Tremec transimmion
Thread Starter
Intermediate
Joined: Sep 2018
Posts: 36
Likes: 0
From: Venice - Italy
Tremec transimmion
Hello everybody!
I write from Italy.
I'm going to install a Tremec gearbox on my '69 Corvette; actually I have the original manual M20 4 speed and I'd like to mount a 5 or 6 speed gearbox.
I found that the most common modify is with Tremec gearbox. Initially I opted for the 5 speed (Tremec TKO600) because I just look for a relax 5 gear for long travels; now I'm considering also the Magnum with 6 speeds...
Any suggestions?
I saw that it's possible to install TKO600 without cut or drill, just using conversion kit; do you know if this is possible also with the Magnum?
Thanks a lot for your help
PS; I'm sorry for my english...
I write from Italy.
I'm going to install a Tremec gearbox on my '69 Corvette; actually I have the original manual M20 4 speed and I'd like to mount a 5 or 6 speed gearbox.
I found that the most common modify is with Tremec gearbox. Initially I opted for the 5 speed (Tremec TKO600) because I just look for a relax 5 gear for long travels; now I'm considering also the Magnum with 6 speeds...
Any suggestions?
I saw that it's possible to install TKO600 without cut or drill, just using conversion kit; do you know if this is possible also with the Magnum?
Thanks a lot for your help
PS; I'm sorry for my english...
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I brought a 6 speed vette and the double over drive ZF transmission was so hopelessly over geared that it didn't have the power accelerate in 6th gear. It could actually go faster in 5th gear. I think that it came with a 3.43 rear end and I changed it to a 4.10 and it ran so much better
I installed the tko 600 in my 79 vette also with 4.11 rear end and it has the ability to cruise very nice at 200 Kph
I installed the tko 600 in my 79 vette also with 4.11 rear end and it has the ability to cruise very nice at 200 Kph
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I convertedmy 79 vette auto tranny to the 600. I had to cut the sheet metal under the console to fit the shifter block. Minor modification from a 4 speed car it is probably nothing unless the shifter is physically in a different place
the kits can come with a different cross member. Bolt on type. The mounting point of the tail shaft was different than my auto tranny. If you have a solid cross member it would be great to take it out
Burning Brakes
Joined: May 2017
Posts: 774
Likes: 375
From: Seattle WA
Hello everybody!
I write from Italy.
I'm going to install a Tremec gearbox on my '69 Corvette; actually I have the original manual M20 4 speed and I'd like to mount a 5 or 6 speed gearbox.
I found that the most common modify is with Tremec gearbox. Initially I opted for the 5 speed (Tremec TKO600) because I just look for a relax 5 gear for long travels; now I'm considering also the Magnum with 6 speeds...
Any suggestions?
I saw that it's possible to install TKO600 without cut or drill, just using conversion kit; do you know if this is possible also with the Magnum?
Thanks a lot for your help
PS; I'm sorry for my english...
I write from Italy.
I'm going to install a Tremec gearbox on my '69 Corvette; actually I have the original manual M20 4 speed and I'd like to mount a 5 or 6 speed gearbox.
I found that the most common modify is with Tremec gearbox. Initially I opted for the 5 speed (Tremec TKO600) because I just look for a relax 5 gear for long travels; now I'm considering also the Magnum with 6 speeds...
Any suggestions?
I saw that it's possible to install TKO600 without cut or drill, just using conversion kit; do you know if this is possible also with the Magnum?
Thanks a lot for your help
PS; I'm sorry for my english...
I have the TKO600 and love it.
The 5th gear ration (0.56) is like an overdrive and on the highway it is awesome to cruise easy at 80mph.
No cutting necessary. I used the perfect fit from Silver Sport Transmission.
https://shiftsst.com/articles/cat/ge...erfectfit-kit/
Melting Slicks
Joined: Jun 2011
Posts: 3,114
Likes: 598
Hello everybody!
I write from Italy.
I'm going to install a Tremec gearbox on my '69 Corvette; actually I have the original manual M20 4 speed and I'd like to mount a 5 or 6 speed gearbox.
I found that the most common modify is with Tremec gearbox. Initially I opted for the 5 speed (Tremec TKO600) because I just look for a relax 5 gear for long travels; now I'm considering also the Magnum with 6 speeds...
Any suggestions?
I saw that it's possible to install TKO600 without cut or drill, just using conversion kit; do you know if this is possible also with the Magnum?
Thanks a lot for your help
PS; I'm sorry for my english...
I write from Italy.
I'm going to install a Tremec gearbox on my '69 Corvette; actually I have the original manual M20 4 speed and I'd like to mount a 5 or 6 speed gearbox.
I found that the most common modify is with Tremec gearbox. Initially I opted for the 5 speed (Tremec TKO600) because I just look for a relax 5 gear for long travels; now I'm considering also the Magnum with 6 speeds...
Any suggestions?
I saw that it's possible to install TKO600 without cut or drill, just using conversion kit; do you know if this is possible also with the Magnum?
