Engine Any gains from Cobra MAF and larger TB?

Blue_67Vert

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This engine is in my ’67 Mustang.
5.0HO, Ford EFI (A9P), MAF, Stock intake manifold, EGR, no other smog equipment (no cats), underdrive pullies, elec. fan, No PS, no AC, shorty headers, 2.25” exhaust, AOD, 3.55 LS Rear

I already have a Cobra MAF in my parts bin. TB I will have to buy.

I do have other parts that benefit from the larger MAF/TB but I am not planning to install them any time soon. GT40Y303 Heads, Explorer Intake (external EGR), E303 cam (TBD whether to use use the E cam or keep the stock HO cam).

So my question is, would I see any gains installing the just the MAF/TB in the short term?
 
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KRUISR

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I would think MAF/TB on otherwise all stock engine, maybe a couple HP. Intake and heads are your biggest bottleneck.

For a few more (and still keep a simple swap), put the Explorer intakes on, 65mm (cheap one from an Explorer with a very simple conversion to work on Mustang) or 70mm TB and MAF.

When I first got my car back on the road, I had a stock long block (bottom end, E7 heads and cam) with 1.7RRs, Explorer intakes and 19lb injectors, Explorer TB (65mm), stock EGR, C&L 73mm MAF and shorty headers, full 2.5" exhaust with cats, 3G alt and electric fans. I am a A9P computer and AOD as well (3.73 gears though). It was a fun drive and I believe (no dyno to prove) I was 275-285 HP at the crank (about 240 at wheels). Horsepower estimates based on speed/RPMS at end of a 1/4 mile run and weight of the car crunched through online calculators.
 
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deathb4dismount

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I would think MAF/TB on otherwise all stock engine, maybe a couple HP. Intake and heads are your biggest bottleneck.

For a few more (and still keep a simple swap), put the Explorer intakes on, 65mm (cheap one from an Explorer with a very simple conversion to work on Mustang) or 70mm TB and MAF.

When I first got my car back on the road, I had a stock long block (bottom end, E7 heads and cam) with 1.7RRs, Explorer intakes and 19lb injectors, Explorer TB (65mm), stock EGR, C&L 73mm MAF and shorty headers, full 2.5" exhaust with cats, 3G alt and electric fans. I am a A9P computer and AOD as well (3.73 gears though). It was a fun drive and I believe (no dyno to prove) I was 275-285 HP at the crank (about 240 at wheels). Horsepower estimates based on speed/RPMS at end of a 1/4 mile run and weight of the car crunched through online calculators.
That’s a generous estimate
 

KRUISR

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You try then... 3750 lbs, 4600 RPM, (calcs to 96 MPH - same as speedo), launch off idle, 3.73s, 26.2" tire. Try various calculators and what do you get?

Current setup ... 3750 lbs, 4950 RPM (calcs to 103 MPH), launch off idle, 3.73s, 26.2" tires. I get 330-350 range.
 

Mustang5L5

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To run the Cobra MAF, you really need 24# injectors and the cobra ECU as well. It’s a matched combo. It won’t Work with the A9P.

with the stock intake, I wouldn’t bother. Buy a TB and instal when you do your intake.
 
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deathb4dismount

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You try then... 3750 lbs, 4600 RPM, (calcs to 96 MPH - same as speedo), launch off idle, 3.73s, 26.2" tire. Try various calculators and what do you get?

Current setup ... 3750 lbs, 4950 RPM (calcs to 103 MPH), launch off idle, 3.73s, 26.2" tires. I get 330-350 range.

220ish
 

Blue_67Vert

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To run the Cobra MAF, you really need 24# injectors and the cobra ECU as well. It’s a matched combo. It won’t Work with the A9P.

with the stock intake, I wouldn’t bother. Buy a TB and instal when you do your intake.
I thought the injector tune was in the ECU. The Cobra ECU is programmed for 24# injectors. A9P is programmed for 19# injectors.

The MAF just measures the airflow and reports that the ECU. The Cobra MAF could be used with the A9P and 19# injectors, which is what I was planning to do.
 
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Mustang5L5

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I thought the injector tune was in the ECU. The Cobra ECU is programmed for 24# injectors. A9P is programmed for 19# injectors.

The MAF just measures the airflow and reports that the ECU. The Cobra MAF could be used with the A9P and 19# injectors, which is what I was planning to do.

