them or is this your next move?
09-12-2012, 11:30 AM
#29
You have to advance the timing first and actually get the turbo shaft speed up and get some *** in the thing before you yank the timing out from under it.
Lean and advance the timing until you get 5-8psi built then you can retard the timing to move the combustion event out of the chamber/cylinder and into the manifolds where the heat in them lights off the mixture closer to the turbine adding more boost to what you've already made from advancing the timing and keeping it lean(12.3-13.0).
I have also found this to be the best way to do it it with the best results.
Lean and advance the timing until you get 5-8psi built then you can retard the timing to move the combustion event out of the chamber/cylinder and into the manifolds where the heat in them lights off the mixture closer to the turbine adding more boost to what you've already made from advancing the timing and keeping it lean(12.3-13.0).
I have also found this to be the best way to do it it with the best results.
09-12-2012, 11:45 AM
#30
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Quick couple of questions atomic - how many LS turbo cars have you tuned? How many were street cars, and how many were track only? How fast did they go? How much power did they make?
This thread is not about how to spool a large frame turbo automatic on the street. Its about a power loss issue. If you want to argue about what spools what faster on the internet go check out the other spooling threads.
This thread is not about how to spool a large frame turbo automatic on the street. Its about a power loss issue. If you want to argue about what spools what faster on the internet go check out the other spooling threads.
09-12-2012, 11:58 AM
#31
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In order to achieve your theory, atomic, you would need to pull an insane amount of timing out like in antilag maps (but that is still based on pressure over the amount of heat it produces). Retarding the timing only achieves one positive goal: increasing exhaust temp, but conversely reduces cylinder pressure and engine power/output
Advancing the timing achieves two positive goals: increasing exhaust gas velocity and volume as well as increasing engine power...
Sorry op for off topic banter. Check coils, checl voltage @ coils, reduce gap, check grounds
Advancing the timing achieves two positive goals: increasing exhaust gas velocity and volume as well as increasing engine power...
Sorry op for off topic banter. Check coils, checl voltage @ coils, reduce gap, check grounds
09-12-2012, 11:59 AM
#32
Quick couple of questions atomic - how many LS turbo cars have you tuned? How many were street cars, and how many were track only? How fast did they go? How much power did they make?
This thread is not about how to spool a large frame turbo automatic on the street. Its about a power loss issue. If you want to argue about what spools what faster on the internet go check out the other spooling threads.
This thread is not about how to spool a large frame turbo automatic on the street. Its about a power loss issue. If you want to argue about what spools what faster on the internet go check out the other spooling threads.
My point is not to jack the guys thread, so I will keep to myself after this, but putting out information on how to tune turbos should not be frowned upon whevere it is. Is it answering his issue directly? No, but it is relavent to his setup so he (or anyone else that reads this thread) may find it useful. I would not say this is an argument, but rather a discussion. Maybe we are splitting hairs when it comes to practical differences in performance, but the theory is sound. But anyway, I digress.
To the OP, I appolgize for clogging your thread, but the discussion seemed to be something you might be interested in. I agree on changing out the plugs and/or trying a tighter gap.
09-12-2012, 12:20 PM
#33
Quick couple of questions atomic - how many LS turbo cars have you tuned? How many were street cars, and how many were track only? How fast did they go? How much power did they make?
This thread is not about how to spool a large frame turbo automatic on the street. Its about a power loss issue. If you want to argue about what spools what faster on the internet go check out the other spooling threads.
This thread is not about how to spool a large frame turbo automatic on the street. Its about a power loss issue. If you want to argue about what spools what faster on the internet go check out the other spooling threads.
i'm confident kc will be bringin some whoop ***
09-15-2012, 12:52 PM
#37
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Thanks! I have really been trying to get the car to work from a 1st gear roll and digs. I am about to go try some stuff out on the car mentioned in this thread right now. Its been a busy last week for me.