Mustang Tuning / AFR / Timing Help!

Stock maf is a 70mm with a divide in the middle. The thing to look at is the flow rate, and the factory 94-95 maf is on the low end and IIRC less than a 65 Pro-M/PMAS flow rate. One needs to log and see were they fit if they are pegging a maf out, its the only way to know for sure. I would assume the combo in question would peg the stock 94-95 meter.

If one has a tuner like QH or tweecer R/T I would look for a factory Ford MAF or the SCT MAF that has 30pt transfers like stock. Then I would look at a Pro-M/PMAS not because its a bad maf just the others are going to be a little easier to tune since you dont have to convert a 10pt transfer with the Pro-M/PMAS to 30pt. Its not that hard to convert a 10pt to 30pt but if you can skip that step...one less thing. Then there is the "cheat" for the injectors and if one ever changes injectors things can get funky quick unless you send it back and the further you get from the stock inj. the bigger the chance you will be sorting out a driveability issue somewhere on our load based setups.
 
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I also do not see how the little OEM meter will support such a combo :scratch:

You don't have to be afraid of a Pro-M with a cal :nono:
as long as
You load in the curve and get it fairly close ;)

Like Greg said :nice:

Running aftermarket meters in cheat mode makes many things be
quite HOSED in our 94-95 load based pcm's :Word:

Grady
 
I also do not see how the little OEM meter will support such a combo :scratch:

You don't have to be afraid of a Pro-M with a cal :nono:
as long as
You load in the curve and get it fairly close ;)

Like Greg said :nice:

Running aftermarket meters in cheat mode makes many things be
quite HOSED in our 94-95 load based pcm's :Word:

Grady

Grady I just tuned a 95 cobra the other day with a stock meter and 24s , built 306 with E cam (small I know) , procomp 210cc heads , trickflow R series intake , had to fatten it up some but the meter was at 4.64 volts at 6200 rpms is when the cam ran out of steam
 
Grady I just tuned a 95 cobra the other day with a stock meter and 24s , built 306 with E cam (small I know) , procomp 210cc heads , trickflow R series intake , had to fatten it up some but the meter was at 4.64 volts at 6200 rpms is when the cam ran out of steam

That does not surprise me at all

Depending upon combo parts chosen ..........
the little OEM meter will go farther than what many suspect

I'd guess a ballpark value of about 290 to 310 sae to the wheels :shrug:

Of course ... it all depends upon airflow past the meter which is dictated
by heads, intake, cam, bla bla bla :)

If you look at my sig combo ........
I barely pegged the OEM meter and that was with me upping the maf volts
in the pcm to 4.999999 for extended range

It just seems to me with the additional airflow of the cubes of the original
poster ... the meter would run out room :shrug:

Before I go ... It might be helpful to make one thing clear to those who don't
have pcm access here

The talk here is all about one being able to adjust with the pcm the airflow
values of the meter to reflect changes made by the hot rod parts

We are not talking about using only mechanical methods such as
a different caled meter :nono:
no matter if tubes like with the C&L or electronic like with Pro-M

Bottom line is ... You'll run outta inj B E F O R E you run outta meter ;)

Grady
 
I guess its worth mentioning here... Set the timing at 10 base... actually i wasnt far off from where we determined it to be running nice... i think we were at about 12*

I put a filter on the maf and backed off on the idle screw a tad and with the 24 lb Pro M maf and no Quarterhorse the AFR was pretty tame. I have not started data logging yet but while chris was driving i was looking at the meeter.

15.5-16.6ish at idle...
cruising its 13.8-15.5ish
At wot i saw it as low as 12.7 to about 14.3

So its kinda fat uptop... im sure i can adjust when i get the QH back...

fwiw i think there is some mixups with what people think is my combo

my combo is as follows:
306
0.030 keith black flat top pistons
TFS KPI high ports
TFS track heat intake manifold
Wolverine 1190 cam
24lb injectors
24lb pro m maf
Accufab 1 3/4'' long tubes with 3'' collectors
70mm Accufab tb and spacer.

By no means nothing far out of the ordinary... Only difference is i have a "bigger" set of heads then most.

Ill probably only put down 290-300 rwhp
 
In a way ... AFR during closed loop is kinda pointless cause the O2's are
in control :crazy:

You can look at the K's to see if they are adding or pulling fuel ;)
then
You can adjust meter airflow or inj values

Of the two ... I think using inj values produces a more stable tune :)

Grady