3.73 gears

cachethunder

Registered User
hi. i buy a set of 3.73 gears for my 93 SC, please tell me your experience with this gears, gas mileage??? aceleration gains is good? realy loose top speed?? thanks:)
 
hi. i buy a set of 3.73 gears for my 93 SC, please tell me your experience with this gears, gas mileage??? aceleration gains is good? realy loose top speed?? thanks:)


I have a 93 auto. Best seat of pants mod you can do short of installing an AR blower. Car feel like it lost 500 lbs, I dont know that it hurt my gas milage since most of the time I am running it hard. I think you will love how the car accelerates. I am not one of those guys seeing if I can run 140 MPH. I perfer to keep my license

Ken
 
i agree with ken, one of the best mods for the buck. he's right about the seat of the pants feel, i have them in both of my '94sc's and loving every minute of it.:D
 
What will top speed be with the 3.73 gears?

According to mathmatical formula, it'll be in the neighborhood of 170 mph...but that's 6,000 rpm and not figuring any friction into the equation. Top speed will be power limited because when you go that fast, it takes a lot of power. I don't know of too many SCs out there that have the power capable to overcome the wind resistance at those speeds.

I've been running 3.73s for over a year now and like them very much. I lost only a couple mpg at most, but picked up on the acceleration. My SC runs about 500 rpm higher than before when cruising, but I don't have a problem with that...
 
3.73's and exaust lol.

3.73's all the way used to be able to hit 130 in 4th with my old gearing.
now 5th gear is actually usable besides on the freeway :p
good luck on the install.
 
Boost Boi, you have 3.73's in a 5-speed? You're the 2nd SC I've heard of. Most 5-speeds go 3.27 and no steeper than 3.55 out back. Can you even use 1st gear with 3.73's?

The M5R2 5-speed trans has different internal gear ratio's than a Mustang T5/T45 so that's why we don't run 3.73's. 3.27's in a 5-speed SC I hear is about the same as 3.73 in a T5.

3.73 is a good gear for auto's. I want to put 4.10's in my auto but I don't know how to correct the speedometer.

I have 3.27's in my 5-speed and like the way it pulls.
 
Boost Boi, you have 3.73's in a 5-speed? You're the 2nd SC I've heard of. Most 5-speeds go 3.27 and no steeper than 3.55 out back. Can you even use 1st gear with 3.73's?

The M5R2 5-speed trans has different internal gear ratio's than a Mustang T5/T45 so that's why we don't run 3.73's. 3.27's in a 5-speed SC I hear is about the same as 3.73 in a T5.

3.73 is a good gear for auto's. I want to put 4.10's in my auto but I don't know how to correct the speedometer.

I have 3.27's in my 5-speed and like the way it pulls.


we have 4.10's in our 86 5.0 mustang T-5...first gear is still very useful...


about how much would it cost to do a gear swap.....? with 3.73's
 
Boost Boi, you have 3.73's in a 5-speed? You're the 2nd SC I've heard of. Most 5-speeds go 3.27 and no steeper than 3.55 out back. Can you even use 1st gear with 3.73's?

The M5R2 5-speed trans has different internal gear ratio's than a Mustang T5/T45 so that's why we don't run 3.73's. 3.27's in a 5-speed SC I hear is about the same as 3.73 in a T5.

3.73 is a good gear for auto's. I want to put 4.10's in my auto but I don't know how to correct the speedometer.

I have 3.27's in my 5-speed and like the way it pulls.

My buddy here in town has the stock M5R2 from an '89, and 3.73 gears, and his 1st gear is useless.
 
I will probably swap out my 3:73 gears for 4:10s this year. The 3:73 from a stock gear are like nite and day. Better low end better mid range. I have only had my car up to 100 mph. and that was at the track. Gas mileage whats that?:D I too need to keep my cdl in my pocket.
 
we have 4.10's in our 86 5.0 mustang T-5...first gear is still very useful...


about how much would it cost to do a gear swap.....? with 3.73's

Like I said the T5 has different internal gear ratio's so you can run higher gears in the rear than you can in a 5-speed M5R2 SC.

http://www.sccoa.com/forums/showthread.php?t=74113

It cost me around $500 for the gear swap not including gears. I took the car to the shop, they dropped the rear end, rebuilt the trac-lok, new bearings, installed and setup the gears, refilled the diff, reinstalled it.

I supplied the gears and the poly diff bushings.

It's MUCH cheaper if you pull the carrier out yourself and take it in. Most of my cost was labor for remove/reinstall.

When I do the gears in my 90 SC auto I'm going to pull the rear out myself and drop it off at the shop. Some shops won't mess with IRS because they don't know much about it. Once you have the "pig, pumpkin, whatever" out it's the same as any 8.8" Ford rear end. Instead of tubes and solid axles shafts we have cv style half shafts. Not that big of a deal but some places won't even bother unless you pull the diff yourself.
 
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I pulled the center section out and had the gears set up on mine. $90 to set up. So now I can do it all again. 4:10 here I go!:eek:
 
Not last time it didnt need it. I probably will have to this time around. I would like to find a center section with 4:10s already in. That way if its to much I can swap back to the #:73 really easy.
 
Not last time it didnt need it. I probably will have to this time around. I would like to find a center section with 4:10s already in. That way if its to much I can swap back to the #:73 really easy.

I have a iron center section with 4:10 gear with the F150 spring
and alternate clutch set-up,seals, All new parts were used except
pumpkin housing. It has been use and driven to the track once.
and driven on the street .When I bought it I was told it
had less that 500 total miles on it.

I bought it because the guy wanted to sell because it was to low gear
for street use.He was not a racer so he did not need this low on a gear.

I would make a swap pumpkin for pumpkin with you if you had a
close to new clutch plates with the heavier truck spring. But
since your clutch and spring are old ,I don't think it would be a
even deal for me. So how can we get together with a fair swap
deal for both of us?

Randy
 
You have my number give me a call. This rear endhas no problem with grip at all. Its a little whiney but tall gears always are.
 
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