Which gears should I get with 20" wheels?

[REPCobra10]

I just put some 20" wheels with 315/35 and 275/35 tires, respectively, on my car and I want to swap out the gears in the rear end as well. Right now, I have the stock 3.31's. The 20's seemed to slow it down a bit compared to the stock 18's. I was thinking either 3.73's or 4.10's would be best because I'm looking for brute acceleration and am unconcerned with fuel economy. I've had experience with 3.73's before in other vehicles, but never any vehicles with 4.10's. So, which gear do you guys think would be best with the 20" wheels?

 

[Red Turtle]

I just put some 20" wheels with 315/35 and 275/35 tires, respectively, on my car and I want to swap out the gears in the rear end as well. Right now, I have the stock 3.31's. The 20's seemed to slow it down a bit compared to the stock 18's. I was thinking either 3.73's or 4.10's would be best because I'm looking for brute acceleration and am unconcerned with fuel economy. I've had experience with 3.73's before in other vehicles, but never any vehicles with 4.10's. So, which gear do you guys think would be best with the 20" wheels?

4.10's will be extremely short wiith the tranny gearing. I would go with 3.73's.

Now, pics of the combo.

 

[REPCobra10]

Yeah, I was kind of worried about that. I was just unsure if 3.73's were enough or not for 20" wheels. I do see others with the same wheel and tire size running 3.73's with no complaints, so perhaps that's the route I'll take. Anyways, with regard to pictures, I have no camera at the moment, but feel free to PM your cell if you'd like and I'll send a few that I have on my phone. Thanks for the input.

 

[Red Turtle]

Yeah, I was kind of worried about that. I was just unsure if 3.73's were enough or not for 20" wheels. I do see others with the same wheel and tire size running 3.73's with no complaints, so perhaps that's the route I'll take. Anyways, with regard to pictures, I have no camera at the moment, but feel free to PM your cell if you'd like and I'll send a few that I have on my phone. Thanks for the input.

Are the 20's extremely heavy, and I would imagine that they are close to the same overall height as the stock set up..?

 

[REPCobra10]

The 20's are the Steeda Spyder wheels with the black face and the machined lip. They definitely feel a little heavier than the stockers. Height wise, I'd say that they're close, but definitely a little taller.

 

[REPCobra10]

The wheels made a huge difference with the overall look of the car though. My car is lowered on Eibach Sportlines. I also have the GT/CS front valance with fogs, Saleen grille, GT500 rear diffuser, GT500 spoiler and 5% tint all the way around.

 

[Mach828]

I'd get 4.30s.

3.73s is a waste. At least get the 4.10s.

The new 5.0s like the high rpms anyways.

and "extremely short" with 4.10s hahahahahahaha someone fears the gear

 

[snkchmr 1]

Im doing 410s in mine soon. I also have 20s on the Nitto DRs & they are a bit tall.

 

[Bud]

The 20's are the Steeda Spyder wheels with the black face and the machined lip. They definitely feel a little heavier than the stockers. Height wise, I'd say that they're close, but definitely a little taller.

I'm running the exact same wheels and size tires (michelin pilot super sports) and compared to the stock 18's the new rear setup was 10lbs heavier each and the fronts were only 2lbs heavier each. Quite a bit heavier in the rear and the super sports are one of the lighter tires out there.

Stock height on the 18's was 27.2". 315/35/20's run about 28.7, so the added weight and big change in tire height hurts for sure. I'd throw some numbers around in a calc and see what ratio would get you close to where you were with the stock tires.

 

[Red Turtle]

I'd get 4.30s.

3.73s is a waste. At least get the 4.10s.

The new 5.0s like the high rpms anyways.

and "extremely short" with 4.10s hahahahahahaha someone fears the gear

oke: Have you driven a 11-12' with 3.73's? I am in third gear by 40mph as the tranny gearing is very short. My 3.73's as short as my old 05 with 4.10's. I am crossing the traps on the 7k limiter in 4th with my 3.73's.

4.10's would be like 4.56's in the pre 11' cars and that is just dumb unless you are tracking the car weekly.

 

[BlackMamba3]

4.10's would be like 4.56's in the pre 11' cars and that is just dumb unless you are tracking the car weekly.

This all day long.

 

[kingnut]

Surprised noone goes with 315/30/20 instead. They are so much closer to stock OD.

 

[stang8psi]

3.73 gear with a 28" tire, you'll still be able to go through the traps in 4th.

 

[Bud]

Surprised noone goes with 315/30/20 instead. They are so much closer to stock OD.

Only toyo makes that size and it is an R compound autocross type tire. Supposed to be awesome in the summer time but not so good in cold weather. I wish other companies made that size, it is perfect. Dunlop makes a 325/30/20 but it is 500+ a tire and I honestly don't think I could fit it without doing some cutting.

 

[Grabber2012]

Why not split the difference and get 3.90s?

 

[1Sick2Valve]

I love my 4.30s!

 

[grnenvy]

I'm running the Toyo R 888 315s on a 20x12 rim. It's an awesome tire alot like the Nitto drag radial. In the winter it needs a little run time to heat up.

 

[Roger Davis]

Read this guys real track times not guesses.

Track Results from Gear Swap: - Ford Mustang Forums : Corral.net Mustang Forum

 

[32ValveSymphony]

I've got 3.73s with the Roush 20's. No complaints. Nice compromise between acceleration and RPM.

 

[kingnut]

Only toyo makes that size and it is an R compound autocross type tire. Supposed to be awesome in the summer time but not so good in cold weather. I wish other companies made that size, it is perfect. Dunlop makes a 325/30/20 but it is 500+ a tire and I honestly don't think I could fit it without doing some cutting.

it sucks on toyo makes a tire in that size. ive seen a couple guys with 275/35/20 F and 315/30/20 rear. it looks awesome.