Which Tremec to run?
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Which Tremec to run?
Im looking to convert my 73 with a tremec 5 speed. It has 3.36 gears. Im not happy with the bottom end performance coupled with the th400. ive noticed that they make a couple of different 1st gear ratio's. 3.27 and 2.87. Which one would work better for me? Thanks
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
Since we know nothing about your engine or its cam specs and power band, Im going to give a generic, but likely satisfactory answer.
TKO 600 with .82 o.d
Perhaps the .64 o.d would work, but since we know nothing about the rest of your combo, the .82 would be very safe. Sort of like having a 2.73 rear on the highway. Either model TKO 600 will feel like 3.90's in 1st.
The tko 500 will be almost the equivalent of having 4.56's in 1st
TKO 600 with .82 o.d
Perhaps the .64 o.d would work, but since we know nothing about the rest of your combo, the .82 would be very safe. Sort of like having a 2.73 rear on the highway. Either model TKO 600 will feel like 3.90's in 1st.
The tko 500 will be almost the equivalent of having 4.56's in 1st
Thread Starter
Intermediate
Joined: Jul 2014
Posts: 46
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Since we know nothing about your engine or its cam specs and power band, Im going to give a generic, but likely satisfactory answer.
TKO 600 with .82 o.d
Perhaps the .64 o.d would work, but since we know nothing about the rest of your combo, the .82 would be very safe. Sort of like having a 2.73 rear on the highway. Either model TKO 600 will feel like 3.90's in 1st.
The tko 500 will be almost the equivalent of having 4.56's in 1st
TKO 600 with .82 o.d
Perhaps the .64 o.d would work, but since we know nothing about the rest of your combo, the .82 would be very safe. Sort of like having a 2.73 rear on the highway. Either model TKO 600 will feel like 3.90's in 1st.
The tko 500 will be almost the equivalent of having 4.56's in 1st
Thanks, engine, 383, 2V flat tops, Brodix ik200 heads, crower 00468 cam. 225/232@.050, .535/.550". powerband is supposed to be 2200-5800.
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
Heres how I feel...
The tko 600 with .64, and a hypothetical 27" tall tire and your 3.36 gear (according to hurst driveline calculator):
5th gear
70mph 1871rpm
65mph 1737rpm
60mph 1603rpm
4th gear
70mph 2923rpm
65mph 2714rpm
60mph 2505rpm
There is a good chance your motor starts to feel a little soggy in that 1600 rpm territory, but you've driven the combo already, so maybe you are still making usable torque there.
As you can see, there is a huge gap at 4th and 5th. If you are driving in traffic with some volume, and you slow down to the 60mph or less range, you are going to downshift... rpms will come up by a grand. Maybe you get back up to 70 for a moment, now your at almost 3k... your going to shift.. brings you back down to 1871... and you could keep playing this back and forth game. A .82 OD will not be like this.
70mph 2397rpm
65mph 2226rpm
60mph 2054rpm
These rpms are certainly acceptable for 5th gear cruising. Even 80mph is 2739rpms. Certainly livable at that speed.
Im sure plenty of guys here are going to say get the .64 and I know there are some with less gear and the .64. However... do a search of .82 vs .64 on this site and others, and you will see people saying "I wish I did the ,82 instead of the ,64)
FWIW, I have 3.55 gears and a Richmond with .77 OD. I find the spread from 4th the 5th perfect. I had never driven my motor before, and as it turns out, it probably could have chugged down in the rpm a little lower than I would have thought, but not much. However, Im still glad I chose this set up of gearing.
The tko 600 with .64, and a hypothetical 27" tall tire and your 3.36 gear (according to hurst driveline calculator):
5th gear
70mph 1871rpm
65mph 1737rpm
60mph 1603rpm
4th gear
70mph 2923rpm
65mph 2714rpm
60mph 2505rpm
There is a good chance your motor starts to feel a little soggy in that 1600 rpm territory, but you've driven the combo already, so maybe you are still making usable torque there.
