MAF transfer scaling

Decipha's custom GUFX strategy covers all 89-93 foxbody ecu's including the 88 mass-air california ecus.
cyear84
Posts: 2
Joined: 2023 May 19, 13:13
Location: Florence, AL
Vehicle Information: 1993 Mustang GT, 347, TFS 170, GT40 intake, Anderson N41, C3W ECU running A9L through Quarterhorse and BE

MAF transfer scaling

Unread post by cyear84 »

This question may have a simple answer, so go easy on me....I'm fairly new to tuning...

I recently got a 347 put together, and for the purposes of breaking it in, I ran the 24lb injectors that came with my car. I hadn't messed with tuning the MAF, outside of idle, because I knew my injectors were inadequate. I will also note that I had no info on these injectors other than they look like old Holley ones.

I have a C&L 80mm MAF with a sample tube that doesn't fit any of the known combinations, and I installed 47lb Ford injectors and changed all injector settings according to the Ford info.

Rather than take my 24lb MAF transfer and scale up, I took the 42lb Fox calibration and scaled it by a factor of 1.119 (47/42)

Using this transfer, it was so far off the car wouldn't run. In fact, I had to reduce the transfer by about 50% in the idle area to even get it close.

Is there some finer point of MAF tuning I'm missing here, or is this sort of to be expected? Possibly the result of a weird MAF setup? The old 24lb transfer worked perfectly the first time I fired it up.

Thanks in advance!
decipha
Posts: 5033
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: MAF transfer scaling

Unread post by decipha »

Yeah

first off the maf has absolutely nothing to do with the injectors.

put your actual injector data in and then copy your old maf transfer back in.

if it ran well enough to not need adjusting with 24s and the stock maf data then your maf just a stock replacement. load the stock maf tranafer back in and you should be good.

read the maf write up on the homepage
cyear84
Posts: 2
Joined: 2023 May 19, 13:13
Location: Florence, AL
Vehicle Information: 1993 Mustang GT, 347, TFS 170, GT40 intake, Anderson N41, C3W ECU running A9L through Quarterhorse and BE

Re: MAF transfer scaling

Unread post by cyear84 »

I figured I was probably over-thinking it. Would that be an indication that the MAF is intended for 19 or 24lb injectors? It's an 80mm C&L with a .650 tube, which doesn't match any calibration info I was able to find.
decipha
Posts: 5033
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: MAF transfer scaling

Unread post by decipha »

If it ran reasonably well with the stock maf transfer then its probably just a stock replacement.

again read the maf write up its all layed out for you there
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