Thanks a lot for your help
PS; I'm sorry for my english...
https://www.corvetteforum.com/forums...-corvette.html
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I installed a 5 speed Tremec in mine years ago. I did make the cross member removeable at the time. No other mods were needed and everything bolted up fine. Later iput in a T56 and the fit was a lot more work. The crossmember had to be heavily modified. The shifter came up In the wrong location so I modded the console. I have seen others that have modded a shift lever so it comes up in the stock location.
Since this I have done over a dozen swaps from automatics to 5 speeds and 4 speeds to 5 speeds. The auto cars are easier due to a removeable crossmember. No mods are needed as the yprovide a bracket that bolts to the stock member. The 4 speed to 5 speed cars are ok to do without a removeable crossmember but the fit is real tight and takes some time and patience. Plenty of overdrive with the TKO. The install is easier with the TKO than the 6 speed.
Since this I have done over a dozen swaps from automatics to 5 speeds and 4 speeds to 5 speeds. The auto cars are easier due to a removeable crossmember. No mods are needed as the yprovide a bracket that bolts to the stock member. The 4 speed to 5 speed cars are ok to do without a removeable crossmember but the fit is real tight and takes some time and patience. Plenty of overdrive with the TKO. The install is easier with the TKO than the 6 speed.
Race Director
Joined: Mar 2016
Posts: 14,343
Likes: 8,153
From: Napa Valley California
I'm getting ready to order my auto to manual kit from Silver Sport Transmissions.
Their kits come with everything you need and no cutting.
Their prices do seem a bit high but when I started trying to pull all the parts needed from different vendors I found the SST kits were actually cheaper.
I looked into other kits as well and even though their advertised prices were less, by the time you added everything needed to their "base kits" the prices were equal to or in some cases more than SST.
Their kits come with everything you need and no cutting.
Their prices do seem a bit high but when I started trying to pull all the parts needed from different vendors I found the SST kits were actually cheaper.
I looked into other kits as well and even though their advertised prices were less, by the time you added everything needed to their "base kits" the prices were equal to or in some cases more than SST.
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Burning Brakes
Joined: May 2017
Posts: 774
Likes: 375
From: Seattle WA
I'm getting ready to order my auto to manual kit from Silver Sport Transmissions.
Their kits come with everything you need and no cutting.
Their prices do seem a bit high but when I started trying to pull all the parts needed from different vendors I found the SST kits were actually cheaper.
I looked into other kits as well and even though their advertised prices were less, by the time you added everything needed to their "base kits" the prices were equal to or in some cases more than SST.
Their kits come with everything you need and no cutting.
Their prices do seem a bit high but when I started trying to pull all the parts needed from different vendors I found the SST kits were actually cheaper.
I looked into other kits as well and even though their advertised prices were less, by the time you added everything needed to their "base kits" the prices were equal to or in some cases more than SST.
They are super cool too and will help you with choices for flex plate, clutch, etc if you need it.
Melting Slicks
Joined: Dec 2009
Posts: 3,229
Likes: 656
From: Thunder Bay
I have a TKO 600 in my '79. I converted the car from an automatic which meant some relatively minor modification of the floor. The swap is well worth it. I love the way it drives now. I did not use a kit. I put all the parts together myself over the course of about a year. I figure I might have saved $100, if that.
Drifting
Joined: Aug 2015
Posts: 1,939
Likes: 477
From: NSW, Australia
C3 of Year Finalist (track prepared) 2019
The tko kits from the vendors come with a special shifter and require no cutting, or you can do as I did and some of the others above and use the standard box and open up the hole in the floor a little to suit. I cut and welded an offset in the shifter stub so that it comes through the console like stock, and covered the opening in the floor under the console with a larger rubber boot. I used the factory Corvette bellhousing and z bar clutch release (after repairing all the pivots) and it works great. I didn't modify the crossmember at all.
The 6 speed requires some cutting, and from memory you cannot reuse your factory bellhousing and clutch release arrangement, adding cost and complexity to the conversion. I don't personally see the need for the additional gear. All depends on personal preference!
The 6 speed requires some cutting, and from memory you cannot reuse your factory bellhousing and clutch release arrangement, adding cost and complexity to the conversion. I don't personally see the need for the additional gear. All depends on personal preference!
Pro
Joined: Oct 2009
Posts: 664
Likes: 89
From: Marysville Ohio
Automatic cars require cutting (as drwet said). The auto shifter doesn't go through the floor like a manual. Cars that were originally manual should not need cutting if you get the right shifter setup.
I also converted a 79 from automatic to a TKO 600 - I love it. I am running a 3.73:1 rear end. I probably would not run less than a 3.55:1 ratio rear with a TKO, but really rear gearing just depends on the RPM range where your car makes power. Just try to make sure you think about that aspect of the conversion.
I also converted a 79 from automatic to a TKO 600 - I love it. I am running a 3.73:1 rear end. I probably would not run less than a 3.55:1 ratio rear with a TKO, but really rear gearing just depends on the RPM range where your car makes power. Just try to make sure you think about that aspect of the conversion.
Last edited by cooper9811; Sep 21, 2018 at 09:22 AM.
