Hey guys, I've got a 2012 Ford Mustang GT with the 6R80 transmission. The car has been a best of 7.74 @ 93 mph with a 1.83 60'....the car has BBK shorty headers, BBK off road X, Roush axle-back, cold air intake, Shaftmasters aluminum driveshaft and a tune. SVE 17x4 fronts with 185/55/17 M&H Racemasters and 15x10 with 275/50/15 (26") Mickey Thompson ET Street radial S/S ran at 18psi. I've been tossing around the idea of putting a gear in the car but was wondering if the cost was worth the reward? I'm wanting to go from 3.15 to 3.31...I feel that any more gear (3.55, 3.73, 4.10) would be entirely too much because of how steep first gear already is in these cars. I plan on leaving the 26's on the car. I have BMR tubular K member, LCA's, LCA relocation brackets, UCA and mount, adjustable pan hard bar and a CHE brace all on the way for the car. I plan on doing a Circle D 4C converter in the near future but as of right now I'm just building the car in waves. What is your guys opinion on doing the gear swap? Thanks for the help!
3.15 to 3.31?
- Thread starter 12IngotYote
- Start date
I forgot to add in the original post that I don't plan on going boost. Maybe nitrous, way on down the road.
IMO, Converter before any other modification in your case
A little more gear can make the car FEEL faster at light throttle applications and running around. It won't actually BE faster WOT but, it'll feel nicer everyday. Not really worth the cost of the swap to go from 15s to 31, though I think the car should have come with 31s factory bc it a is a little sloppy putting around on 15s.
Totally depends on your goals and what type of racing you want to do. In our X275 582ci nitrous radial car, we cut consistent 1.05-1.09 60' times at 3280 lbs with a 4.29 rear gear on a 1.66 1st gear TH400. That car makes around 1800 HP. People who say it won't be faster and will only "feel" are, well, uneducated. But understand that car is built for 1/8th mile. The setup would slightly change for 1/4. Like I said, it depends on your goals.
As of right now, a different converter is going to help you more than anything to get the 60' down. N/A it's just not making enough power to get that heavy car out of the hole much harder with that auto. I'd look into getting a set of Viking double adjustable rear shocks to get some more extension at the hit on those radials and have the ability to control the compression as it rolls out. And get rid of those S/S radials and get a set of 275 Pro's.
It needs mechanical advantage (gear) or different torque multiplication (converter). Orrrr more power. :beer:
As of right now, a different converter is going to help you more than anything to get the 60' down. N/A it's just not making enough power to get that heavy car out of the hole much harder with that auto. I'd look into getting a set of Viking double adjustable rear shocks to get some more extension at the hit on those radials and have the ability to control the compression as it rolls out. And get rid of those S/S radials and get a set of 275 Pro's.
It needs mechanical advantage (gear) or different torque multiplication (converter). Orrrr more power. :beer:
I don't take that kindly sir, I've been building and racing cars for over 30 years and my education has come the hard way. No shit you are going to want more gear in a car with a 1.66 first. You may not want more gear with a 4.17 first, like the 6R80 has. It's going to feel a little perkier on the road with a bit more gear (like I said) but the evidence is staggering that most gain very little to nothing from rear gear swaps on the 6R80 when going all out. The fastest 6R80 cars out there are on 3.15s or 3.31s.
My car has been its fastest time on 275/50 ET Street Radial S/S tires. Dead hooked with a 1.83 60'...wouldn't 60 better than a 1.9 with a 28" tall(275) tire. I guess that was way too tall of a tire for the stock 3.15 gear. Along with all the suspension parts I have ordered, I also have Viking shocks on the way.
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I say get the circle d converter 5c you will gain alot. I had a 4c in my car and with the viking shocks and other mods it dead hook on the street and the track. I had a friend with the same mods but a 5c and he would 60ft .1 faster then me.
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