As you can see, there is a huge gap at 4th and 5th. If you are driving in traffic with some volume, and you slow down to the 60mph or less range, you are going to downshift... rpms will come up by a grand. Maybe you get back up to 70 for a moment, now your at almost 3k... your going to shift.. brings you back down to 1871... and you could keep playing this back and forth game. A .82 OD will not be like this.
70mph 2397rpm
65mph 2226rpm
60mph 2054rpm
These rpms are certainly acceptable for 5th gear cruising. Even 80mph is 2739rpms. Certainly livable at that speed.
Im sure plenty of guys here are going to say get the .64 and I know there are some with less gear and the .64. However... do a search of .82 vs .64 on this site and others, and you will see people saying "I wish I did the ,82 instead of the ,64)
FWIW, I have 3.55 gears and a Richmond with .77 OD. I find the spread from 4th the 5th perfect. I had never driven my motor before, and as it turns out, it probably could have chugged down in the rpm a little lower than I would have thought, but not much. However, Im still glad I chose this set up of gearing.
Last edited by Big Block Dave; Sep 21, 2017 at 02:34 PM. Reason: Move numbers for visibility
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Not really true. I have to slip the clutch with 2.87 and the 355 rears and. 64 forces you to drive fast in od
Any first gear drive ratio up around 11 is good
But you have to think about the future and 3.73 and tko 600 is a good combo
Any first gear drive ratio up around 11 is good
But you have to think about the future and 3.73 and tko 600 is a good combo
Melting Slicks
Joined: Jun 2011
Posts: 3,116
Likes: 598
So it depends on how you like to drive.
eg
if you are someone that enjoys off the line acceleration for 2-3 sec
, likes tires spin off the line without much effort . 1/4 mile drag racing , street driving where hitting the gas for 2-3 seconds pushed back in your seat, then you will fit in the category higher ratio 1st gears with higher rear ratios.
Since you stated "bottom end performance"
You don't have enough HP / Torque (Motor) to satisfy you,
You can mask the feeling buy changing gears but I find its better to have a goal of how "fast you want the car to be"
1/4 mile time or 1/4 mile MPH, or if road racing laptimes that gives you the feeling you want.
For street driving you cannot have everything. hard launches + highway driveability without going to a 6 speed. (2 over drive gears)
I would first find a car that has the performance of what you want, then you will get an idea of what it takes to get that feeling.
eg take a C7 (Z51) corvette manual car and see if this gives you the smile you are looking for. Then you know you need 450+ HP 2.97 first gear etc.
Last edited by cagotzmann; Sep 18, 2017 at 11:33 AM.
Thread Starter
Intermediate
Joined: Jul 2014
Posts: 46
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I have a T56 Magnum 6 Speed 2.66 first gear and 3.08 Rear. I find this very drivable for street + for the track I drive at, perfect for track days.
So it depends on how you like to drive.
eg
if you are someone that enjoys off the line acceleration for 2-3 sec
, likes tires spin off the line without much effort . 1/4 mile drag racing , street driving where hitting the gas for 2-3 seconds pushed back in your seat, then you will fit in the category higher ratio 1st gears with higher rear ratios.
Since you stated "bottom end performance"
You don't have enough HP / Torque (Motor) to satisfy you,
You can mask the feeling buy changing gears but I find its better to have a goal of how "fast you want the car to be"
1/4 mile time or 1/4 mile MPH, or if road racing laptimes that gives you the feeling you want.
For street driving you cannot have everything. hard launches + highway driveability without going to a 6 speed. (2 over drive gears)
I would first find a car that has the performance of what you want, then you will get an idea of what it takes to get that feeling.
eg take a C7 (Z51) corvette manual car and see if this gives you the smile you are looking for. Then you know you need 450+ HP 2.97 first gear etc.
So it depends on how you like to drive.
eg
if you are someone that enjoys off the line acceleration for 2-3 sec
, likes tires spin off the line without much effort . 1/4 mile drag racing , street driving where hitting the gas for 2-3 seconds pushed back in your seat, then you will fit in the category higher ratio 1st gears with higher rear ratios.
