89 gt upgrades where to start?

Skip the underdrive pulleys unless you live in Canada and don't have A/C. They tend to make things overheat without a lot of other things like a $250 radiator to help cool the engine.

On a budget? do the junkyard upgrade...

Gears - 87-88 T-Bird Turbo Coupe rear axle - 10.5" vented disc brakes and 3.55 or 3.73 gears in one package for $125-$300. Uses the stock 4 bolt lug pattern. Add another $100-$200 or so to complete the brake upgrade.

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

95-97 Ford Explorer intake manifold & throttle body $150-$300. The intake manifold flows 220 CFM +, much better than stock. Throttle body is 65 MM, bigger than the 60 MM on stock stangs. I got a 96 with EGR passages that match the stock setup, so my smog gear works just like factory. You’ll need a 65 MM EGR spacer & new gaskets for $65-$90 so you have a place to mount the EGR & throttle linkage.

3G alternator from 94-95 Mustangs or other Ford. $20-$120. A must have to make the electrical system work like it should or if you have an electric fan. You’ll need a 4 gauge power wire and a 125-135 amp fuse to go with it - about $25- $50 for the wire, fuse holder and fuse.

Lincoln MK VIII electric fan -$40-$160. Free up some HP by not having to drive the stock fan. The 3G alternator upgrade is a must have prerequisite before you do the MK VIII fan. You won’t have enough electrical power if you don’t do the 3G upgrade.

Aluminum driveshaft: (courtesy of shawn13) It needs to be from a 92-95 AeroStar AWD or Electric 4 wheel drive. It measures 45 ½” center of the front U-joint to center of the rear U-joint. You will need the U-joint, part #PUJ353 from NAPA. The Canadian NAPA pat number is 1-0134BF. It should bolt right up after the U-joint swap.

bhuff30b’s input: However, no information was given for the 96-97 AWD aerostar driveshaft. I picked up one of these this weekend, for about 20$ from the local scrap yard. It already has the proper 27/28 spline yoke and needs no modification to install on a mustang. Also, the ends are securely welded on, as opposed to previous driveshafts which were pressed on. I'm not sure if the 92-95 driveshaft is pressed or welded though.

Note: This driveshaft is not an exact duplicate of the Ford Racing part. It is 3” in diameter while the Ford Racing part is 3.5” in diameter.

*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.

Is the car AOD or 5spd? I have never had issues with underdrives on any of my foxbodys, and gained around .15 and 1-2 mph at the track. Back in '99 or so I track tested alot of different parts with my '93 GT. I started with a stock 93 GT AOD and by the time I sold it around 4 yrs ago it had went from a 14.9 car to a 12.7 car on a tight budget.

Before doing any mods, personally I'd make sure the cooling system is up to par. I can see how under drives might cause issues on an older car with a weak cooling system.

Free mods 1st: 12-14* timing & remove air silencer plus a drop in K&N

Don't waste $$ on any intakes, I have tried them and at the track there were no gains over a stock airbox with removed silencer. Even with a 331 stroker I saw no gains to be honest. Again, this is track experience no seat of the pants BS.

I ran 13.80@100 and trapped as high as 103.1 with my 93 GT and it had:
stock 3.27 gears (was an AOD car), full exhaust (not needed to runs 13's), ASP pulleys, and a 70mm 93 Cobra MAF. The car was around 3500lbs give or take.

The 70mm 94 up MAF like mentioned above is a better option over the 93 Cobra due to the transfer function being a little closer but still off from the stock 55mm meter. I have not seen big gains at the track from meters on an otherwise stock car and I tried 75mm Pro M and 76mm C&L kits back in the day.

My cousin ran a 13.9@100 with his 89 GT still with stock headers and stock 55mm MAF! 150k mile car! He too had 3.27 gears, an offroad H-pipe, catback, and pulleys. Thats IT!

The most important thing I will say from owning around 15 of these cars since the 90's is to make sure the car is running RIGHT. New plugs, wires, cap/rotor, fuel filter, etc. Check the timing and make sure the car is not running too hot. I usually stick a new waterpump and a 180* thermostat since most cars have been neglected. Radiators have a tendency to plug up in the lower part as well. I have had great luck with aftermarket 3 core copper radiators.

