one last question: would any of u know how many '89 gt's, manual tranny, white, w/sunroof that ford made? i'm just curious how rare my car is

underdrive pulleys
remove intake silencer and K&N filter
off-road H-pipe or X-pipe (catalytic pipes cost more and flow less)
shorty headers (long tube headers better but shortys allow the stock
cataltic converters to be put back on if you have to do an emissions
test)
bump initial timing (free but requires premium fuel)
1.7:1 ratio roller rockers (plus new valve springs)
cat-back exhaust system
short belt to bypass air pump

These things will make the car noticeably faster and make it rev more
freely. If you plan to keep the car for any length of time, I prefer
stainless steel exhaust components. See my Magnaflow post in the Ford
Racing area for install details. Beyond the stuff listed above, an
aftermarket intake manifold/throttle body/EGR spacer/mass air meter
would be on the list but the cost adds up.

The air silencer is in the fender on the other side of the air filter
box. It's a football sized piece of plastic.

I think what daniel means about a K&N is to retain the airbox, and use a flat panel filter.

The problem with getting rid of the airbox completly and sticking a conical filter in its place is you are bringing hot air into the engine instead of cooler air.

Otherwise The only thing I would add to that list is Gears, 3.73 at the minimum, but I would start at 4.10 gears.

Those are really common mods and will definitely make your 5.0 more throttle responsive and faster! Grab a book, ask questions, and do the work yourself! It'll be that much more satisfying and make you prouder of your Mustang!

Just one word of caution. The faster you make your car go, the more necessary it is to beef up your braking. The stock braking is woefully underpowered already, in my opinion, and should be addressed immediately.

Also, get subframe connectors. Weld-in, not bolt-on ones. Otherwise with all the extra power and torque you'll be adding, especially if you do gears, you'll have a greater chance of tweeking your frame over time.

Have fun!

Stewart

Yes. Keep the air box that is located on the fender inside the
engine compartment but remove the silencer that is inside the
fender.

>The problem with getting rid of the airbox completly and sticking a
>conical filter in its place is you are bringing hot air into the
>engine instead of cooler air.

Yes.

>Otherwise The only thing I would add to that list is Gears, 3.73 at
>the minimum, but I would start at 4.10 gears.

I have the optional 3.08:1 gears and have resisted the urge to go
to anything steeper since I do a lot of highway driving. The nice
thing about all the modifications listed above, is that MPG is not
affected (maybe a bit improved) during cruise.

>Also, get subframe connectors. Weld-in, not bolt-on ones. Otherwise with
>all the extra power and torque you'll be adding, especially if you do
>gears, you'll have a greater chance of tweeking your frame over time.

I have welded-in subframe connectors, the Ford Motorsport convertible
chassis stiffening kit (even though my car is a hatchback), and a 4
point g-load brace. I've never gotten around to engine compartment brace
but all of the above are recommended. I believe the convertible
chassis stiffening kit is no longer in production.

>Just one word of caution. The faster you make your car go, the more
>necessary it is to beef up your braking. The stock braking is woefully
>underpowered already, in my opinion, and should be addressed immediately.

I've managed to get by with stock brakes wih good pads and stainless
braided pads. I've eaten a fair number of rotors though. I'm not
sure what year Mustang you have but in 1987 the rotor size was increased
to 11" from 10".

quote:

---

Originally posted by Daniel Jones:
I've managed to get by with stock brakes wih good pads and stainless
braided pads. I've eaten a fair number of rotors though. I'm not
sure what year Mustang you have but in 1987 the rotor size was increased
to 11" from 10".

Dan Jones

---

I've managed with stock front brakes as well, with the only difference being the rear drums upgraded to disk brakes. Any amount of heavy braking still produces a lot of fade in my '90 GT though. That's why I strongly suggested he upgrade his '89 as well.

quote:

---

Originally posted by Daniel Jones:
[BI have the optional 3.08:1 gears and have resisted the urge to go
to anything steeper since I do a lot of highway driving. The nice
thing about all the modifications listed above, is that MPG is not
affected (maybe a bit improved) during cruise.
Dan Jones[/B]

---

With the 5 speed I actually noticed an increase in fuel economy with the 3.73 gear ratio.

