I'm going with 3:55's because they came in autos and a bunch of Fords trucks, meaning they are easy to find and not to mention inexpensive since they are cosidered stock in some vehicles. RIght now I have a little too much top end power with my modifications and what I'd like to do is move the power a little sooner in the RPM range more like around 4k-5k and keep pulling. I've also heard with 3:73's you run out of gears really quick and first gear is insanely short which I don't really like the idea of. I've made my decision based on future mods. and professional opinions and most of them say go with 3:55's and if there is a need to go :73's later on then go for it but since I drive my mustang as a daily driver as well and on the high way that 3:55's would work out better for me right now.
i'm with u john, 80% of my driving is interstate hwy, i need a little more out of the hole but i don't wanna give up to much upstairs, i'm running 2.73 now. not to mention my parts dept gave me a 2001 cobra rear [irs] that ford didn't want back. [it was replaced under warrenty but nothing was wrong with it] free 3.55 gears, i'm still trying to find out if i can bolt the locker right in , and if it will accept the c-clips or i gotta change the ring over, it's going in a 89 gt. see ya
I'm on my third stang and have had 3.73s installed on each. The first was an 88GT 5-speed, Second a 94GT Auto, and the third a 95 5-speed. Since you have a pre 1994 car, you can't go wrong with 3.73s. There is still plenty off RPM at highway speed...unless you like to run 80 mph + all the time.
The 94 & 95 cars have a higher (numerically) first gear ratio in the trans that makes first gear really short with 3.73 and a five speed. But the look on your buddy's face when you slam the gas is worth the quick shift.
I have seen quite a few e-mails from people who purchased 3.55s and then wished they'd gone with 3.73. I have yet to read e-mail from someone with 3.73s that says, wished I gone with 3.55s.
multiply gear ratio by 336(constant) by mph divide the total by tire diameter
as you can see there is not much diff in rpm between 3.55s and 3.73s the advantage will be on acceleration thru the gears by 3.73s. the 4.10s are a liittle much unlees you have the engine for them or leaning more towards 1/4 mile or stoplight fun with stickies.
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[b]95 GT Now 331 TFS TW FoxLake stage 1 heads, TFS-2 cam, Track Heat Intake, 75mm TB, ProM80 MAF, 1-3/4" mac Long tubes full 3" mac exhaust rwhp 351.65 rwtq 370.71
95gt On stock engine 13.523@101.178mph 1.765 60ft 8.567 1/8th mile w/slicks
13.60@103.46mph 1.81 60ft w/slicks
Also had 87Gt carb'd 306 best time 11.48@119.98 N.A.
88 Ttop GT(rare)w/ lots of mods
[quote]Originally posted by maxxxxd
[b]4.10s were meant for "TRACK ONLY" cars or automatics that are geared differently than manual trans. cars.
4.10s ARE NOT TRACK ONLY GEARS ON STICKS YES THEY ARE MORE TRACK ORIENTED BUT WOULD MATCH THE POWER BAND FOR SETUPS WITH CAM/HEAD/INTAKE CHANGES SUCH AS A TFS SEPTUP TRACK HEAT COMBO WITH THE STAGE 2 CAM IN A SMALL CUBE 302 or u'd be out of the cams cruising rpm in 5th gear on the highway.
3.55s if you still want to drive instead of filling up at the gas station. 3.73s if you don't do much highway driving.
There IS ONLY A MINOR DIFFERENCE, but a DIFFERENCE nontheless.
Geeze,are you saying the 140 rpm diff between them will affect the gas milage that much.I really don't think so. the diff is in acceleration so with gears you'd just have to shift earlier cause the revs come up quicker when changing gears in the rear.
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[b]95 GT Now 331 TFS TW FoxLake stage 1 heads, TFS-2 cam, Track Heat Intake, 75mm TB, ProM80 MAF, 1-3/4" mac Long tubes full 3" mac exhaust rwhp 351.65 rwtq 370.71
95gt On stock engine 13.523@101.178mph 1.765 60ft 8.567 1/8th mile w/slicks
13.60@103.46mph 1.81 60ft w/slicks
Also had 87Gt carb'd 306 best time 11.48@119.98 N.A.
88 Ttop GT(rare)w/ lots of mods
i have an auto in my 91 lx and i just got 3.73's installed a couple days ago. the difference in acceleration was AWESOME. now i'm not yawning when i floor it. i get rubber in first and second now, and my car is basically stock. the freeway cruising is not even 300 rpm's more and i hardly drive on the freeway so i'm happy. but that's just me
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1991 LX 5.0: Eibach springs, Bilistein shocks/struts, Steeda lower control arms and strut tower brace, J&M subframe connectors, 3.73 gears, stock AOD, Flowmaster 2 chamber mufflers, underdrive pullys, bumped timing, white face gauges, nitto NT 450 tires on Pony rims.
I installed 3:55s yesterday and I am very happy with them. I get a little less traction but a ton better pickup and since I drive on the highway, the RPMS aren't really way up there. I'm very pleased with having 3:55s in my daily driver. If you don't drive your mustang on the highway or don't drive it very often I would go with 3:73s those aren't much different from 3:55s but I chose 3:55s simply because I drive my stang daily and I want traction and better acceleration without spending money on wider tires and bigger rims, it all equals out 3:55 and 3:73s I'm pretty sure theres not much of a difference when you go to the track to compare the two in the exact same car.
Originally posted by maxxxxd are you saying the 140 rpm diff between them will affect the gas milage that much.I really don't think so.
REALLY... Do you have evidence to back this up? Nope. I have personally tested these gears in a Fox Chassis Mustang with a T-5 5-speed transmission that came equipped with 3.08:1 gears, then installed 3.55:1 gears, followed by 3.73, then 4.10s. I don't have the numbers right in front of me, but there was a difference in mileage and performance. With 4.10s, the car would get out of the hole quicker, but would run out of steam at the top end. The 3.08s would launch slower, but had a lot more top end. It all depends on driving habits and where you plan on driving your car and what you have added to it (blower, turbo, nitrous, etc.). I performed the test for a project car for a major magazine and was religious about writing down everything, every step of the way, so others wouldn't waste money on parts they really didn't need. If you want to waste money, or have an inheritance to blow, go right ahead and try to drive your stock Mustang (w/ 5-spd.) on the freeway with 4.10 gears. You'll be hating life when you have to fill up more often and can't even keep up with 4-cylinder Mustangs with 2.73s... pretty lame.
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"Mad" Max
1992 LX, thanks to Chicane Sport Tuning and some friends.. it is now wrapped with new graphics and ready to hit the streets AGAIN!!!!
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