**F/S GM Motorsports Race Transmissions for Corvettes**
06-18-2009, 02:23 PM
#1
Former Vendor
Thread Starter
Member Since: Aug 2005
Location: Lewisville TX
Posts: 16,898
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
**F/S GM Motorsports Race Transmissions for Corvettes**
Get them now guys!
I have two GM Motorsports transmissions left. These boxes have specific ratios only built for GM Motorsports.
These are not available any longer.
Originally designed around World Challenge racing they were built only for a limited time and available only to race teams. They have HD bearings, syncro's, larger shafts.
We have gone through both of these, including complete REM treatment. Full race prep includes inspection and/or replacement of all gears, sliders, and shafts. There is very little drive train loss with this transmission and RPM drops are shown below, which makes this a super close ratio gearbox.
Again, keep in mind these are no longer available from GM. When they are gone they are gone!!!
Ratio's are:
1st: 2.29 (2078 RPM Drop between 1st and 2nd)
2nd: 1.61 (1695 RPM Drop between 2nd and 3rd)
3rd: 1.22 (1262 RPM Drop between 3rd and 4th)
4th: 1.00 (1050 RPM Drop between 4th and 5th)
5th: 0.85
6th: N/A
The transmission was worth close to 1.5 seconds off our lap times at Mid-Ohio.
Call today, $4000 o.b.o. + shipping
MID-OHIO. Pole position, lead every lap, won the race with this transmission
I have two GM Motorsports transmissions left. These boxes have specific ratios only built for GM Motorsports.
These are not available any longer.
Originally designed around World Challenge racing they were built only for a limited time and available only to race teams. They have HD bearings, syncro's, larger shafts.
We have gone through both of these, including complete REM treatment. Full race prep includes inspection and/or replacement of all gears, sliders, and shafts. There is very little drive train loss with this transmission and RPM drops are shown below, which makes this a super close ratio gearbox.
Again, keep in mind these are no longer available from GM. When they are gone they are gone!!!
Ratio's are:
1st: 2.29 (2078 RPM Drop between 1st and 2nd)
2nd: 1.61 (1695 RPM Drop between 2nd and 3rd)
3rd: 1.22 (1262 RPM Drop between 3rd and 4th)
4th: 1.00 (1050 RPM Drop between 4th and 5th)
5th: 0.85
6th: N/A
The transmission was worth close to 1.5 seconds off our lap times at Mid-Ohio.
Call today, $4000 o.b.o. + shipping
MID-OHIO. Pole position, lead every lap, won the race with this transmission
06-18-2009, 02:35 PM
#3
Melting Slicks
Getting cheaper .....
As mentioned 1.5 seconds was gained with this upgrade, what rear gear and transmission were you using previously and what rear ratio were you using with the GM Motorsports box... Looks like 3.90-4.10 with the GM Motorsports box.
What were the rear tire diameter also ( I should get off my lazy hiny and do some research ) ????
trying to find the $$$$, kids, houses and race cars sure will drain the wallet ...
As mentioned 1.5 seconds was gained with this upgrade, what rear gear and transmission were you using previously and what rear ratio were you using with the GM Motorsports box... Looks like 3.90-4.10 with the GM Motorsports box.
What were the rear tire diameter also ( I should get off my lazy hiny and do some research ) ????
trying to find the $$$$, kids, houses and race cars sure will drain the wallet ...
Last edited by RAFTRACER; 06-18-2009 at 02:39 PM.
06-18-2009, 04:30 PM
#5
Former Vendor
depending on the track, most were 4.10, some longer tracks were 3.90. You could use a 3.90 with a Proxes RA1 335 Rear ( Diameter unknown, should be a loaded roll out of 82ish~) as long as you had a min of 7500 limiter.
06-18-2009, 04:32 PM
#7
Former Vendor
Thread Starter
Member Since: Aug 2005
Location: Lewisville TX
Posts: 16,898
Received 406 Likes
on
300 Posts
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
Getting cheaper .....
As mentioned 1.5 seconds was gained with this upgrade, what rear gear and transmission were you using previously and what rear ratio were you using with the GM Motorsports box... Looks like 3.90-4.10 with the GM Motorsports box.
What were the rear tire diameter also ( I should get off my lazy hiny and do some research ) ????
trying to find the $$$$, kids, houses and race cars sure will drain the wallet ...
As mentioned 1.5 seconds was gained with this upgrade, what rear gear and transmission were you using previously and what rear ratio were you using with the GM Motorsports box... Looks like 3.90-4.10 with the GM Motorsports box.
What were the rear tire diameter also ( I should get off my lazy hiny and do some research ) ????
trying to find the $$$$, kids, houses and race cars sure will drain the wallet ...
Rear tires are a 335-30-18 which I believe is a 25.8" tall tire?
06-18-2009, 04:35 PM
#8
Melting Slicks
Thanks Louis, those were the answers I was looking for ......M6 and 3.42 is pretty good @ MO, I need that 1.5 sec though......back to work to make the $$$$$.......
