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  • Fox 5.0 Mustang Tech

Upgrade Power Improvements?

  • Thread starter Thread starter Nathan Reible
  • Start date Start date Oct 24, 2012
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Nathan Reible

Member
Oct 7, 2012
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Oct 24, 2012
#1
  • Oct 24, 2012
  • #1
Hey everyone! I'm away from home right now but bought a few things for my 89 and want to get an idea of how much power I should expect when everything's installed. I have a rebuilt bottom end with forged pistons and an aftermarket cam of some sort...the guy I bought the car from couldn't remember and lost the receipt, it's not extreme though, it's probably one of the 303s or a TFS stage one. It idles just fine at 700-800 RPMS so I can't imagine the lift is too steep. It has the stock heads which I don't plan on switching out, just a valve train upgrade and maybe a DIY port-matching and polishing, nothing more.

I recently bought a Lincoln Mk VIII MAF (80mm) with MAF adapter and K&N cone filter, a set of 1 5\8 equal length shorty headers, Bassani X-pipe and flows. How much power am I going to see out of this upgrade?

I know the throttle body needs to be switched out and I plan on doing that as well, but I'd like to get some opinions on what I should expect when I get home and bolt everything up. Thanks!
 
R

reldla1996

Member
May 4, 2011
356
22
19
Dayton, Ohio
Oct 25, 2012
#2
  • Oct 25, 2012
  • #2
While you've got it apart, you really should get a pair of aftermarket heads and an intake. Add those to the party and you'll be around 300 at the tire, or 350 at the flywheel.
 
N

Nathan Reible

Member
Oct 7, 2012
33
0
6
Oct 25, 2012
#3
  • Oct 25, 2012
  • #3
Yeah I know, heads and an intake would make a big difference, but this is a budget build for me. I just can't afford it, that's why I'll probably just upgrade the valve train on the stock heads to match the aftermarket cam, then port match them and polish them up myself...which I may go ahead and do when I have everything apart.
 

David Pepiton

Active Member
Dec 17, 2011
662
68
49
Laveen, Arizona
Oct 25, 2012
#4
  • Oct 25, 2012
  • #4
gt40p heads with intake manifold isnt really that much less then 1k for sure and would really wake the car up. heads are the single best upgrade you can make for your car.

other then what you have under drive pulleys and a 70mm TB would be great. you can get some cheaper brands just keep in mind you may need to smooth out the IAC and EGR areas to prevent it from whistling.
 
N

Nathan Reible

Member
Oct 7, 2012
33
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Oct 25, 2012
#5
  • Oct 25, 2012
  • #5
I've contemplated swapping out my heads and intake for GT40 stuff, but I'd still have to upgrade the valve train as I'm running an aftermarket cam...plus the equal-length headers I just bought wouldn't have enough clearance with GT40 heads...maybe I'll go with a GT40 intake and keep the stock heads with a valve train upgrade, that would make a difference for sure...and I'll grab a set of under-drive pulleys and a throttle body, that should round everything out nicely.
 

jrichker

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Oct 26, 2012
#6
  • Oct 26, 2012
  • #6
The MAF body and sensor are designed to match each other. Therefore you can't swap sensors between different part number MAF bodies and maintain proper calibration. The assembly is designed to match the computer’s internal program, and swapping a different MAF can upset the computer's calibration. In other words, your monster MAF probably won't match the calibration of your 5.0 Mustang computer.

The OEM Ford MAFs are not calibrated to injector size. The injector sizing is done in the computer’s internal programming. Aftermarket MAF’s “lie” to the computer in an attempt to fool the computer into changing the injector pulse on timing to match the increased airflow.

The only other MAF that is a one for one swap for a 93 and earlier 5.0 Mustang is the 94-95 Mustang MAF.

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.
 
N

Nathan Reible

Member
Oct 7, 2012
33
0
6
Oct 26, 2012
#7
  • Oct 26, 2012
  • #7
Well I've already bought the 80mm MK VIII MAF so I'll put the stock injectors back in and go with that. If it still runs like crap then I'll have to wait to get an aftermarket MAF, and if I do end up buying one, I'll get one that's calibrated for 30lb injectors so I can put those back in. Thanks for the info though!
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
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Oct 26, 2012
#8
  • Oct 26, 2012
  • #8
Your aftermarket headers will clear the GT40 heads just fine. It's the GT40P heads that have clearance issues. And if you plan on upgrading the valve train on the stock E7TE heads anyway, why would doing the same to the GT40's be out of the question?

You're leaving some cheap, easy horsepower on the table. Trash the E7TE's and go raid the top end from a '96-early-'97 Explorer. No excuse not to.

...and you have no need for anything beyond your stock 19lb/hr injectors. They'll suport 280fwhp comfortably and you're not going to make anywhere near that.
 
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Nathan Reible

Member
Oct 7, 2012
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0
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Oct 27, 2012
#9
  • Oct 27, 2012
  • #9
You make a good point...I didn't know it was only the GT40P heads that have clearance issues. Well, I may just go ahead and run a GT40 setup then...I have some time to get everything put together after all. The only reason I want to go with 30lb injectors is to prevent having to tear the top end apart again if I want to install a mild power adder later on, eventually I'd like to get around 350 rwhp out of it. It has a new Motorcraft fuel pump in it so I should be fine just upgrading the injectors. I'm also going to rebuild the AOD with one of those TCI pro kits, and it already has a solid 3.73 gear in it so I'll just get some good axles and be good there as well.

Thanks for the feedback everyone, the more I know now the less work I'll do in the end!
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
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Oct 27, 2012
#10
  • Oct 27, 2012
  • #10
Installing injectors isn't tough. Remove the upper half of the intake manifold and they're right there for access. I'd just wait unti they're needed, then go from there.
 
N

Nathan Reible

Member
Oct 7, 2012
33
0
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Oct 27, 2012
#11
  • Oct 27, 2012
  • #11
Fair enough, I'll just store the 30lb injectors for later on.
 

David Pepiton

Active Member
Dec 17, 2011
662
68
49
Laveen, Arizona
Oct 30, 2012
#12
  • Oct 30, 2012
  • #12
yeah swapping injectors is only about an hour of work once youve done it a few times.
 
N

Nathan Reible

Member
Oct 7, 2012
33
0
6
Nov 1, 2012
#13
  • Nov 1, 2012
  • #13
I'll be home this weekend, plan on installing the factory injectors, new MAF and cone filter, fuel filter and headers. I'll post the results after I finish everything up.
 
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