what the hell is causing this restriction with my tune???
Originally Posted by kenp
I don't see ant COT, but I do see Catalytic Convertor Protection Enable/Disable under Cat Convertor in EFIlive. Is that what's being referred to?
wow! thanks for all the replies guys.
yes you guys are correct, the motor goes RICH after about 5000 and my tuner, Steve who used to tune for GMR is telling me he doesnt know why it is going rich. He says he has pretty much NO fuel being added up top.
He is telling me that the MAF is not the problem. However I do have 4 sponsors on this site saying that the MAF could be the problem if the tables arent set correctly.
Steve emailed the tune to Louis at LG motorsports and he was suppost to take a look at it but I havent heard anything from him in 2 weeks.
The injectors are the 28.8lbs which the motor was tuned 100% with them before. If Im out of injector, I thought I would be lean...not rich.
Catalytic Convertor Protection Enable/Disable??? not sure what this is but I dont have CATS at all. Im going to email this thread to Steve and see what he thinks. Any more ideas let me know.
Thanks everybody.
yes you guys are correct, the motor goes RICH after about 5000 and my tuner, Steve who used to tune for GMR is telling me he doesnt know why it is going rich. He says he has pretty much NO fuel being added up top.
He is telling me that the MAF is not the problem. However I do have 4 sponsors on this site saying that the MAF could be the problem if the tables arent set correctly.
Steve emailed the tune to Louis at LG motorsports and he was suppost to take a look at it but I havent heard anything from him in 2 weeks.
The injectors are the 28.8lbs which the motor was tuned 100% with them before. If Im out of injector, I thought I would be lean...not rich.
Catalytic Convertor Protection Enable/Disable??? not sure what this is but I dont have CATS at all. Im going to email this thread to Steve and see what he thinks. Any more ideas let me know.
Thanks everybody.
Last edited by 30th t/a; Jul 3, 2007 at 08:30 PM.
Originally Posted by 30th t/a
the motor goes LEAN after about 5000
Originally Posted by 30th t/a
If Im out of injector, I thought I would be lean, not rich.
Originally Posted by Rhino
or
I'm confused. I would expect you to say that you're running rich, but you state it's running lean?
I'm confused. I would expect you to say that you're running rich, but you state it's running lean?
sorry, I meant rich. thanks for catching that.
at 4900 im at 12.9 a/f, at 6500 im at 12.3 a/f and at 6900 im at 11.7 a/f
What we are looking at is if you have enough pump to move the volume of fuel needed and the injector's are too small they are going past 100% duty cycle leaving them open at all times. This could result in a constant flow of fuel with the injectors not turning off. I have less than you mod wise and my stockers would run 110% at WOT.
Could be many other things but this is a place to look.
Could be many other things but this is a place to look.
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Originally Posted by Doc
What mode of fueling are we talking about here? I assume it's CLMAF?
Basically I paid Steve to tune my car to 100% and after 3 visits it is not 100%. what makes it worse is Steve doenst know how to fix this restrcition problem. So what do I do?
Heres my cars specs:
75mm lid
new style 85mm MAF
90mm NW TB
90mm FAST
AFR 205 heads 59cc
G5X4 cam
comp lifters
tr6 plugs
28.8lb injectors (which worked perfectly for the previous owner)
racetronix intank fuel pump
Kooks 1 3/4 headers
dual 3" exhaust, X pipe into 2.5" borla mufflers
asp U/D pulley
Forged Ls1 bottom end
I got the best of everything here. Do you guys see anything wrong with my setup??
I bought this motor from "mike c." from this site and the ONLY!!! thing thats different is the new style 85mm MAF and I have 3" duals. "mike c." had the older style 85mm MAF and a single cutout in the "I" pipe.
if your tuner doesnt know that big cam and heads will outflow stock injectors, not only take your money back, but also run in the opposite direction as quick as you can.
yes you're out of injectors, not by what the scanner tells you but by the laws of physics.
yes you're out of injectors, not by what the scanner tells you but by the laws of physics.
Originally Posted by RedHardSupra
if your tuner doesnt know that big cam and heads will outflow stock injectors, not only take your money back, but also run in the opposite direction as quick as you can.
yes you're out of injectors, not by what the scanner tells you but by the laws of physics.
yes you're out of injectors, not by what the scanner tells you but by the laws of physics.
also if it is out of injector, wouldnt the motor run lean???