Instructor
Joined: Apr 2006
Posts: 108
Likes: 22
From: Duvall WA
Hello Mastfel74
Like "drwet" above I completed a TKO project buying part by part.
I would recommend buying a kit - especially if I lived in Italy.
My project started as a 1978 automatic with a 3:08 axel ratio.
I purchased the TKO-500 (3:27 1st gear ratio)
A vehicle is easier to drive and easier on the clutch if the axel ratio X 1st gear ratio = 10 +/-
A TKO-500 --- 3:08 X 3:27 = 10.0716 (Good combination)
A TKO-600 ---2.87 X 3:55 = 10.1885. (Good combination)
The single overdrive gear ratio of a TKO is enough overdrive for most older cars.
If the two overdrive gear ratios of a T56 six-speed are to be efficient especially at cruise speeds in 6th gear, many times EFI, a minimum of a 3:55 Axel gear ratio and a smooth running camshaft at engine speed of less than 1800 RPM are required.
A 350 engine with a modifications, and a 3:08 Axel ratio is very happy with a TKO-500.
Like "drwet" above I completed a TKO project buying part by part.
I would recommend buying a kit - especially if I lived in Italy.
My project started as a 1978 automatic with a 3:08 axel ratio.
I purchased the TKO-500 (3:27 1st gear ratio)
A vehicle is easier to drive and easier on the clutch if the axel ratio X 1st gear ratio = 10 +/-
A TKO-500 --- 3:08 X 3:27 = 10.0716 (Good combination)
A TKO-600 ---2.87 X 3:55 = 10.1885. (Good combination)
The single overdrive gear ratio of a TKO is enough overdrive for most older cars.
If the two overdrive gear ratios of a T56 six-speed are to be efficient especially at cruise speeds in 6th gear, many times EFI, a minimum of a 3:55 Axel gear ratio and a smooth running camshaft at engine speed of less than 1800 RPM are required.
A 350 engine with a modifications, and a 3:08 Axel ratio is very happy with a TKO-500.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Automatic cars require cutting (as drwet said). The auto shifter doesn't go through the floor like a manual. Cars that were originally manual should not need cutting if you get the right shifter setup.
I also converted a 79 from automatic to a TKO 600 - I love it. I am running a 3.73:1 rear end. I probably would not run less than a 3.55:1 ratio rear with a TKO, but really rear gearing just depends on the RPM range where your car makes power. Just try to make sure you think about that aspect of the conversion.
I also converted a 79 from automatic to a TKO 600 - I love it. I am running a 3.73:1 rear end. I probably would not run less than a 3.55:1 ratio rear with a TKO, but really rear gearing just depends on the RPM range where your car makes power. Just try to make sure you think about that aspect of the conversion.
Burning Brakes
Joined: May 2017
Posts: 774
Likes: 375
From: Seattle WA
The tko kits from the vendors come with a special shifter and require no cutting, or you can do as I did and some of the others above and use the standard box and open up the hole in the floor a little to suit. I cut and welded an offset in the shifter stub so that it comes through the console like stock, and covered the opening in the floor under the console with a larger rubber boot. I used the factory Corvette bellhousing and z bar clutch release (after repairing all the pivots) and it works great. I didn't modify the crossmember at all.
The 6 speed requires some cutting, and from memory you cannot reuse your factory bellhousing and clutch release arrangement, adding cost and complexity to the conversion. I don't personally see the need for the additional gear. All depends on personal preference!
The 6 speed requires some cutting, and from memory you cannot reuse your factory bellhousing and clutch release arrangement, adding cost and complexity to the conversion. I don't personally see the need for the additional gear. All depends on personal preference!
It is important to note that the TKO600 mirrors the Muncie gear ratios (at least very closely if not exactly) for 1-4. 5th is 0.56 I believe so it is like a massive overdrive. I already don't use 5th on regular streets usually. Just the highway.
Thread Starter
Intermediate
Joined: Sep 2018
Posts: 36
Likes: 0
From: Venice - Italy
Thanks to everybody for answers and for share experiences. I thought about the 6 spees just for more sport driving 'cause there is a big jump from 4th to 5th with 0.64. But considering:
1. I don't want to cut anything
2. At least my first need is to reduce rpm in highway
3. I have the 427 and quite short final ratio (3.70)
I'll buy the TKO 600 with 0.64 5th gear. and of course the complete conversion kit.
Thank again!
1. I don't want to cut anything
2. At least my first need is to reduce rpm in highway
3. I have the 427 and quite short final ratio (3.70)
I'll buy the TKO 600 with 0.64 5th gear. and of course the complete conversion kit.
Thank again!
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
I wish I had a gear between 4th and 5th in my car - kinda wish I'd done T56 since I had to cut the floor anyway. But not your problem...
On 45->60mph the 5th (0.64) is a bit low and then I have to downshift. 4th is a bit high. I'm running 3.70s. But I'm already into this transmission and am not about to dump the cash in for a T56.
On 45->60mph the 5th (0.64) is a bit low and then I have to downshift. 4th is a bit high. I'm running 3.70s. But I'm already into this transmission and am not about to dump the cash in for a T56.