1988 MAF Conversion

[dangrego]

Hello, looking for guidance on correct size MAF and correct computer for converting an '88 5.0 EFI manual transmission to Mass Air...I already did the conversion two years ago with crappy results and am considering throwing out the remanned A3M1 computer for something different and also replacing my 75mm PMAS MAF meter (yes, cal'd for 24 lbs) with a different brand and/or size?

Details:

24 lb injectors
70mm throttle body
BBK cold air induction
Edelbrock RPM Performer II upper and lower intake

Any insight out there regarding?

 

[dangrego]

...another thought, the computer used for my unsuccessful MAF conversion came out of a car with 19 lb injectors factory...do i simply need to find a computer that came factory for cars like the cobra which used 24 lbs?

 

[liljoe07]

93 Cobra Computer was used with 24lb injectors.

 

[jrichker]

Using 24 lb injectors with your setup will not bring any HP gains with it. The stock 19 LB injectors are good to 260-280 HP with some safety margin.

Use an aftermarket MAF that matches the injectors. Mistmatches just mess up the air/fuel mixture.

The best MAF for your combo would be one of the following:
94-95 Mustang GT MAF - $40-$100 at the junkyard. It is 70 MM instead of the stock 55 MM on regular stangs built prior to 94. It uses a slip on duct on the side that goes to the throttle body and a 4 bolt flange on the other. You need a flange adapter to fit the stock slip on air ducting that goes to the air box. Wiring plugs right in with no changes. *1 *2

*1.) Metal flange adapter Kurtz Kustomz Motorsports, Inc. KKM Buy the TR70 for $44.95. Or spend some time on eBay looking for one that may fit.
Try AutoZone and ask for 81413 - Spectre / 3 in. Aluminum Intake Mass Air Flow Sensor Adapter at $12.00. You may have to order it online.

*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1994-95 Mustang 3.8L F2VF-12B579-A2A,
1992-94 Crown Victoria 4.6L F2VF-12B579-A2A,
1994-95 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1992-94 Town Car 4.6L F2VF-12B579-A2A,
1992-94 Grand Marquis 4.6L F2VF-12B579-A2A,
Evidently the –A1A, -A2A, AA, etc. on the end of the part number is a minor variant that did not change the operating specs. You should be able to ignore it and have everything work good.

 

[vristang]

Hello, looking for guidance on correct size MAF and correct computer for converting an '88 5.0 EFI manual transmission to Mass Air...I already did the conversion two years ago with crappy results and am considering throwing out the remanned A3M1 computer for something different and also replacing my 75mm PMAS MAF meter (yes, cal'd for 24 lbs) with a different brand and/or size?

Details:

24 lb injectors
70mm throttle body
BBK cold air induction
Edelbrock RPM Performer II upper and lower intake

Any insight out there regarding?

So, how was the MAF swap unsuccessful? What problems are you having?

If the MAF meter you have is properly calibrated for your injectors and ecu, then you shouldn't be having issues with it.
Did you buy the MAF new or used?
Have you double checked the part numbers with the manufacturer to verify you are using the right meter?


When running 24's one of the best ways to do this is by using the 93 cobra setup.
ecu - X3Z
Inj - 24Lb
MAF - F1SF/afh70, which is in a 70mm housing.

However, this involves buying more parts, which I would recommend until you have positively identified the source of the problem you are having.

jason

 

[dangrego]

jrichker, am temped to go back to 19; however, I want to make sure that 24 is not still good since I have, as not mentioned earlier, reworked heads with oversized valves etc and upgraded headers/exhaust also...any problems forseen with using the '93 cobra computer and just staying at 24 lbs?

 

[vristang]

jrichker, am temped to go back to 19; however, I want to make sure that 24 is not still good since I have, as not mentioned earlier, reworked heads with oversized valves etc and upgraded headers/exhaust also...any problems forseen with using the '93 cobra computer and just staying at 24 lbs?

The 93 Cobra computer will require a 93 Cobra MAF.

With 24's, that setup will work well.

 

[dangrego]

howdy again, would a 75mm MAF work as opposed to a 70mm? (i have one ordered and it is a 75mm...if it is prudent, I will surely send it back for a 70mm). Also, fyi, my TB is a 70mm.

 

[vristang]

howdy again, would a 75mm MAF work as opposed to a 70mm? (i have one ordered and it is a 75mm...if it is prudent, I will surely send it back for a 70mm). Also, fyi, my TB is a 70mm.

It isn't so much the size of the MAF that matters, but rather the calibration.

Did you order the MAF for an A9L ecu, or for a X3Z ecu?
They aren't the same calibration...


No offense dude, but you're kinda bouncing all over the place.

What is wrong with your car? Diagnose the problem before dumping money at it...
Folks have asked some specific questions in this thread, trying to help you get things figured out.
You've pretty much ignored all of it... kinda rude?

 

[dangrego]

sorry 'bout that.... Currently running an A9L equivalent computer with 24 lb injectors and a MAF cal'd for 24 lbs...have been having really bad idle surge and running super rich even after all the diagnostics, sensor checking/replacing, and tuning. Anyways, my MAF got crushed accidentally the other day so I have to throw money at a new one and think I will just stay with the 24 lb injectors and 75 mm MAF....guess I do need to make sure it is cal'd for the '93 computer that I plan on aquiring as well. thanks again! any thoughts? V/r

 

[Mustank]

If you already have an A9L ecu, there's no reason to change it. Just get a new MAF then double check all of your wiring.

Have you gone through the Surging Idle Checklist?

Surging Idle Checklist

edit: Wait...what do you mean by A9L "equivalent"?

 

[dangrego]

oh yeah, i've ran the surgin idle checklist a couple of times....the A9L equivalent is a Remanned A3M1, F3ZF 12A650 DB...got it from Brother's Performance.

 

[liljoe07]

Posted via Mobile Device

Did you solder you connection on the MAF conversion?

 

[dangrego]

yes, not at first, but a few weeks ago, i went through and redid all my connections the right way with solder, but didn't solve the problem.