TKO-600/Rear Gear Combinations
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 34
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From: Willow Spring NC
TKO-600/Rear Gear Combinations
I'll soon be going with a Keisler 5-speed and also plan to have the rear end rebuilt, at which time I'll be able to select any gearing I choose. I currently have a 3.36 gear. I asked the Keisler rep and he suggested the TKO-600 and a 3.73 gear.
Who is out there running a TKO and what rear gears are you running? Impressions? Just looking for some more info to base a decision on.
Thanks in advance.
Who is out there running a TKO and what rear gears are you running? Impressions? Just looking for some more info to base a decision on.
Thanks in advance.
Pro
Joined: Apr 2000
Posts: 625
Likes: 0
From: The Villages FL
Rear Gears
If you remember Project Shark Attack from Corvette Fever Magazine over the past year and a half, we the rear was rebuilt 3.70's were put in, but most of us found that it made 1st gear too steep; red lined (6000rpm) at 30mph. We went back to the 3.36's that came with the car and things improved all around. There was more than ample torque available. 3.08's would certainly work, but the 3.36's seemed best in that application.
Spike
Spike
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 34
Likes: 1
From: Willow Spring NC
Originally Posted by Duke94
I have the TKO-600 with 3.70 gears, works great. Lots of low end torque plus will cruise at 70 MPH at about 1800-2000 RPM.
Melting Slicks
Joined: Oct 2001
Posts: 2,065
Likes: 1,395
From: Halifax, Nova Scotia, Canada
Originally Posted by Duke94
I have the TKO-600 with 3.70 gears, works great. Lots of low end torque plus will cruise at 70 MPH at about 1800-2000 RPM.
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Former Vendor
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From: knoxville tn
Gear ratio's
Hey Bob
If you have a 3.36 the TKO-500 is a good match.
The 3.27 gear will greatly improve your acceleration and give you plenty of o.d.
One of the things I always tell my customers is try what you have you can always go down in rear gear later.
We have a 65 vette with a Ramjet 350/380 hp 3.73 and the TKO-500
it really screams in 1st and it's a lot of fun. That would probably be to low for most.
Gene
If you have a 3.36 the TKO-500 is a good match.
The 3.27 gear will greatly improve your acceleration and give you plenty of o.d.
One of the things I always tell my customers is try what you have you can always go down in rear gear later.
We have a 65 vette with a Ramjet 350/380 hp 3.73 and the TKO-500
it really screams in 1st and it's a lot of fun. That would probably be to low for most.
Gene
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 34
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From: Willow Spring NC
Gene,
I had considered that, and without rebuilding the differential it's likely how I'd go. Since my differential has alot of play in it and is also leaking, I figured I'd look for the "ideal" combination, since it's easy enough to put any set of gears into it during the rebuild of the diff. To that end, I guess the real question is, "If you were replacing the differential and getting a TKO at the same time, which combination would you choose and why?".
A loaded question to be sure, but just looking for as much information as I can get to help me reach a decision.
Thanks for all the responses, keep them coming!
I had considered that, and without rebuilding the differential it's likely how I'd go. Since my differential has alot of play in it and is also leaking, I figured I'd look for the "ideal" combination, since it's easy enough to put any set of gears into it during the rebuild of the diff. To that end, I guess the real question is, "If you were replacing the differential and getting a TKO at the same time, which combination would you choose and why?".
A loaded question to be sure, but just looking for as much information as I can get to help me reach a decision.
Thanks for all the responses, keep them coming!
Intermediate
Joined: Oct 2006
Posts: 33
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From: FT. Worth Tx.
Originally Posted by C3Bob76
Gene,
I had considered that, and without rebuilding the differential it's likely how I'd go. Since my differential has alot of play in it and is also leaking, I figured I'd look for the "ideal" combination, since it's easy enough to put any set of gears into it during the rebuild of the diff. To that end, I guess the real question is, "If you were replacing the differential and getting a TKO at the same time, which combination would you choose and why?".
A loaded question to be sure, but just looking for as much information as I can get to help me reach a decision.
Thanks for all the responses, keep them coming!
I had considered that, and without rebuilding the differential it's likely how I'd go. Since my differential has alot of play in it and is also leaking, I figured I'd look for the "ideal" combination, since it's easy enough to put any set of gears into it during the rebuild of the diff. To that end, I guess the real question is, "If you were replacing the differential and getting a TKO at the same time, which combination would you choose and why?".
A loaded question to be sure, but just looking for as much information as I can get to help me reach a decision.
Thanks for all the responses, keep them coming!
This is a good set up if your HP is bellow 500.
Le Mans Master
Joined: Oct 2000
Posts: 8,897
Likes: 1,357
From: Santa Ana CA
Originally Posted by C3Bob76
Gene,
"since it's easy enough to put any set of gears into it during the rebuild of the diff."Thanks for all the responses, keep them coming!
"since it's easy enough to put any set of gears into it during the rebuild of the diff."Thanks for all the responses, keep them coming!
