4 or 5 speed
Cruising
Joined: Sep 2005
Posts: 12
Likes: 2
I'm sticking original 4 speed, but I avoid highways for another reason, below. If you want it highway friendly I totally agree, OD is a must.
That said, my 73 on the highway is a bumpfest
. I'm in CA and all the highways here are sections of cement with seams every (20?) feet or so. The car just gets hammered on the highway. I say this because if you are aiming for highway I suggest making sure your suspension / tires are highway friendly too, for me that's worse than the roughly 3k RPM @ 65 MPH.
That said, my 73 on the highway is a bumpfest
. I'm in CA and all the highways here are sections of cement with seams every (20?) feet or so. The car just gets hammered on the highway. I say this because if you are aiming for highway I suggest making sure your suspension / tires are highway friendly too, for me that's worse than the roughly 3k RPM @ 65 MPH.
Last edited by sparker1776; Sep 29, 2016 at 04:48 PM.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
When it comes to OD transmissions look at the OD gear ratio and you rear end ratio.
TKO 600 is sold with a .,82 or .64 OD choice. If you have 3.55 or less rearend the .82 is the wiser choice
TKO 600 is sold with a .,82 or .64 OD choice. If you have 3.55 or less rearend the .82 is the wiser choice
Advanced
Joined: Apr 2016
Posts: 92
Likes: 5
I have never heard of these before. Reading the website looks very interesting, and potentially useful. However the cost seems on par with just buying and installing a T56 or such. Anyone ever actually install and use one of these?
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I liked the TKO 5 speed so much I added another gear and went with a T56 6 Speed. Either one is a huge upgrade from the 4 speed. The 5 speed fits much easier.
The Gear Vendors OD is quite large and requires quite a bit of work to fit inside the tunnel.
The Gear Vendors OD is quite large and requires quite a bit of work to fit inside the tunnel.
Melting Slicks
Joined: Jul 2006
Posts: 2,285
Likes: 487
From: Salmon Arm, BC
No brainer....5 speed
It completely changes the driving experience if you drive on the freeway, and allows for normal conversation with your pax at speed.
Simply the best change I've made to my car yet.....
It completely changes the driving experience if you drive on the freeway, and allows for normal conversation with your pax at speed.
Simply the best change I've made to my car yet.....
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
Im in the middle of an engine and trans swap, and I mothballed my M20 for a brand new Richmond 5 speed OD.
I havent driven the car yet... heck there is no drivetrain in the car, but when there is, my 3.55's are going to feel like 2.73's in 5th. Regardless of any fuel economy gains, Im expecting to enjoy the car much more on the highway.
I havent driven the car yet... heck there is no drivetrain in the car, but when there is, my 3.55's are going to feel like 2.73's in 5th. Regardless of any fuel economy gains, Im expecting to enjoy the car much more on the highway.
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Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,152
Likes: 9,279
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
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Ive got 3.70 rear gears. Doing 75 for an hour is okay, trying to do 80 and I see the water temp creep up. I would prefer the 5 speed. Theres lots of long country roads around here but the long drives are accessed by the highways.
Instructor
Joined: Sep 2015
Posts: 216
Likes: 16
From: Haverfordwest Pembrokeshire
I spent a long time thinking about this one when I discovered I had a 4.56:1 rear which explained my engine screaming at anything over 55, at first the 5 speed TKO 600 was in the frame with a 3.55:1 rear end but totting it all up with shipping to UK and duties on arrival it just got too expensive.
I've bought the new diff already to swap this winter then I started having issues with the 4 speed but in the end I still stuck with it as conversion to M22w spec still comes in a lot less than the 5 speed, mines a weekend toy so I would never do enough miles to justify the expense and hopefully with the new diff highway driving will be a lot better.
Just my 2 pennuth!
Graham
I've bought the new diff already to swap this winter then I started having issues with the 4 speed but in the end I still stuck with it as conversion to M22w spec still comes in a lot less than the 5 speed, mines a weekend toy so I would never do enough miles to justify the expense and hopefully with the new diff highway driving will be a lot better.
Just my 2 pennuth!
Graham
Le Mans Master
Joined: Oct 2007
Posts: 7,444
Likes: 970
From: Tennessee/Rhode Island
5 speed all the way...I too basically use my 78 as a toy and weekend cruiser but would love a 5 speed instead of the 4 speed with 3.70 gears BUT cannot justify the outrageous prices for the conversion, doing it myself no less. If I could get it done for around $2,500-3,000, I probably would do it but it seems that the total all in cost is around $5K....just can't justify that money for an occasional use car....
