Engine Donor '00 Mountaineer meet '91 Fox

Most 302’s with GT40 heads, Explorer upper & lower, and a decent cam will make 300+ hp at the crank. Ran three different injector size calculators and at 85% duty cycle you need 24’s or larger.

Can 19’s be used? Sho nuff but you can wipe your butt with 200 grit vs toilet paper too.

If it’s all you have send it but why would a person go too all the trouble of doing a HCI swap and then not put the correct supporting parts on it? It’s the old saying of 302 parts on a 351 make 302 power.
Understood. Appreciate ya'lls insight.
I will probably end up picking up 24's or better with matching MAF. Anybody got something laying around you wanna get rid of?!? :D
 
The main bottle neck when running stock foxbody 19’s is actually the stock 55mm MAF, not the injectors. Theres a plug and play 70mm MAF upgrade that is cheap to do. I had done it on mine using a 94 Marquis MAF. Things have changed since then but at the time, that MAF swap along with my stock Mustang 19’s worked very well. It easily supported my 302 with Explorer heads, intake, Explorer 65mm TB, headers, and 1.6 rockers. That setup pulled strong to 6k rpm no problem.

Check this thread for more details, especially post #2.


I recommend you get a genuine Ford MAF from a junkyard if at all possible.


The link in that post for the adapter is no longer good but here is the adapter currently at Ebay.

 
I dont know why that link wont post the way i wanted it to. Anyway, i copied the text i wanted to share. Here it is

Simple and cheap MAF swap...

94-95 Mustang GT MAF - $40-$100. 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

Once your replacement 70MM MAF is in place, disconnect the battery for about 10 minutes. When you reconnect the battery and start the engine, the computer will relearn the settings for the new MAF.

*1.) Metal flange adapter http://www.kustomz.com/cat3.html Buy the TR70 for $44.95. Or spend some time on eBay looking for one that may fit.

*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 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.
 
Btw, this 70mm MAF upgrade works very well with the stock air box. If you still have your stock air box, use it. If you still have your stock air box and for some reason dont want to use it, sell it to me.
 
Btw, this 70mm MAF upgrade works very well with the stock air box. If you still have your stock air box, use it. If you still have your stock air box and for some reason dont want to use it, sell it to me.
I guess I fibbed when I said "bone stock". There was/is a CAI installed so no stock box.

Thanks for the info on the MAF upgrade. There are quite a few junkyard MAFs that you referenced around me.
I basically need to decide if I want to use the 19's from the Mountaineer and do this upgrade or go big with 30's and get a MAF (like the PMAS) to match.
Where/how much do I want to spend?! Always the question :thinking:
 

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If you’re hell bent on buying new injectors and calibrated MAF, might as well go 42’s. Easily managed by the EEC and will give you room to grow. I maxed my 30’s and went to 42’s so I paid twice.
 
With a calibrated MAF you really want to stop at 30’s. It seems that any larger and they just don’t work as well. This isn’t just me as several of us on here have experienced, seen, or read the same thing from multiple sources.
 
I was one of those.

I tried to go from:

Stock engine with 2.1L KB, FMU and 19s (which worked totally fine BTW) to a calibrated MAF and 42s. It ran but it was pig rich just about everywhere and low speed manners totally sucked.

I made an appointment and trailered it 2 hours for a dyno tune. I did [not] want to pull the blower (again) to go back to the 19s. :nonono:
 
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I’m not sure about the dimensions off hand. The setup I had was moved to another car which since has been sold.

What car did you pull the MAF from in the junkyard? What are the part numbers on the MAF?
 
My son picked it up for me as he lives nearby the JY which is over an hour from me. I would measure it but don't have it in hand yet. It was off a '94 Towncar. Part number F2VF-12B579-AA
 

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