Originally Posted by 30th t/a
could be, but how do you explain that this motor, intake to oil pan and exhaust ran these exact injectors perfectly. I bought this motor 100% complete.
also if it is out of injector, wouldnt the motor run lean???
also if it is out of injector, wouldnt the motor run lean???
What fuel pump are you running? As was stated earlier, you could easily be starving the motor at the pump and, because of that your injectors are over 100% duty cycle trying to compensate. What pump was the previous owner running? If it was a bigger pump, that could be the entire cause of your issues.
Injectors can only cycle so fast, if you're over the maximum recommended duty cycle your injectors could be stuck in an open state. Essentially the injectors are dumping fuel in as fast as they possibly can. They weren't engineered to cycle as fast as they're trying. The computer can try to compensate, but it's working with components that can only operate within a specified range. Anywhere outside of that range, they will not act as expected.
Another way to look at it. Try taking a stock bottom end of an LS1 and winding it to 10k. Somethings going to act funny if you do.
That could be what's happening with your injectors. Last edited by Rhino; Jul 4, 2007 at 01:44 PM.
Originally Posted by Rhino
I'm not trying to sound harsh, but you REALLY need to check your IDC before you go looking for anything else. I'm no tuner, I'm simply reading to learn. Everything that's been stated in this thread makes 100% perfect sense. If I recall correctly, you should really have an injector running a max of 80 to 85% duty cycle.
What fuel pump are you running? As was stated earlier, you could easily be starving the motor at the pump and, because of that your injectors are over 100% duty cycle trying to compensate. What pump was the previous owner running? If it was a bigger pump, that could be the entire cause of your issues.
Injectors can only cycle so fast, if you're over the maximum recommended duty cycle your injectors could be stuck in an open state. Essentially the injectors are dumping fuel in as fast as they possibly can. They weren't engineered to cycle as fast as they're trying. The computer can try to compensate, but it's working with components that can only operate within a specified range. Anywhere outside of that range, they will not act as expected.
Another way to look at it. Try taking a stock bottom end of an LS1 and winding it to 10k. Somethings going to act funny if you do. That could be what's happening with your injectors.
What fuel pump are you running? As was stated earlier, you could easily be starving the motor at the pump and, because of that your injectors are over 100% duty cycle trying to compensate. What pump was the previous owner running? If it was a bigger pump, that could be the entire cause of your issues.
Injectors can only cycle so fast, if you're over the maximum recommended duty cycle your injectors could be stuck in an open state. Essentially the injectors are dumping fuel in as fast as they possibly can. They weren't engineered to cycle as fast as they're trying. The computer can try to compensate, but it's working with components that can only operate within a specified range. Anywhere outside of that range, they will not act as expected.
Another way to look at it. Try taking a stock bottom end of an LS1 and winding it to 10k. Somethings going to act funny if you do.
That could be what's happening with your injectors.im running a intank racetronix. I believe the previous owner has a stock fuel pump ill find out for sure.
my a/f is 12.9 at 4900, 12.3 at 6500rpm and 11.7 at 6900. If I was out of injector, I think I would be super lean.
being out of injector doesnt mean you're out of flow, it means you cannot _control_ the flow. i've seen it many times, once computer knows it needs more than it can get, it goes stupid, and tries to dump all it can. remember that AFR is measured continously, but every explosion is separate, so if the injector is still working when valve is closed, it will still read high ipw/idc, but your explosion is going to be lean. if you got a cam with overlap, then the exhaust valve open, pull in all that puddled fuel from the intake side to exh, and v'oile, you got a lean explosion with a rich AFR.
that's just my theory, i don't know exactly what happens, but i've seen it many times on many cars with severely undersized injectors. put it on a dyno, and you'll see the power fluctuate badly, that's a much better indicator of what's going on. don't be a slave to your WB, it's just a sensor, it can be wrong, miscalibrated, clogged up, have a bad ground, etc.
if you can afford AFR heads, you can afford some injectors, i know a place that will get you flow matched 42s for 280, PM me so the mod ***** dont censor my post.
that's just my theory, i don't know exactly what happens, but i've seen it many times on many cars with severely undersized injectors. put it on a dyno, and you'll see the power fluctuate badly, that's a much better indicator of what's going on. don't be a slave to your WB, it's just a sensor, it can be wrong, miscalibrated, clogged up, have a bad ground, etc.
if you can afford AFR heads, you can afford some injectors, i know a place that will get you flow matched 42s for 280, PM me so the mod ***** dont censor my post.
