Hptuners, injectorpulse vs MAP = PCM FMU? - Tuning Forum

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Hptuners, injectorpulse vs MAP = PCM FMU?
Saturday, May 13, 2006 11:45 AM
well basically I have just been screwing around with the software, and I have not tested anything on the car yet, as I am at work till june.1. Pretty much the gm s/c reflash is good for 14.7 (1 bar) boost, and is good for lowerer CFM, and the only time I really noticed that it leaned out without FMU was not RPM consisant rather MAP related. so I found this in the software and was curious if anyone has tried this, or if my logic is completely messed up.

The first pic is the factory setting for the GM s/c which is the same for the NA setup with differences in the 100kpa VS 210kpa field.




in this second pic I made some changes that I HAVE NOT TESTED, but made them noticable so you would see what I was getting at. The theory I am working on is as the MAP pressure goes up the fuel delivery goes up aswell... working simular to the mechanical FMU on percentages of boost, and % of pressure raised.... only in this case instead of pressure we use pulsewidth. So when tuned with a wideband it would appear that you could simply add fuel according to MAP.




HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED


Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Saturday, May 13, 2006 12:12 PM
You want to tune a car using the VE tables, not the injector pulsewidth modifier table. The only way to get it truely accurate is to datalog, then change, and repeat.

Get some logging before changing the fuel delivery stuff.





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Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Saturday, May 13, 2006 12:12 PM
This looks like an excellent find. Those settings will probably turn out to be rich but they will likely give you a starting point. If you have a dyno sheet or know what the AFR was when you were lean, you can figure out roughly what the correct multiplier should be. For example, if your AFR was 13:1 and you want to see 12.2:1, do this: 13:1 / 12.2:1 = 1.066. This gives you the percentage difference in fuel you need to make 13:1 AFR into 12.2:1. So the maximum multiplier you'd start with is 1.066, which is approximately 7% richer. Your entries of 60% (1.06) are good for changing 20:1 afr to 12.5:1 AFR.

Good luck.
-->Slow
Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Saturday, May 13, 2006 12:17 PM
Quote:

but made them noticable so you would see what I was getting at


yah I can't wait to get home to do some real tuning, this table might really aid in tuning :shrug



HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Wednesday, May 17, 2006 3:46 AM
Quote:

Quote:



but made them noticable so you would see what I was getting at


Didn't realize you were talking about the actual numbers... thought maybe the size of image. Oh, well.

Quote:

You want to tune a car using the VE tables, not the injector pulsewidth modifier table.


Well, if you follow GM's lead, the OBDI 2 BAR calibrations designed and used in the '80s and '90s do exactly what was asked about.
The VE table covers 20 to 100 kPa, then a base pulsewidth VS MAP multiplier is used for MAP > 100 kPa. This is a sound Idea. If this table functions as the name implies, it will allow correct fueling on a turbocharged car, where alpha N tuning is not appropriate.

Quote:

The only way to get it truely accurate is to datalog, then change, and repeat. Get some logging before changing the fuel delivery stuff.

Logging and reviewing the runs is important. You can't do enough logging.

Please post updates if you try adjusting this table.

-->Slow
Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Wednesday, May 17, 2006 6:31 AM
I'll be home in exactly two weeks now, I'll be sure to post some stuff up once I get working on it, might only be june.1/2



HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Wednesday, May 17, 2006 1:29 PM
very good find! do you know if this table is available on all supported year J pcm's (97-05)?



Sven you totally quarterloafed your computer..
Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Wednesday, May 17, 2006 1:45 PM
no idea at all, this is a 2002 HPT file I have been screwing around with, I have a 2000, but I think they should be pretty close, GM released a couple of different calibrations, I hope this is the most updated one :shrug


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Wednesday, May 17, 2006 1:53 PM
thanks for the info!



Sven you totally quarterloafed your computer..
Re: Hptuners, injectorpulse vs MAP = PCM FMU?
Wednesday, May 17, 2006 1:57 PM
it should definately be tested whether this table is used by the pcm at all.. hopefully it can be used in the way we're hoping. it could make the VE and this table a decent combo for tuning our fuel.



Sven you totally quarterloafed your computer..
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