You are right except the standard 5.0 55mm MAF and the Cobra 70mm MAF have different MAF transfer curves. The reason for this is because the 1993 Cobra MAF was actually taken from the 1992-95 Thunderbird Supercoupe, so the calibration was different for the SC. Ford just compensated in the ECU programming.

What that means is that at the same flow through the MAF, you are going to have two different output values between the two meters.

So they are a matched set that cannot be interchanged without tuning

A9P + 19# + 55mm MAF

X3W + 24# + Cobra 70mm MAF

If you want to run 24# injectors, you either need a tune for the ECU, or an aftermarket MAF calibrated for 24's
 
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KRUISR

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I don't have the dimensions in front of me, what is the ID of the flow tube on the Cobra MAF? Also what is OD of flow tube?

1620336016379.png
 

Blue_67Vert

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My 19# injectors are new. Those are staying. I was going to
You are right except the standard 5.0 55mm MAF and the Cobra 70mm MAF have different MAF transfer curves. ,,,,

What that means is that at the same flow through the MAF, you are going to have two different output values between the two meters ,,,,

If you want to run 24# injectors, you either need a tune for the ECU, or an aftermarket MAF calibrated for 24's
No bueno for me. But that makes sense.
I was mostly looking to add the MAF and TB ahead of installing the Intakes and Heads so as to not introduce so many changes at once.
My 19# injectors are new and are staying.
Thanks for the explanation.
 
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Mustang5L5

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If you stil with the 19# injectors, you can use a 94-95 Mustang MAF. It’s a 70mm MAF as well but it’s transfer curves are close to that of a fox. I believe you can use a 91-93 cougar/tbird MAF too as it has a flange that will mount in the stock fox airbox. The 94-95 MAF needs an adapter flange to work.

I also think you can take the 94-95 electronics and install them in the 93 cobra housing as the 70mm MAF internals are the same between the MAFs listed. This is unconfirmed though.

Stamped on the electronics is a code such as AH55 or AH70 indicating they are meant for a specific meter size. Back in the 80's and 90's, Ford did standardize a few of the meters other than flanges and bosses for specific mounting in certain vehicles. Because of this, i do believe there is some interchangeability with the housings. The electronics, however, must be compatible with the ECU

I’ve run a 94-95 GT MAF with adapter flange on my car with A9L and 19s for a few years now. Runs beautifully.
 
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Mustang5L5

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Just to expand, and go slightly off topic.

This is a 95 Thunderbird MAF. The electronics on this are useless to us Mustang/302 folk, but the housing is virtually identical to the 1993 Cobra MAF. It's a 70MM unit, has the correct inlet/outlet configuration and even the 3-post mounting (that usually isn't used). I am aware of one person who took this housing, and installed a 94-95 Mustang MAF electronics on top and ended up using it.


Here is a 94-95 Mustang. The internal features are the same as the above t-bird MAF and the cobra MAF, but you can see it uses a different mounting flange. The electronics however do match up and function with the A9x ECU however. I am using this exact MAF, with an adapter flange. However if i had found a check tbird housing (above) i would have made the swap.

Used examples can be had rather cheap, and the adapter is usually $10-20.


What makes it pricey is mixing and matching the housings and electrnics. In your car, with the 93 cobra MAF, i think all you need to do is track down the 94-95 electronics and swap it on.

I do have my 94-95 SN95 MAF off the car, and can get a measurement later to confirm it does match the 93 cobra MAF diameters.

The 94-95 Mustang MAF electronics are F2VF-12B579-A2A. This was used on a few cars in the early 90's. The housings unfortunately don't have unique part numbers.
 
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Blue_67Vert

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Thanks for the info. I'll probably just sell the complete Cobra MAF and ECU together since they are matched. That should fund a SN95 MAF and TB and maybe even an intake manifold. The Exploder intake I have now is non-EGR and I will probably want to keep the EGR.
 

KRUISR

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Picture223.jpg
Actually looking for dims on the flow tube (circled above).

I did some quick math and the 70mm pictured above might only be marginally bigger than the stocker. The tube width and ID can help me finish off those calcs.
 

Blue_67Vert

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Picture223.jpg
Actually looking for dims on the flow tube (circled above).

I did some quick math and the 70mm pictured above might only be marginally bigger than the stocker. The tube width and ID can help me finish off those calcs.
thingies aren't long enough to measure ID perfectly, gauge not exactly perpendicular, but I get ID 9.75 OD 11mm