TKO-600 From WHO?
Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
Couple of random thoughts.
Forget the 621 bell housing. With that much power, get an SFI approved bell housing. Much safer.
Also, start looking for better clutch options. You should also plan a rear end rebuild. It will be a question of when, not if.
As for the 434 small block, go single plane. You will still have more than enough torque to get off the line. The single plane will actually help since too much torque will just smoke the tires off the line. Most dual planes cannot feed that big a motor.
Lastly, look into the T-56 Magnum. That way, you get a useable 5th gear and and still have a really tall OD 6th for highway cruising. Live mine.
Forget the 621 bell housing. With that much power, get an SFI approved bell housing. Much safer.
Also, start looking for better clutch options. You should also plan a rear end rebuild. It will be a question of when, not if.
As for the 434 small block, go single plane. You will still have more than enough torque to get off the line. The single plane will actually help since too much torque will just smoke the tires off the line. Most dual planes cannot feed that big a motor.
Lastly, look into the T-56 Magnum. That way, you get a useable 5th gear and and still have a really tall OD 6th for highway cruising. Live mine.
Thread Starter
Racer
Joined: Nov 2015
Posts: 250
Likes: 34
From: Jackson SC
Couple of random thoughts.
Forget the 621 bell housing. With that much power, get an SFI approved bell housing. Much safer.
Also, start looking for better clutch options. You should also plan a rear end rebuild. It will be a question of when, not if.
As for the 434 small block, go single plane. You will still have more than enough torque to get off the line. The single plane will actually help since too much torque will just smoke the tires off the line. Most dual planes cannot feed that big a motor.
Lastly, look into the T-56 Magnum. That way, you get a useable 5th gear and and still have a really tall OD 6th for highway cruising. Live mine.
Forget the 621 bell housing. With that much power, get an SFI approved bell housing. Much safer.
Also, start looking for better clutch options. You should also plan a rear end rebuild. It will be a question of when, not if.
As for the 434 small block, go single plane. You will still have more than enough torque to get off the line. The single plane will actually help since too much torque will just smoke the tires off the line. Most dual planes cannot feed that big a motor.
Lastly, look into the T-56 Magnum. That way, you get a useable 5th gear and and still have a really tall OD 6th for highway cruising. Live mine.
Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
Thanks for your input/thoughts. I'm going to use a Centerforce Dual Friction Series Clutch, its holding capacity is in the 550 - 600 ft lb range. It's new, hopefully, it will fit the need for now. Using your advice I will likely look into the tougher bellhousing - Thanks. As far as the rear of the car is concerned, everything is new and was purchased and installed for a big block application. The six-speed (T-56) is a terrible temptation for me - but I will still have the same problem - For the amount of hp I want to target, the cruise speed for the cam is going to land me in the 22 - 2,600 rpm range (for cruse - not optimal power). A taller overdrive that dips the motor below these levels would likely demand a down-shift to even pass slower traffic on the interstate. I'm not sure that is what I want to do....hmmmmmmm says a thinking man hmmmmmm. Trust me - I want the .63 for the economy (laughably) but I also want to use the gear for more than just interstate driving. I'm still wading through the options.... Thank you for your advice.
Tremec now offers a Magnum with the 2.97 first/.63 6th. Just $$$. Maybe I can find some interested in a lightly used close ration T-56 Magnum.
Just remember, stock big blocks were only 400-500 hp. Not as strong as most people think. That is why I had Gary Ramadie build me a 12 bolt rear good for 700 rear wheel hp. Overkill.
The DF is a good clutch but on the ragged edge of what you are planning. I would look into the McLeod RST/RXT series. I have an RST with mechanical linkage and it is lighter than my old DF clutch.
Out of curiosity, have you driven a 600+ hp car on the street? My big block dynoed at 413 rwhp and it is plenty. My tuner says I could get 50+ more if I replaced the sidepipes with a better exhaust, but the wife says I have enough power and she likes the pipes.
Last edited by SteveG75; Jul 22, 2020 at 09:58 AM.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,095
Likes: 4,449
From: Marlton NJ
Here is a slightly updated version of the gear spreadsheet. I corrected a formula or two and added a couple of gearboxes.
