Which TKO 600?
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Pro
Joined: Jun 2002
Posts: 538
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From: Johnsonville Wi
Which TKO 600?
I'm planning to put in a TKO 600. It looks like the RR version drops highway rpm more then I might like. The car is a 64 with a good tourqey motor and 3:36 gears. Right now I do 3,000 rpm @ 70 and the RR drops that to about 1750 while the straight 600 is about 2300. What do you guys have and are you happy with your model choice or would go to other O.D. ratio if you were doing it again?
Daffy
Daffy
Drifting
Joined: Feb 2005
Posts: 1,798
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From: Southeastern VA
Daffy,
I think you have the two boxes confused...The road race box has a .82 overdrive which keeps the rpm's up a little bit over the standard .64 box (2500 rpm will get you 74mph with .82). Keep in mind that while you feel you have a motor with good bottom end, when your in high gear and pull any kind of incline or want to throttle up, the engine is not at a good power making rpm and may struggle. I had the .64 box in my 69 Z/28 with a 600 hp motor and 560 lbft trq stroker and 4.10's and HATED it. The spread between 4th and 5th is too big in my opinion and limits your use of OD unless your speed is greater than 65 mph. Just my .02, I used a T56 in my current project.
I think you have the two boxes confused...The road race box has a .82 overdrive which keeps the rpm's up a little bit over the standard .64 box (2500 rpm will get you 74mph with .82). Keep in mind that while you feel you have a motor with good bottom end, when your in high gear and pull any kind of incline or want to throttle up, the engine is not at a good power making rpm and may struggle. I had the .64 box in my 69 Z/28 with a 600 hp motor and 560 lbft trq stroker and 4.10's and HATED it. The spread between 4th and 5th is too big in my opinion and limits your use of OD unless your speed is greater than 65 mph. Just my .02, I used a T56 in my current project.
Le Mans Master
Joined: Mar 2005
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From: Rocklin California
I have the .64 OD Tremec TKO 600 with 3.55 rear gears. 2000RPM at 70 MPH. 1st is a little lower then the M21, 2nd, 3rd, 4th about the same. 5th is a big drop which I kind of like since I have loud side pipes. You could go with the .82 5th and still probably do 70MPH at about 2500rpm. I rarely use 5th gear unless on the freeway of course. So you have the best of both worlds. But you will like the lower 1st gear with your rear end. Will get you rolling a little easier. 
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When you get ready to pull the trigger....give me a shout.I am knocking off 150.00 on top of my already low pricing for 3 forum members,or more that do a group purchase,and there are a couple guys in the C3 section ready to go...
Burning Brakes
Joined: Aug 2007
Posts: 814
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From: toronto ontario
Tko 500
I have a 65 with a 365 hp, 3.55 gears I installed a 500 a couple of years ago. The only problem that I have is the ratio in 1 st. you must shift to 2nd within a very short distance. If I had gone with the 600, I've been told the travel distance would have increased. I am very happy with the O.D. highway travel and r.p.m rates are great and it did quiet down the side exhust while in 5th.
Le Mans Master
Joined: Oct 2000
Posts: 8,897
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From: Santa Ana CA
I've got a 3.70:1 rear and the 0.64 OD and while it's nice on the freeway, there is a heck of a drop between 4-5. (Would love something around 0.75 OD.) With your rear, I'd go with the 0.82 OD.
...But then, with your rear end gears, I probably would have left the 4-speed.
...But then, with your rear end gears, I probably would have left the 4-speed.
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Le Mans Master
Joined: Feb 2008
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From: Toronto Ontario
I have a 65 with a 365 hp, 3.55 gears I installed a 500 a couple of years ago. The only problem that I have is the ratio in 1 st. you must shift to 2nd within a very short distance. If I had gone with the 600, I've been told the travel distance would have increased. I am very happy with the O.D. highway travel and r.p.m rates are great and it did quiet down the side exhust while in 5th.