Am I wrong about the do it yourself price? Is that $5K number seem about right for a TKO 5 speed with steep overdrive (.64) all in with all accessory parts like driveshaft, bellhousing, clutch, shifter, etc?
Am I wrong about the do it yourself price? Is that $5K number seem about right for a TKO 5 speed with steep overdrive (.64) all in with all accessory parts like driveshaft, bellhousing, clutch, shifter, etc?
Last edited by jb78L-82; Oct 3, 2016 at 09:39 AM.
Le Mans Master
Joined: Oct 2007
Posts: 7,444
Likes: 970
From: Tennessee/Rhode Island
Instructor
Joined: Sep 2015
Posts: 216
Likes: 16
From: Haverfordwest Pembrokeshire
5 speed all the way...I too basically use my 78 as a toy and weekend cruiser but would love a 5 speed instead of the 4 speed with 3.70 gears BUT cannot justify the outrageous prices for the conversion, doing it myself no less. If I could get it done for around $2,500-3,000, I probably would do it but it seems that the total all in cost is around $5K....just can't justify that money for an occasional use car....
Am I wrong about the do it yourself price? Is that $5K number seem about right for a TKO 5 speed with steep overdrive (.64) all in with all accessory parts like driveshaft, bellhousing, clutch, shifter, etc?
Am I wrong about the do it yourself price? Is that $5K number seem about right for a TKO 5 speed with steep overdrive (.64) all in with all accessory parts like driveshaft, bellhousing, clutch, shifter, etc?
Graham
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
At first glance, the TKO looks like a much more cost effective option, but it will nickel and dime you to the point that the price is just as much as the Richmond.
It is however possible to cut costs with the TKO and probably come out just above the 3K mark, but buying a stock TKO, cutting off the webbing underneath the tail, and fabricating your own offset onto the stock shifter.
You would still need 31 spline yoke with u joint straps, shorten driveshaft, speedo cable adapter, reverse light pigtail, and trans mount pad.
Or you could just get a Richmond and modify the trans mount pad and be done.
Melting Slicks
Joined: Jun 2011
Posts: 3,114
Likes: 597
5 speed all the way...I too basically use my 78 as a toy and weekend cruiser but would love a 5 speed instead of the 4 speed with 3.70 gears BUT cannot justify the outrageous prices for the conversion, doing it myself no less. If I could get it done for around $2,500-3,000, I probably would do it but it seems that the total all in cost is around $5K....just can't justify that money for an occasional use car....
Am I wrong about the do it yourself price? Is that $5K number seem about right for a TKO 5 speed with steep overdrive (.64) all in with all accessory parts like driveshaft, bellhousing, clutch, shifter, etc?
Am I wrong about the do it yourself price? Is that $5K number seem about right for a TKO 5 speed with steep overdrive (.64) all in with all accessory parts like driveshaft, bellhousing, clutch, shifter, etc?
If you cannot justify the cost wait until the current transmission needs a rebuild, then it is much easier to justify.
I would skip the 5 speed and look at 6 speed options.
Le Mans Master
Joined: Oct 2007
Posts: 7,444
Likes: 970
From: Tennessee/Rhode Island
Thanks everyone...I think the 6 speed requires more tunnel cutting than the 5 speed?
I agree about the TKO nickel and diming you to death with all the accessories. I look into this about 5 years ago and the marketing tactic is to have a reasonable entry price point and then $ option the crap out for all the add ons. The Richmond may be the way to go...I have not looked into it carefully...
I agree about the TKO nickel and diming you to death with all the accessories. I look into this about 5 years ago and the marketing tactic is to have a reasonable entry price point and then $ option the crap out for all the add ons. The Richmond may be the way to go...I have not looked into it carefully...
Instructor
Joined: Sep 2015
Posts: 122
Likes: 17
From: MA
My T56 magnum 6-speed conversion from TH350 auto came in around $6400 CDN ~ $4740 US. (everything to convert a auto to manual) Less if you start with a manual.
If you cannot justify the cost wait until the current transmission needs a rebuild, then it is much easier to justify.
I would skip the 5 speed and look at 6 speed options.
If you cannot justify the cost wait until the current transmission needs a rebuild, then it is much easier to justify.
I would skip the 5 speed and look at 6 speed options.
I have to ask out of curiosity and I mean no disrespect but when are you going to use 6th gear in a C3? Its so tall, I guess when your shifting from 5th as the speedo is flying past 140 mph? I just bought a 2016 Tacoma with a 6 speed and honestly I just don't get why they put that gear in there. On the highway in 6th, the cruise control has trouble because the truck is so far behind the power curve. I can see shorter ratios and keeping the power up with quicker shifts but seems like a gimmick to me. Not to mention the size of the T56 compared to the Tremec.