Doug Nash bought the rights to the T-10 and modified it to accept the OD unit.
Super T-10 for my C4?
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
t-10
why not just use the 4+3 without shifting the overdrive unit? The overdrive uses a sprague clutch that is good for 450 ft. Lbs of torque.
If you never shift the overdrive unit, it can't cause problems unless you break the Sprague. If you break the sprague, just buy another overdrive that doesn't shift!!! I am sure there are people that would think they are cheating you to sell you a non shifting overdrive for a couple hundred bucks.
If you never shift the overdrive unit, it can't cause problems unless you break the Sprague. If you break the sprague, just buy another overdrive that doesn't shift!!! I am sure there are people that would think they are cheating you to sell you a non shifting overdrive for a couple hundred bucks.
Thread Starter
Instructor
Joined: May 2007
Posts: 131
Likes: 0
From: Albuquerque New Mexico
USAsOnlyWay- I'm cool with making one. that is probably what I'm going to do, but if this guy answers you I would love to talk with him, thanks!
Update- I just found a Super T-10 that fits my specs as far as gear ratios, and I went ahead and ordered it. Looks like I'm definitely going to have to adapt it to my car now!
A T-5, T56, or 4+3, are not known to handle heavy abuse. I'm racing this car at a local road-course track, so I need something that will last and the T-10 appears to fit the bill. Plus it's lighter than the others.
-Rick-
Update- I just found a Super T-10 that fits my specs as far as gear ratios, and I went ahead and ordered it. Looks like I'm definitely going to have to adapt it to my car now!
A T-5, T56, or 4+3, are not known to handle heavy abuse. I'm racing this car at a local road-course track, so I need something that will last and the T-10 appears to fit the bill. Plus it's lighter than the others.
-Rick-
Thread Starter
Instructor
Joined: May 2007
Posts: 131
Likes: 0
From: Albuquerque New Mexico
I'm quite aware of that, but the 4+3 tranny breaks where it goes into the overdrive very often. (There's a spring loaded coupler that can't take much abuse)
The way it's designed, you cannot remove the overdrive parts and drive it.
The way it's designed, you cannot remove the overdrive parts and drive it.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
There are upgraded parts for that portion of the mainshaft. Have you talked to these people about how to strengthen the mainshaft and to see what sort of heavy-duty parts are available??
There is some good reading here.
While it sounds like you have a plan worked out, leaving the 4+3 in the car does solve a number of fabrication issues.
As coupeguy2001 said, don't use the OD unit. You can easily disconnect the wires to the solenoids and it will not shift into OD.
The 4+3 was used behind the Callaway Twin Turbo motors in the 87 and 88 C4 RPO . The 87 T-T car had 345Hp and 465 ft-lbs of torque. The 88 had even more HP and torque with the 4+3 still behind it.
In '88, there were 56 special Corvettes made for the SCCA Corvette Challenge Series. These cars used the 4+3 and L98 motors built especially for this road race series.
There is some good reading here.
While it sounds like you have a plan worked out, leaving the 4+3 in the car does solve a number of fabrication issues.
As coupeguy2001 said, don't use the OD unit. You can easily disconnect the wires to the solenoids and it will not shift into OD.
The 4+3 was used behind the Callaway Twin Turbo motors in the 87 and 88 C4 RPO . The 87 T-T car had 345Hp and 465 ft-lbs of torque. The 88 had even more HP and torque with the 4+3 still behind it.
In '88, there were 56 special Corvettes made for the SCCA Corvette Challenge Series. These cars used the 4+3 and L98 motors built especially for this road race series.
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
A T-56 will certainly handle the abuse. I won't argue that a T-10 isn't stronger and lighter, but plenty of T-56's have seen plenty of abuse. Most f-body T-56's are rated at 450 ft/lbs.
Either way, good luck with the swap. I'm curious to see how it comes out, and wonder if this would help those of us who dream about a Jerico in a C4.
Either way, good luck with the swap. I'm curious to see how it comes out, and wonder if this would help those of us who dream about a Jerico in a C4.
Thread Starter
Instructor
Joined: May 2007
Posts: 131
Likes: 0
From: Albuquerque New Mexico
Mojave-I'm with you there, I looked up a Jerico a while back, that would the the way! But, $$$$$
c4cruiser- I'm not sure, in fact as I look, I didn't tell you guys that I have an auto tranny now. (700r4) Thanks though-
-Rick-
c4cruiser- I'm not sure, in fact as I look, I didn't tell you guys that I have an auto tranny now. (700r4) Thanks though-
-Rick-
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
So what T-10 did you order, do you know the length of it compared to the 4+3 tranny. I know your auto drive shaft is shorter, as is the C-beam I believe. (Not sure on that though.) I do understand if you are doing the swap, wanting to be able to run the plain T-10 if you have no need for the overdrives and I have to believe a straight T-10 is lighter than a 4+3...right?
Keep us updated on the progress with pics and posts. I'd like to see it come along. Also, what gear ratios did you end up with?
Keep us updated on the progress with pics and posts. I'd like to see it come along. Also, what gear ratios did you end up with?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Instructor
Joined: May 2007
Posts: 131
Likes: 0
From: Albuquerque New Mexico
I got a BW Super T-10 with 2 cuts in the front gear meaning that it has:
2.43
1.34
1.13
1.00
Yeah, the T-10 weighs only 70 lbs!
I'll try to keep posting as I go thanks-
2.43
1.34
1.13
1.00
Yeah, the T-10 weighs only 70 lbs!
I'll try to keep posting as I go thanks-