Wayne, I just had the TKO600 installed in my 63 out at Stingray Auto Tech in Mississauga. When I originally called them, it was my intent to put in the TKO500 but Brian, the owner, cautioned me that with my 3.70 gears, 1st gear would be crazy-low. On his advice, I went for the 600. Can't wait for the snow to clear to try it out!
- Pat
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Joined: Dec 2007
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From: Point Of Rocks MD
Found this discussion very useful since I'm about at the point of ordering a Tremec. Like others here, trying to decide between the 500, 600, and 600RR. I've got a 63 convertible with a 355 hp ZZ4 engine. The 3.36 rear needs to be rebuilt, so I've pretty much got my choice of rear end ratio.
Any thoughts on what rear ends work best for each of the Tremecs? Or, has anybody got a combination they really like? I'm running rpm/speed and shift point calculators but with 3 transmissions and a bunch of rear ends, its a ton of data to try to make sense of.
Any thoughts on what rear ends work best for each of the Tremecs? Or, has anybody got a combination they really like? I'm running rpm/speed and shift point calculators but with 3 transmissions and a bunch of rear ends, its a ton of data to try to make sense of.
Drifting
Joined: Dec 2002
Posts: 1,946
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From: Long Beach CA
I put the 600 not in a Corvette, but my '71 Camaro. It has a 3.42 rear gear. First gear is great, bunches better than the 2.20 in the close ratio Muncie that was in it. The .64 overdrive is a hair too high for this combination. Freeway speeds are around 1,800-2,000 rpm. It'd be better with a higher rear end -- 3.55, 3.70 or higher.
Le Mans Master
Joined: Feb 2008
Posts: 7,876
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From: Toronto Ontario
Found this discussion very useful since I'm about at the point of ordering a Tremec. Like others here, trying to decide between the 500, 600, and 600RR. I've got a 63 convertible with a 355 hp ZZ4 engine. The 3.36 rear needs to be rebuilt, so I've pretty much got my choice of rear end ratio.
Any thoughts on what rear ends work best for each of the Tremecs? Or, has anybody got a combination they really like? I'm running rpm/speed and shift point calculators but with 3 transmissions and a bunch of rear ends, its a ton of data to try to make sense of.
Any thoughts on what rear ends work best for each of the Tremecs? Or, has anybody got a combination they really like? I'm running rpm/speed and shift point calculators but with 3 transmissions and a bunch of rear ends, its a ton of data to try to make sense of.
Burning Brakes
Joined: Jun 2004
Posts: 1,123
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From: Sandia Park NM
I have been thinking on the same lines. Around here the average speed on the highway/freeways seems to be in the upper 70's. I believe I'm running 3.70s. At those speeds the engine is screaming at 3500rpm plus.
I was thinking if there is enough of us interested in putting together a group buy we should be able to negotiate a discount of at least 20%, otherwise it's not worth it.
Dennis
I was thinking if there is enough of us interested in putting together a group buy we should be able to negotiate a discount of at least 20%, otherwise it's not worth it.
Dennis
Le Mans Master
Joined: Jan 2005
Posts: 8,226
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From: Lake Wylie SC
Found this discussion very useful since I'm about at the point of ordering a Tremec. Like others here, trying to decide between the 500, 600, and 600RR. I've got a 63 convertible with a 355 hp ZZ4 engine. The 3.36 rear needs to be rebuilt, so I've pretty much got my choice of rear end ratio.
Any thoughts on what rear ends work best for each of the Tremecs? Or, has anybody got a combination they really like? I'm running rpm/speed and shift point calculators but with 3 transmissions and a bunch of rear ends, its a ton of data to try to make sense of.
Any thoughts on what rear ends work best for each of the Tremecs? Or, has anybody got a combination they really like? I'm running rpm/speed and shift point calculators but with 3 transmissions and a bunch of rear ends, its a ton of data to try to make sense of.
The standard 600 IMO is only needed when you are running 4:11 or steeper and even more so because the 5th gear in the standard is not the beefiest gear in the world.