What most people do not realize is that just because the motor is not reving as high does not mean that it is running more efficiently.

With a 3.08 gear you will be revving around 1500 or 1600 rpm the motor is lugging at that rpm trying to pull your 3000 lb car along.

There is no logical reason to run a 3.08 gear in a 5 speed mustang.

I would do a little research into the gear issue (I have, the only ratio that I have not run between 2.73 and 4.10 was 3.27, and if I were able to find a set of 4.30's or 4.56's before the diff goes together I would try them.

Dont fear the gear, once you have tried them you will not know how you lived without them.

This is dependent upon a variety of factors including cam timing,
exhaust configuration, intake manifold selection, EFI or carb, etc.
I can believe 3.73's would yield good fuel economy around town but
a stock EFI intake/head/cam combo can take advantage of low RPM
on the highway for better fuel economy. I can pull 28 MPG if I
keep the revs and speed down to legal limits. Typically, on long
trips, I run 75-80 MPH and it drops to 24-26 MPG. Around town, I
get 20 MPG. A buddy installed a set of 3.73's in his stock '93
Mustang Cobra and his fuel economy dropped to 21-22 on the highway.

>What most people do not realize is that just because the motor
>is not reving as high does not mean that it is running more
>efficiently.

Steady state cruise fuel economy is a function of throttling losses,
friction, tuning, and aerodynamic drag, among other factors. For
best fuel economy, you want to minimize throttling losses. A steep
gear with long runner intake helps do that and is why Ford installed
2.73's as the stock ratio with 5 speeds. Given CAFE requirements,
if 3.73's increased highway mileage you can bet Ford would have
used them instead.

>With a 3.08 gear you will be revving around 1500 or 1600 rpm
>the motor is lugging at that rpm trying to pull your 3000 lb car
>along.

That assumes a lower cruise speed than I usually go. Even so,
with mild cam tuning, long runner intake, stock heads, the taller
gear will pull better fuel economy on the highway. This may change
if you run a cam with longer duration, bigger heads, shorter runner
intake, etc. BTW, theoretically, weight is not relevent to fuel
economy on flat terrain for constant speed. In the real world, it
does affect things when going up and down hills or accelerating but
fuel economy for an automobile is dominated by aerodynamic drag and
friction (including rolling resistance).

>There is no logical reason to run a 3.08 gear in a 5 speed mustang.

Reduced wear, noise, and fuel economy. An easy test to see if
the higher revs might bother you at cruise is to run around in
4th gear, instead of 5th.

>I would do a little research into the gear issue (I have, the only
>ratio that I have not run between 2.73 and 4.10 was 3.27, and if I
>were able to find a set of 4.30's or 4.56's before the diff goes
>together I would try them.

I have 5 cars with 5 speeds (the other is a 4 speed automatic).
I've run rear gears from 2.75:1 to 4.22:1 and what I like varys from
vehicle to vehicle. The Pantera has 4.22:1 and the Triumph 3.90:1
and I wish had taller gears in both (or beteer yet a 6 speed). The
'66 Mustang runs a 3.50:1 with a Tremec TKO. It would not be happy
with something in the 3.08:1 range because the cam/heads/and induction
all need some RPM to start working. It might like a steeper gear but
traction is already a problem in gears 1, 2, and 3. When I add the
Novi supercharger to the 5.0L, I expect a similar situation so I think
I'll keep the 3.08's.

I used to drive a 289 Mustang with 4:11 in the rear. I don't know what it did to the mileage because I never checked it. I wanted a performance gain and it was a great driving gear. Of course I never went on trips over 500 miles but I didn't have any problems with this set up at all. I drove the car set up this way for about 2 years and traded it in on another Mustang that ended up with 4:56. That was a little too steep for those long trips but it was a lot of fun to drive around town.

I don't really understand why so many people seem to be afraid of anything over a 4:00 to 1 ratio.

John Quinn

Gears are where it is at! It would/will be the next step I would take if I ever get a stang. Right behind the Flowmaster exhaust and silencer removal for the K$N filter :-D