Gear Change

Tnfastbk · Jun 24, 2012

Ok folks how much of a performance change will I get going from a 3.90 gear to a 3.73 or 3.50ish. My motor was built around the gear being 3.90. Just kicking around the ideal, not sure that I will see a great fall off from just spirited street driving. Maybe I would see it on the track but..................

RacerX · Jun 24, 2012

With enough torque down low, that's not enough gear change to see a big difference. Might drop your rpms about 200-300

caspianwendell · Jun 24, 2012

It will give you a little more top end but not enough to go through all the set up work for me...just my opinion

Jeff73Mach1 · Jun 24, 2012

3.50 would be noticible, to the point of being probably more of a change than you would be happy with. When I went from 4.11 to 3.50 it was a very different driving experience. from 4.11 to 3.91 was just enough to be an improvement without losing the flavor of the cars performance.3.73 s would drop rpms a bit, but I agree that it is barely worth it.

c9zx · Jun 24, 2012

Roy, What are you trying to get rid of or improve? MPG, Muffler drone, general ride comfort, or ...... You know the car well so any meaningful gear change will be noticed. Assuming a 27" tall tire, at 70 MPH, with 3.91:1 gear, 1:1 high gear, gives about 3410 RPM. With 3.73 about 3245 RPM. With 3.50 about 3050 RPM. With a .82 overdrive 5th gear and 3.91 gear about 2800RPM, with .68 overdrive and 3.91 gear about 2320 RPM. Chuck

Tnfastbk · Jun 24, 2012

Roy, What are you trying to get rid of or improve? MPG, Muffler drone, general ride comfort, or ...... You know the car well so any meaningful gear change will be noticed. Assuming a 27" tall tire, at 70 MPH, with 3.91:1 gear, 1:1 high gear, gives about 3410 RPM. With 3.73 about 3245 RPM. With 3.50 about 3050 RPM. With a .82 overdrive 5th gear and 3.91 gear about 2800RPM, with .68 overdrive and 3.91 gear about 2320 RPM. Chuck

I am changing my Detroit locker out so the gear change is not an issue as far as the work goes. Was looking for a little more traveling capabilities. MPG is not even a consideration with this car, it is what it is. Just curios what I would lose dropping to a 3.50 or 3.73

JimNiki · Jun 24, 2012

when I bought mine it had 4.11's. Sure it accelerated quick but I got sick of sitting in the slow lane and getting overtaken by granddad in his corolla while going for a Sunday cruise with the Mrs. I swapped over to 3.25. With an fmx and tall tyres, I needed to come down this much to make it an enjoyable cruiser. This was the compromise I had to make.

Don65Stang · Jun 24, 2012

My favorite gear is a 3.50 for a non-overdrive trans car. To me it is a nice blend of performance & highway friendliness.

What about adding a Gear Vendor overdrive setup?

Widowmaker00 · Jun 25, 2012

I think I would keep it where it's at, but then again, I tend to favor more performance oriented cars.

trainey · Jun 25, 2012

If you decide to change, I have an extra set of 3.50 gears, from Ford Motorsports.

marks73 · Jun 25, 2012

Unless you plan on being where the ABC helicopter is hovering overhead with the $200,000 check. 3:70 or 3:50 tend to be the best all around street/strip gear. IMHO

Tnfastbk · Jun 25, 2012

Unless you plan on being where the ABC helicopter is hovering overhead with the $200,000 check. 3:70 or 3:50 tend to be the best all around street/strip gear. IMHO

DO WHAT:huh::huh::huh: so you saying you dont need a set of 3.90 gears

c9zx · Jun 25, 2012

4.30:1 works also.

Go here http://www.camaros.net/forums/showthread.php?t=100779 then scroll down to post number 6. It is your answer. If only they were not made of unobtainium. Chuck

Or this. http://www.stangerssite.com/honeodrive.html

OR THIS! http://www.mustang50magazine.com/techarticles/m5lp_0309_viper_t56_transmission_package/viewall.html

Tnfastbk · Jun 25, 2012

4.30:1 works also.

Go here http://www.camaros.net/forums/showthread.php?t=100779 then scroll down to post number 6. It is your answer. If only they were not made of unobtainium. Chuck

Or this. http://www.stangerssite.com/honeodrive.html

OR THIS! http://www.mustang50magazine.com/techarticles/m5lp_0309_viper_t56_transmission_package/viewall.html

Thats all nice but not gonna happen. The car will one day get a 5/6 speed but for now just conteplating a gear change

Knoxferatu · Jun 25, 2012

Stick with 3.90's, but swap the toploader for a TKO.

1971mach1 · Jun 25, 2012

+1

Leave the rear alone and put in a TKO-600. You'll want the 3.90s back anyway as soon as you

put in a 5-speed, doesn't make any sense to swap it twice.

Jeff73Mach1 · Jun 25, 2012

I went to 3.50's, I went to a 5 speed, I went to 3.89 gear

If I were doing it again I would do it like I have it now. With my overdrive 70 mph is 2400 rpm 90 is about 3100 and when 4th tops out around 130 and I shift into 5th I start off at 4600 rpm or so and then I am right in the meat of my powerband. I can cruise the interstate in 5th and accelerate without downshifting and I can cruise through town with enough power to rarely use 1st or need to shift out of third. My mileage is . . . not great, but I can get 16-17mpg on the road and 12 around town. (I can get 9 if I try real hard lol)

Tnfastbk · Jun 25, 2012

I went to 3.50's, I went to a 5 speed, I went to 3.89 gear

If I were doing it again I would do it like I have it now. With my overdrive 70 mph is 2400 rpm 90 is about 3100 and when 4th tops out around 130 and I shift into 5th I start off at 4600 rpm or so and then I am right in the meat of my powerband. I can cruise the interstate in 5th and accelerate without downshifting and I can cruise through town with enough power to rarely use 1st or need to shift out of third. My mileage is . . . not great, but I can get 16-17mpg on the road and 12 around town. (I can get 9 if I try real hard lol)

Not great? Drive mine for a while lol

Go Time · Jun 25, 2012

4.30:1 works also.

Go here http://www.camaros.net/forums/showthread.php?t=100779 then scroll down to post number 6. It is your answer. If only they were not made of unobtainium. Chuck

Or this. http://www.stangerssite.com/honeodrive.html

OR THIS! http://www.mustang50magazine.com/techarticles/m5lp_0309_viper_t56_transmission_package/viewall.html

I will need to ask a man at my church the next time I see him if DANA has any of these lying around. He is retired but was an engineer in the R&D dept. Dana was a Big Time company here in the Fort Wayne /Northern indiana Area. If He can get me some any body interested in a set up like this

If I get them for free maybey "pay it forward" ::tease::

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