nick Ritter

iTrader: (3)

hello all

I'm just putting the finishing touches on my build the setup is as follows

1990 mazda rx7 fc

2007 Lq4
BTR cam stage 4
springs
push rods
stock 317s
professional products 96mm intake ported
nw 102mm tb
LT headers
OEM corvette LS7 otr intake common on these cars

I have a question in regards to the maf tuning tables
I'm running a P59 PCM doesn't seem to have very many options for editing things as I thought so far I have only changed the injector data and it runs but like crap

but I tried to copy and paste the maf calibration tables and it will not paste over because the stock 08 vette ls3 bin exceeds the stock P59 limits heres some pictures of what I'm talking about read the bottom and notice the ranges








does anyone know how I can over come this issue ?

or have links to help

I'm also treying to tune in a choppy idle but I cant find a good video/write up for the gen 3

T/A KID

iTrader: (12)

If you have hpntuners I could help

nick Ritter

iTrader: (3)

i do have it, let me know its urgent

gametech

iTrader: (1)

Ditch the MAF for SD only. People with tuning software don't need the redundancy offered by factory tune setups. If you decide you want multiple backup tuning systems later, you can always use the time between now and then to figure out any issues you have with the current MAF hardware.

nick Ritter

iTrader: (3)

I was looking into this option I would really like to retain the maf for drivability
I'm sure theres a way around this that's simple

gametech

iTrader: (1)

There may very well be a simple solution to use the ls7 MAF. However, until you find the proper solution, SD only causes absolutely no drivability issues. It is, however, somewhat more time consuming to fully tune. This should not be seen as a drawback, however, because you would want the SD to be fully tuned in addition to the MAF once you finish your project. This would give you the equivalent of a full factory capable tune.

nick Ritter

iTrader: (3)

Tuner said the exact opposite

maf cars will run better in any condition and drivability will improve along with a nice lopey idle

gametech

iTrader: (1)

Your tuner is either lying, lazy, or incompetent. My vote is probably for lazy, because a full SD tune takes a lot more work than a MAF tune.

rpturbo

iTrader: (47)

I can say mine is SD tune, because I have absolutely no drivability issues, and when I was done with that, I was too lazy/seen no reason to do the MAF. It does take a little while to get it dialed in though.

NicD

iTrader: (7)

You need to calibrate the MAF no matter what so just double the stock MAF table and start there. There are plenty of downsides to having it run in speed density compared to a MAF and I would hope that people realize that actually measuring the mass air flow compared to estimating it is going to be more accurate under changing conditions. It's why I generally only recommend going speed density when necessary, ie exceeding airflow limits, intake air reversion from large cams, etc.

G Atsma

^^^^ Exactly! SD is doing what it is "supposed to do", while MAF is reacting to real conditions.

gametech

iTrader: (1)

While the difference is minimal, you must consider the fact that MAF sensors react more slowly to changes than MAP sensors. This is very likely why GM uses the MAF more for steady state and the SD more for quick transitions at low airflow conditions. I stand by my theory that the OP would be best served going ahead and getting his car on the road in SD while figuring out the MAF situation. Once sorted, the MAF can be added back in to have a full factory style proper tune.

G Atsma

I DO totally agree with your reasoning; get SD tuned to within an inch of its life (lol), then when desired go to MAF. That way all bases are covered. Good thinking!