I agree with you, with a cam like that a 2200 rpm or so cruise is a great target, not much lower, it probably won't like it.
With that in mind, a TKO 600 with 2.87/.64 gearing and a 3.73 rear would work terrific. 10.7 first gear and 2100 rpm cruise.
For a T-56 combo, the .TUET11009LS with it's 2.66 first and .63 OD would work best with 4.11 gears. First gear would be 10.9 and 70 mph cruise would be 2300 rpm.
Shifting rpm drops are around 1100 for the 5spd trans and 900 for the 6 spd. Overall gear ratio spread is 4.5 for the 5spd and 4.2 for the 6spd.
This is the CR 6 spd. The W.R 6spd version has such a wide gear spread (5.9) I would not recommend it unless you had a milder cammed engine and EFI. The OD is just way too deep. Not too many 6500rpm engines are going to like a 13-1500rpm cruise.
I agree with you, with a cam like that a 2200 rpm or so cruise is a great target, not much lower, it probably won't like it.
With that in mind, a TKO 600 with 2.87/.64 gearing and a 3.73 rear would work terrific. 10.7 first gear and 2100 rpm cruise.
For a T-56 combo, the .TUET11009LS with it's 2.66 first and .63 OD would work best with 4.11 gears. First gear would be 10.9 and 70 mph cruise would be 2300 rpm.
Shifting rpm drops are around 1100 for the 5spd trans and 900 for the 6 spd. Overall gear ratio spread is 4.5 for the 5spd and 4.2 for the 6spd.
This is the CR 6 spd. The W.R 6spd version has such a wide gear spread (5.9) I would not recommend it unless you had a milder cammed engine and EFI. The OD is just way too deep. Not too many 6500rpm engines are going to like a 13-1500rpm cruise.
Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
Here is a slightly updated version of the gear spreadsheet. I corrected a formula or two and added a couple of gearboxes.
I agree with you, with a cam like that a 2200 rpm or so cruise is a great target, not much lower, it probably won't like it.
With that in mind, a TKO 600 with 2.87/.64 gearing and a 3.73 rear would work terrific. 10.7 first gear and 2100 rpm cruise.
For a T-56 combo, the .TUET11009LS with it's 2.66 first and .63 OD would work best with 4.11 gears. First gear would be 10.9 and 70 mph cruise would be 2300 rpm.
Shifting rpm drops are around 1100 for the 5spd trans and 900 for the 6 spd. Overall gear ratio spread is 4.5 for the 5spd and 4.2 for the 6spd.
This is the CR 6 spd. The W.R 6spd version has such a wide gear spread (5.9) I would not recommend it unless you had a milder cammed engine and EFI. The OD is just way too deep. Not too many 6500rpm engines are going to like a 13-1500rpm cruise.
I agree with you, with a cam like that a 2200 rpm or so cruise is a great target, not much lower, it probably won't like it.
With that in mind, a TKO 600 with 2.87/.64 gearing and a 3.73 rear would work terrific. 10.7 first gear and 2100 rpm cruise.
For a T-56 combo, the .TUET11009LS with it's 2.66 first and .63 OD would work best with 4.11 gears. First gear would be 10.9 and 70 mph cruise would be 2300 rpm.
Shifting rpm drops are around 1100 for the 5spd trans and 900 for the 6 spd. Overall gear ratio spread is 4.5 for the 5spd and 4.2 for the 6spd.
This is the CR 6 spd. The W.R 6spd version has such a wide gear spread (5.9) I would not recommend it unless you had a milder cammed engine and EFI. The OD is just way too deep. Not too many 6500rpm engines are going to like a 13-1500rpm cruise.