Not quite true as you are limited by the carrier. A 3-series carrier will accept standard GM Corvette gears up to 3.70 (maybe 3.90 from the aftermarket). (No such thing as a 3.73:1 from GM for C2-C3 Corvettes.) To move up to a 4:11 or higher, you would need to install a 4-series carrier, or possibly find something that could work from the aftermarket.
Not trying to be a smart azz, just in case you didn't know.
Last edited by toddalin; Nov 30, 2006 at 07:03 PM.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Originally Posted by toddalin
Not quite true as you are limited by the carrier. A 3-series carrier will accept standard GM Corvette gears up to 3.70 (maybe 3.90 from the aftermarket). To move up to a 4:11 or higher, you would need to install a 4-series carrier, or possibly find something that could work from the aftermarket.
Not trying to be a smart azz, just in case you didn't know.
Not trying to be a smart azz, just in case you didn't know.
I run a 3.70 gear in my TKO 500 and Ithink this is a great gear. My motor does not make a lot of low end power so driving at 65 at 1200 rpm would not fly. I cruise the highway at 2200 to 2300 at 70+ mph and it is very smooth. You have to consider what power band your motor has. The newer FI motors makes gobs of low end torque so they can cruise at 1200 rpm all day. If you are cammed for low end torque a 3.36 or 3.08 is OK. If you are cammed with considerable duration you need more gear.
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 34
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From: Willow Spring NC
Originally Posted by toddalin
Not quite true as you are limited by the carrier. A 3-series carrier will accept standard GM Corvette gears up to 3.70 (maybe 3.90 from the aftermarket). (No such thing as a 3.73:1 from GM for C2-C3 Corvettes.) To move up to a 4:11 or higher, you would need to install a 4-series carrier, or possibly find something that could work from the aftermarket.
Not trying to be a smart azz, just in case you didn't know.
Not trying to be a smart azz, just in case you didn't know.
Drifting
Joined: Aug 2003
Posts: 1,424
Likes: 0
From: Lakeland FL
I just got my TKO-600 and will be getting my diff back tomorrow. I had it rebuilt with 3.70 gears as Gene suggested. Sounds like it's a good way to go. The gears aren't cheap nor is the rebuild so I thought long and hard about it and chose the 3.70's.
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 34
Likes: 1
From: Willow Spring NC
Update
Just an update, I put a call in to Gene at Keisler today, ordered the TKO-600 (.64). I'm also looking at my options for having the differential rebuilt, including using forum member GTR1999. I liked what he had to say and I feel I couldn't do much better (if at all) with anyone else. If he does the rear end, I'll likely have him throw in 3.73's as it seems to me to be the best match for the new tranny, and it's what he said he'd be using instead of 3.70's.
Thanks for all the input, it was a big help!
Thanks for all the input, it was a big help!
Drifting
Joined: Jul 2003
Posts: 1,868
Likes: 294
From: West of Burlington, Ontario Canada
C3Bob76
I think the first thing to consider is where your motor likes to cruise. Once you know what the best torque range is and where you get the best fuel economy you would use a rpm calculator (found on ours and other sites) to pick an overdrive ratio that when combined with your tire size will put you at the rpm you want at the speed you want to cruise at. Fuel injected engines have a computerized management system that will allow lower rpm cruising without wasting fuel and loading up the engine so you can get away with cruising at 1200 rpm at 70 mph. Carburetors are not capable of runing at the wider ranges and stock or close to stock setups usually like it at about 1800 ish to 2300 rpm. Anything lower than that will waste fuel instead of saving it which besides lowering high engine rpm is why you have an OD tranny to begin with. Every engine is different and every driver has a different expectation of what he or she likes. Most people can usually tell what RPM their engine like to cruise. I would shoot for that rpm with your present rear gear and see first gear suits you. Not too low and not too high. You can always change the rear gears later. My first choice though would be 3.73's and the TKO 600 with a .64. 2150 RPM @ 70 mph with 26" tires.
I think the first thing to consider is where your motor likes to cruise. Once you know what the best torque range is and where you get the best fuel economy you would use a rpm calculator (found on ours and other sites) to pick an overdrive ratio that when combined with your tire size will put you at the rpm you want at the speed you want to cruise at. Fuel injected engines have a computerized management system that will allow lower rpm cruising without wasting fuel and loading up the engine so you can get away with cruising at 1200 rpm at 70 mph. Carburetors are not capable of runing at the wider ranges and stock or close to stock setups usually like it at about 1800 ish to 2300 rpm. Anything lower than that will waste fuel instead of saving it which besides lowering high engine rpm is why you have an OD tranny to begin with. Every engine is different and every driver has a different expectation of what he or she likes. Most people can usually tell what RPM their engine like to cruise. I would shoot for that rpm with your present rear gear and see first gear suits you. Not too low and not too high. You can always change the rear gears later. My first choice though would be 3.73's and the TKO 600 with a .64. 2150 RPM @ 70 mph with 26" tires.
Last edited by GMJim; Dec 12, 2006 at 07:57 PM.