TwEECer R/T Tuning Help on 96 GT... Take a Look...

[WA2FAST]

Hello there, I need help with tuning a 96' GT in a few different areas. It's a 96' GT 5-speed, TwEECer R/T for tuning, PI Intake, PI Cams, P1SC @ 10psi, 3 core intercooler, lots of other stuff... I have a few things I would like to "fix" in the tune and the car's general attitude. We just swapped out the cams and intake on it, we got the kit from Livernois Motorsports with the plates... the NPI heads are ported and the plates have been port matched to them. Everything is together and needs the final tune. I need to know what the intake manifold volume is for a PI intake and I need the injector timing table for sure for a 99+ 2v Mustang as well so that the injector timing events are correct. These are my general questions...

1) What is the PI Intake Manifold volume?
2) What is the injector timing table on a 99+ 2V Mustang (PI Cam'd car's injector timing table)?
3) How do I get the throttle hang to go away so that it acts more like a A9L car (5L Mustang)?
4) How do I get the "popping and backfiring" to go away while decellerating... is it timing on the bottom row of load maybe?

I would greatly appreciate some help... I've been looking for the TwEECer forums to come back up and they haven't yet and I need to get this car tuned and working good. Any help here is greatly appreciated. Thanx guys!

[Sendero]

Ohhh, this would be a great question for Boss96GT. Does anyone know how to get in touch with him?

[QWKSNKE]

I am sure Bob will stop by the forums today

[boss96]

I don't have the inj timing values for a 99+ car, the software does not list it that I can see. However, I would not worry much about it, if you like you can run Clints Eecanalyzer program if you know your cam specs and it will give some suggestions. Man vol is 5.75 for a PI.
Popping on decel is made worse when you have no cats in the exhaust, you can't get rid of it entirely buy the usual maf curve adjustments help. Sometimes increasing the "neutral idle air" values higher will make some of that go away.
Hanging idle is harder, make sure the throttle body has not be fooled with, otherwise you will have to mechanically adjust it. This means it should idle about 100 rpm lower than the desired idle speed when the IAC value is unplugged. After that you can disable the values in the "dashpot pre-position" function to eliminate some of the hang, you can reduce the air value under "neutral idle air" in the 1000 rpm range to get the 1000 rpm idle while the car is moving when coasting to at least be close to 1000 instead of higher.
Finally, you can increase the values in "dashpot decay" function to make the idle come down faster although this mostly effects the car when it is not moving, not during coastdown.
After all that you will find that if you are running the eec in adaptive mode (normal) then the eec will be adjusting the iac values anyway to make it optimum so you may end up chasing your tail for awhile :)
Bob

[93Cobra#2771]

Figured bob would be the one to help on this one. :nice:

[WA2FAST]

Great! Thank you for the replies... I got the car running pretty good... it's a monster compared to before with those PI cam's and PI intake... WOW did it ever pick up a ton of power. The stock Manifold (NPI) volume in the EEC is set to 9.75... I figured it would be larger due to the larger intake runners... so I just guessed and set it to 12 and the car runs great. Is it really 5.75 on a PI car? Where is all of that extra volume coming from in the NPI car... everything about the PI intake is bigger and visually looks bigger.

Thank you for the help on the other functions... just trying to change the "attitude" of the car... this car has no cats and dumps... the exhaust note at 1500 is rediculous and is there constantly when the car is either rolling or you blip the throttle... it just hangs there for a while then goes down to it's normal idle speed. Very annoying. The popping... again, that's just an annoying thing too... not a big deal. Thank you very much for the help on those areas though, I will let you know how it goes.

I am having an issue with datalogging on this car. Outside of being extremely glitchy and getting crazy readings for 1 frame at a time every 5 seconds or so... the MAF is being logged all wrong. It is 2 decimal places over in the datalog. For example, MAFV is .700-.800v at idle, it's being logged as .007-.008v. That is a big problem for trying to use Clint's software to help with the injector timing or anything else for that matter that needs MAFV. I can make sense out of it logically... but I would like to have it correct. Any ideas as to what is going on here?

Also... in the CDAN4 strategy... is the injector timing leading edge, trailing edge, etc... how do I set it up for that? I used to know that stuff like the back of my hand, but I can't for the life of me remember what the A9L is now and what the CDAN4 is when it comes to setting up the injector timing.

Thank you again guys!!!

[boss96]

I don't know about the inj timing being leading/trailing but I do know that I have done a few headswaps on 96-98 gt's and you did not even have to tune the car . The few guys who went for dyno tunes after the swap saw no real gains anyway so I would not worry about the inj timing.
As far as Calcon goes, there are some glitches with it such that some things can't be logged. If you can log maf kg/hr values then you can at least make changes for your maf values. If you want you could also call Mike Glover and see if he has anything for you on that. The values jumping around from frame to frame are normal though.
Man volume is a type of accerator pump scalar, if you increase the value the tip in fuel is reduced, not increased, going to a lower value will give you better tip-in. I have no idea why it works the opposite of what you would think but that's how Ford did it. On other strategies it works the other way, you have to try it and see.
Bob