Close ratio: https://www.summitracing.com/parts/awr-tuet11009
First Gear Ratio:2.66:1
Second Gear Ratio:1.78:1
Third Gear Ratio:1.30:1
Fourth Gear Ratio:1.00:1
Fifth Gear Ratio:0.80:1
Sixth Gear Ratio:0.63:1
NEW wide ratio T-56: https://www.summitracing.com/parts/awr-tuet16885
First Gear Ratio:2.97:1
Second Gear Ratio:2.10:1
Third Gear Ratio:1.46:1
Fourth Gear Ratio:1.00:1
Fifth Gear Ratio:0.80:1
Sixth Gear Ratio:0.63:1
OLD wide ratio: https://www.summitracing.com/parts/awr-tuet11012
First Gear Ratio:2.97:1
Second Gear Ratio:2.10:1
Third Gear Ratio:1.46:1
Fourth Gear Ratio:1.00:1
Fifth Gear Ratio:0.74:1
Sixth Gear Ratio:0.50:1
I would love to swap my CR for one to get the deeper first (right now I am 9.9 multiplication ratio in first) but the cost is prohibitive unless I can get a couple of grand for the current tranny. I think the new WR with a 3.73 rear would be perfect.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,095
Likes: 4,449
From: Marlton NJ
I agree that would be a much better CR gear set. I still do not see that on the Tremec site tho.
It would work real well with 3.73s, give a 11.1 first gear and cruise at 2100 at 70. The cruise would be about 200 lower than the WR/4.11 setup.
However the OP may need the extra cruise rpm. He has a strongly cammed 383.
For your FI 454 BB, the CR/3.73 combo may well work better as you suggested.
It would work real well with 3.73s, give a 11.1 first gear and cruise at 2100 at 70. The cruise would be about 200 lower than the WR/4.11 setup.
However the OP may need the extra cruise rpm. He has a strongly cammed 383.
For your FI 454 BB, the CR/3.73 combo may well work better as you suggested.
Last edited by leigh1322; Jul 22, 2020 at 02:39 PM.
Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
I agree that would be a much better CR gear set. I still do not see that on the Tremec site tho.
It would work real well with 3.73s, give a 11.1 first gear and cruise at 2100 at 70. The cruise would be about 200 lower than the WR/4.11 setup.
However the OP may need the extra cruise rpm. He has a strongly cammed 383.
For your FI 454 BB, the CR/3.73 combo may well work better as you suggested.
It would work real well with 3.73s, give a 11.1 first gear and cruise at 2100 at 70. The cruise would be about 200 lower than the WR/4.11 setup.
However the OP may need the extra cruise rpm. He has a strongly cammed 383.
For your FI 454 BB, the CR/3.73 combo may well work better as you suggested.
Current config 2.66 x 3.73 = 9.92
Original T-10 2.64 x 3.36 = 8.87
M22 combos 2.20 x 4.10 = 9.02
I was just spoiled when I had the Tremec 3550 behind my small block. 3.27 first; 3.27 x 3.36 = 10.99. But first gear was very short with a 6k redline.
Thread Starter
Racer
Joined: Nov 2015
Posts: 250
Likes: 34
From: Jackson SC
You may need a stronger rear and then you can make the gears match the transmission instead of the other way round. Mine is a 12 bolt with 3.73 gears. Almost perfect with a 2.66 first and .63 6th. Sometimes, I wish for a 4.11 rear for the first gear ratio though. Right now, 2200 rpm gets me 75 mph in 6th. Perfect OD.
Tremec now offers a Magnum with the 2.97 first/.63 6th. Just $$$. Maybe I can find some interested in a lightly used close ration T-56 Magnum.
Just remember, stock big blocks were only 400-500 hp. Not as strong as most people think. That is why I had Gary Ramadie build me a 12 bolt rear good for 700 rear wheel hp. Overkill.
The DF is a good clutch but on the ragged edge of what you are planning. I would look into the McLeod RST/RXT series. I have an RST with mechanical linkage and it is lighter than my old DF clutch.
Out of curiosity, have you driven a 600+ hp car on the street? My big block dynoed at 413 rwhp and it is plenty. My tuner says I could get 50+ more if I replaced the sidepipes with a better exhaust, but the wife says I have enough power and she likes the pipes.
Tremec now offers a Magnum with the 2.97 first/.63 6th. Just $$$. Maybe I can find some interested in a lightly used close ration T-56 Magnum.
Just remember, stock big blocks were only 400-500 hp. Not as strong as most people think. That is why I had Gary Ramadie build me a 12 bolt rear good for 700 rear wheel hp. Overkill.