Sorry for the long reply...good luck!!

mac_55 said:

yes it is an automatic , and the cooling system is all only a year old

what about a quick cam or head swap from another 5.0L or is my H.O. good enough

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What is done to it now?

STOCK CAM, do not waste time/$$$ with changing the cam out especially with the AOD. You will just run slower.

The best mod for the $$ would be gears. The 1st mods I'd do is 3.73 or 4.10 gears and a valvebody for the AOD tranny.
VB AOD

Before messing with anything else other than the free mods do gears and valvebody.

EXAMPLE:

My 93 GT AOD with optional 3.27 gears 14.90@94 with pulleys & K&N on 17" rims

added FULL MAC exhaust and cold air 14.84@96

I gained MPH showing a HP gain but lost lowend so my trap speed was not much better and the car felt slower on the street.

373's or 410's(your preference).. cold air, jlt's are best IMO. And if you want some serious power, set aside about 1500 and get a good set of heads. you'll love em. And cant go wrong with a short shifter.

cammed89lx said:

373's or 410's(your preference).. cold air, jlt's are best IMO. And if you want some serious power, set aside about 1500 and get a good set of heads. you'll love em. And cant go wrong with a short shifter.

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It's auto not 5spd. A cold air intake does nothing for power over a stock airbox with removed silencer and drop in K&N filter. Unlike the 94 up the 86-93 have a decent airbox design and already pull cold air from inside the fender.

cammed89lx said:

373's or 410's(your preference).. cold air, jlt's are best IMO. And if you want some serious power, set aside about 1500 and get a good set of heads. you'll love em. And cant go wrong with a short shifter.

Click to expand...

JLT doesnt make fox CAI, if you really want to get a CAI get a Anderson Power Pipe.

Like said above I would do gears 3.55-4.10, a good valve body, a shift kit, and maybe a stall converter, the AOD isnt the best performing trans, with that stuff you car will feel much faster.

Keep the stock cam in there, maybe swap in a set of 1.76 ratio roller rockers. I would do some suspension mods too.

You really have to ask yourself, what do i want outta this car. Is this car something that your always going to upgrading, i mean will you be getting a blower for anytime soon, things like that. You dont wanna buy parts twice, that sucks.

CAI is a waste of money, 150 bucks or so for 1-2 HP maybe!! Pulleys do help, but it killed my 2g alt. An intake will help and im a big fan of the Cobra/gt40 family. I made 495 rwhp with the Cobra intake and wanted to keep it but it became way to restrictive!

First thing id do is gears. I gained a full second in a stock 90 lx by switching to 4.10s from 2.73s.. 14.7 to a 13.7..

Yep, really need to go by the K.I.S.S. method here. I have done multiple budget Mustangs for myself and friends. I ran a 13.68@99 with just h-pipe, catback, and pulleys in a 88 LX 5spd (with slicks).

Stock air box w/ silencer removed is a FREE mod, and you can get a drop in K&N cheap. I have one if you want one PM me.

You have the exhaust done already so thats done with.

GEARS GEARS GEARS!!! Get some FRPP 3.73 (minumum with AOD IMHO) or 4.10 and it will feel like you added a supercharger. Like said above thats the best gain.

Valvebody should be high on the list too, it will add longevity to the tranny as well.

Cam and complete fuel system (pump,MAF,injectors,intake,pull the silencer add a filter) gears and a 5 speed.

Thats relatively cheap and it made my coupe pretty fast
my next step was a set of afr 185s.

I am pretty much in the same boat as Mac 55, I just bought a 92 convertible and I'm trying to figure out where to start with mods. I would like to know more about jrichkers suggestion to install a 87-88 Thunderbird Turbo Coupe rear end. My car came with a Ford 1126A five lug conversion. If I go with the T'bird rear end will I be able to use the five lug axles from my car, and which rotors would I use? Also, would this be a straight across swap as far as the installation, or would I have to fabricate or buy some other parts?This is a great thread and a big help to me. Thanks for all of the suggestions.

i'm starting to upgrade my 90 i just put in Heddman Long tubes (ebay) and Electric Fan happy with the results next is 4.10 rear gears and then i'mma start with the top end / finding 4cyl springs
iono exacty how much money u have but i don't make much so i have to go cheap