Thanks Redhardsupra, that explained it better. So since im probably out of injector and my PCM sense that, the PCM is dumping in a **** load of fuel so I dont serious damage to the motor as saftey percaution. which then is showing that im running super rich. that definately makes sense.
Im going to look into some 42lb SVO's. thanks!
Im going to look into some 42lb SVO's. thanks!
Last edited by 30th t/a; Jul 4, 2007 at 05:42 PM.
heres what Steve said to this thread
"
>Your car kpa goes down at high rpm showing the motor is out of air all these replies are basic and have nothing to do with the problem that we are having these guys are talking about things that i addressed at our first tuning session in PA. We need to know why the motor is not moving any air at high rpm.The problem also happened when we ran with the original computer that the guy sent you when we dynoed in PA.This in my opinion is a mechanical restriction and not a tuning issue."
"
>Your car kpa goes down at high rpm showing the motor is out of air all these replies are basic and have nothing to do with the problem that we are having these guys are talking about things that i addressed at our first tuning session in PA. We need to know why the motor is not moving any air at high rpm.The problem also happened when we ran with the original computer that the guy sent you when we dynoed in PA.This in my opinion is a mechanical restriction and not a tuning issue."
Tell your tuner to start a session with only the Throttle Body connected, unplug everything else. It will run in SD mode since the MAF will be uninstalled, as will the intake setup. If you still run rich and the motor is choking, you know it is from the throttle body to the engine. Also try a different throttle body, does it even open all the way? I have also seen this issue before, the car needed the lid and MAF removed (althought the MAF was stock) and the throttle body was stock. Just more ideas to investigate, rather then stick to one issue. 
Good luck!
Good luck! Setting the IDC issue aside for a moment- which I totally agree with what has been suggested in this thread...
If you do a search on the various fueling senarios Open Loop, Closed Loop, Speed Density, MAF, and there various combinations you are going to find out that in your situation Closed Loop/MAF, when you punch it, the pcm defaults to Open Loop and the pcm will command the richer of two tables...
Either 1) Power Enrichment (PE) vs. RPM or 2) Commanded Fueling while in Open Loop MAP vs. ECT.
It sounds as if your tuner is not aware of this and I bet that he is just trying to manipulate commanded fueling by the PE vs. RPM table alone.
This is elementry type tuning stuff, getting the various fueling tables re-calibrated to actually put out what you command. If you can't get the pcm to command what you want in the first place then getting it re-calibrated is going to be impossible.
Either way it sounds as if you are now finding yourself in a tight situation with the time and money involved with this outfit.
I have to agree with what RHS said earlier in the thread "Run, Run away!"
If you do a search on the various fueling senarios Open Loop, Closed Loop, Speed Density, MAF, and there various combinations you are going to find out that in your situation Closed Loop/MAF, when you punch it, the pcm defaults to Open Loop and the pcm will command the richer of two tables...
Either 1) Power Enrichment (PE) vs. RPM or 2) Commanded Fueling while in Open Loop MAP vs. ECT.
It sounds as if your tuner is not aware of this and I bet that he is just trying to manipulate commanded fueling by the PE vs. RPM table alone.
This is elementry type tuning stuff, getting the various fueling tables re-calibrated to actually put out what you command. If you can't get the pcm to command what you want in the first place then getting it re-calibrated is going to be impossible.
Either way it sounds as if you are now finding yourself in a tight situation with the time and money involved with this outfit.
I have to agree with what RHS said earlier in the thread "Run, Run away!"
Regardless what its doing airflow wise, you should be able to pull fuel out of it. I've had cars were I couldnt get enough fuel IN them. Never had one I couldnt lean out.
That being said, if its building vacuum at the end of a pull, its got an airflow problem.
That being said, if its building vacuum at the end of a pull, its got an airflow problem.
well I just talked to my tuner and he says im at 70% with my 28.8 injectors 
He thinks because when we removed the 75mm lid (MAF still connected to the throttle body) and the a/f jumped to 12.8 and I gained 8rwhp….that my restriction is coming from the lid or the filter….I told him any car would do that if you remove the lid & filter…
With doing that, my a/f only leaned out to 12.8 and that’s with zero fuel being added…
He thinks because when we removed the 75mm lid (MAF still connected to the throttle body) and the a/f jumped to 12.8 and I gained 8rwhp….that my restriction is coming from the lid or the filter….I told him any car would do that if you remove the lid & filter…
With doing that, my a/f only leaned out to 12.8 and that’s with zero fuel being added…
Last edited by 30th t/a; Jul 5, 2007 at 11:36 AM.