The DF is a good clutch but on the ragged edge of what you are planning. I would look into the McLeod RST/RXT series. I have an RST with mechanical linkage and it is lighter than my old DF clutch.
Out of curiosity, have you driven a 600+ hp car on the street? My big block dynoed at 413 rwhp and it is plenty. My tuner says I could get 50+ more if I replaced the sidepipes with a better exhaust, but the wife says I have enough power and she likes the pipes.
My current motor (383) is producing 500 hp and 550 ft. lbs and is relatively tame with a real nice chop. The 600 hp 434 is being put together now. I have a hp target but want to build as much torque as I can. I'm not a true grit drag racer and my car will likely see the track a few times out of curiosity but simply for time slips - not true competition. I do, however, want to surprise the C6, 7, and 8 folks with some 1972 tail lights....
I'm going to check the posts for the better tire options for traction - not taring everything out the backend - but not sliding sideways in 4th gear either. This little 383 will slip out from under you in a heartbeat on BF Goodrich tires - I have to do something better for traction... I couldn't find much info on the McLeod RS/RXT for the TKO-600. I may not be looking in the right place or I may be asking the wrong questions. The Tremec isn't usually coupled with a SB 72 Vette so I probably need to revise my query. The problem is - I'm not sure how to direct my question in order to get the information I need. Any suggestions?
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Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
What is the tallest gear that will fit our carrier? 355 or 373? Would a new carrier be needed for the 4 series?
My current motor (383) is producing 500 hp and 550 ft. lbs and is relatively tame with a real nice chop. The 600 hp 434 is being put together now. I have a hp target but want to build as much torque as I can. I'm not a true grit drag racer and my car will likely see the track a few times out of curiosity but simply for time slips - not true competition. I do, however, want to surprise the C6, 7, and 8 folks with some 1972 tail lights.... I'm going to check the posts for the better tire options for traction - not taring everything out the backend - but not sliding sideways in 4th gear either. This little 383 will slip out from under you in a heartbeat on BF Goodrich tires - I have to do something better for traction...
I couldn't find much info on the McLeod RS/RXT for the TKO-600. I may not be looking in the right place or I may be asking the wrong questions. The Tremec isn't usually coupled with a SB 72 Vette so I probably need to revise my query. The problem is - I'm not sure how to direct my question in order to get the information I need. Any suggestions?
My current motor (383) is producing 500 hp and 550 ft. lbs and is relatively tame with a real nice chop. The 600 hp 434 is being put together now. I have a hp target but want to build as much torque as I can. I'm not a true grit drag racer and my car will likely see the track a few times out of curiosity but simply for time slips - not true competition. I do, however, want to surprise the C6, 7, and 8 folks with some 1972 tail lights....
I'm going to check the posts for the better tire options for traction - not taring everything out the backend - but not sliding sideways in 4th gear either. This little 383 will slip out from under you in a heartbeat on BF Goodrich tires - I have to do something better for traction...I couldn't find much info on the McLeod RS/RXT for the TKO-600. I may not be looking in the right place or I may be asking the wrong questions. The Tremec isn't usually coupled with a SB 72 Vette so I probably need to revise my query. The problem is - I'm not sure how to direct my question in order to get the information I need. Any suggestions?
As for the rear, get in touch with Gary Ramadie (GTR1999). He is a straight shooter and will be able to give you an honest assessment on what you need.
Last edited by SteveG75; Jul 23, 2020 at 08:27 AM.
Thread Starter
Racer
Joined: Nov 2015
Posts: 250
Likes: 34
From: Jackson SC
You can run any clutch that fits. The danger with tires that hook is that you are putting additional stress on the half shafts and U-joints. I have Mickey Thompson ST tires. No traction in 1st at all, better in higher gears (I use VBP Smart Struts so get almost no rear camber change on squat).
As for the rear, get in touch with Gary Ramadie (GTR1999). He is a straight shooter and will be able to give you an honest assessment on what you need.
As for the rear, get in touch with Gary Ramadie (GTR1999). He is a straight shooter and will be able to give you an honest assessment on what you need.