Doug
Le Mans Master
Joined: Mar 2005
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From: Rocklin California
How many RPM's you can produce needs to be considered. If you can turn 6500 I would go with a 600RR and a 3.70 gear .......or in your case a 3:55 if you are limited to 6000 or less.
The standard 600 IMO is only needed when you are running 4:11 or steeper and even more so because the 5th gear in the standard is not the beefiest gear in the world.
Doug
The standard 600 IMO is only needed when you are running 4:11 or steeper and even more so because the 5th gear in the standard is not the beefiest gear in the world.
Doug
It really cuts down the noise when cruising at less than 2000 RPM
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From: Clinton Township MI
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67-427ci,
Your visual is, in spades, a convincing argument FOR this trans swap.
Along with considering the rear gears you want to use, I do think the key to what TKO to buy will be HOW you use your car for most of the time you own it.
I've heard (and you folks with this tranny installed will hopefully chime in) that the downside of this swap is the fact that you cannot speed shift or drag race or autocross with this tranny. Also, this is more of a question, is the spread between gears (1st through 4th on a .64 OD) not suited for this type of driving? So, I'm thinking for those who would spend their time doing this, that would be a stopper.
For the rest of us who would do this (drag race/autocross) occasionally, it's got to be an upper to slip that tranny into 5th and enjoy driving at 75 mph with a 3.70:1 posi @ 2,300 r's.
Jim
Your visual is, in spades, a convincing argument FOR this trans swap.
Along with considering the rear gears you want to use, I do think the key to what TKO to buy will be HOW you use your car for most of the time you own it.
I've heard (and you folks with this tranny installed will hopefully chime in) that the downside of this swap is the fact that you cannot speed shift or drag race or autocross with this tranny. Also, this is more of a question, is the spread between gears (1st through 4th on a .64 OD) not suited for this type of driving? So, I'm thinking for those who would spend their time doing this, that would be a stopper.
For the rest of us who would do this (drag race/autocross) occasionally, it's got to be an upper to slip that tranny into 5th and enjoy driving at 75 mph with a 3.70:1 posi @ 2,300 r's.
Jim
Le Mans Master
Joined: Oct 2000
Posts: 8,897
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From: Santa Ana CA
67-427ci,
I've heard (and you folks with this tranny installed will hopefully chime in) that the downside of this swap is the fact that you cannot speed shift or drag race or autocross with this tranny. Also, this is more of a question, is the spread between gears (1st through 4th on a .64 OD) not suited for this type of driving? So, I'm thinking for those who would spend their time doing this, that would be a stopper.
For the rest of us who would do this (drag race/autocross) occasionally, it's got to be an upper to slip that tranny into 5th and enjoy driving at 75 mph with a 3.70:1 posi @ 2,300 r's.
Jim
I've heard (and you folks with this tranny installed will hopefully chime in) that the downside of this swap is the fact that you cannot speed shift or drag race or autocross with this tranny. Also, this is more of a question, is the spread between gears (1st through 4th on a .64 OD) not suited for this type of driving? So, I'm thinking for those who would spend their time doing this, that would be a stopper.
For the rest of us who would do this (drag race/autocross) occasionally, it's got to be an upper to slip that tranny into 5th and enjoy driving at 75 mph with a 3.70:1 posi @ 2,300 r's.
Jim
Only reason I could see for not autocrossing is that it would take you out of stock class (if noticed).
Also, the 1-4 spread is very similar to the M20 with the first 3 gears being only slightly lower (4th is the same 1:1).
When I did the math, the TKO 600 in 1st gear with a 3.70:1 would be about the same as the Muncie M20 with a 3.90:1 gear, which is really about ideal for my driving and wheel combination.
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From: Camp Verde AZ
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How fast is tHe shifting on these? Drag race oriented question. Are they M21 fast, or does it take longer to go from gear to gear?
Thanks,
Doug
Thanks,
Doug