Since you stated "bottom end performance"
You don't have enough HP / Torque (Motor) to satisfy you,
You can mask the feeling buy changing gears but I find its better to have a goal of how "fast you want the car to be"
1/4 mile time or 1/4 mile MPH, or if road racing laptimes that gives you the feeling you want.
For street driving you cannot have everything. hard launches + highway driveability without going to a 6 speed. (2 over drive gears)
I would first find a car that has the performance of what you want, then you will get an idea of what it takes to get that feeling.
eg take a C7 (Z51) corvette manual car and see if this gives you the smile you are looking for. Then you know you need 450+ HP 2.97 first gear etc.
Thanks, my last 72 also had a 383 with a m21 with the 3.36 gears and i loved the whole combination. not so much with this auto. driving a newer car makes sense to figure out what combo i like. thanks again!
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Thread Starter
Intermediate
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Heres how I feel...
The tko 600 with .64, and a hypothetical 27" tall tire and your 3.36 gear (according to hurst driveline calculator):
5th gear
70mph 1871rpm
65mph 1737rpm
60mph 1603rpm
4th gear
70mph 2923rpm
65mph 2714rpm
60mph 2505rpm
There is a good chance your motor starts to feel a little soggy in that 1600 rpm territory, but you've driven the combo already, so maybe you are still making usable torque there.
As you can see, there is a huge gap at 5th and 6th. If you are driving in traffic with some volume, and you slow down to the 60mph or less range, you are going to downshift... rpms will come up by a grand. Maybe you get back up to 70 for a moment, now your at almost 3k... your going to shift.. brings you back down to 1871... and you could keep playing this back and forth game. A .82 OD will not be like this.
70mph 2397rpm
65mph 2226rpm
60mph 2054rpm
These rpms are certainly acceptable for 5th gear cruising. Even 80mph is 2739rpms. Certainly livable at that speed.
Im sure plenty of guys here are going to say get the .64 and I know there are some with less gear and the .64. However... do a search of .82 vs .64 on this site and others, and you will see people saying "I wish I did the ,82 instead of the ,64)
FWIW, I have 3.55 gears and a Richmond with .77 OD. I find the spread from 4th the 5th perfect. I had never driven my motor before, and as it turns out, it probably could have chugged down in the rpm a little lower than I would have thought, but not much. However, Im still glad I chose this set up of gearing.
The tko 600 with .64, and a hypothetical 27" tall tire and your 3.36 gear (according to hurst driveline calculator):
5th gear
70mph 1871rpm
65mph 1737rpm
60mph 1603rpm
4th gear
70mph 2923rpm
65mph 2714rpm
60mph 2505rpm
There is a good chance your motor starts to feel a little soggy in that 1600 rpm territory, but you've driven the combo already, so maybe you are still making usable torque there.
As you can see, there is a huge gap at 5th and 6th. If you are driving in traffic with some volume, and you slow down to the 60mph or less range, you are going to downshift... rpms will come up by a grand. Maybe you get back up to 70 for a moment, now your at almost 3k... your going to shift.. brings you back down to 1871... and you could keep playing this back and forth game. A .82 OD will not be like this.
70mph 2397rpm
65mph 2226rpm
60mph 2054rpm
These rpms are certainly acceptable for 5th gear cruising. Even 80mph is 2739rpms. Certainly livable at that speed.
Im sure plenty of guys here are going to say get the .64 and I know there are some with less gear and the .64. However... do a search of .82 vs .64 on this site and others, and you will see people saying "I wish I did the ,82 instead of the ,64)
FWIW, I have 3.55 gears and a Richmond with .77 OD. I find the spread from 4th the 5th perfect. I had never driven my motor before, and as it turns out, it probably could have chugged down in the rpm a little lower than I would have thought, but not much. However, Im still glad I chose this set up of gearing.
i always thought the 3.55 was a great all around gear. what is the ratio in your first gear?
Thread Starter
Intermediate
Joined: Jul 2014
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------------------------
i agree, im sure ill be getting slammed for this, but i recently sold my 2012 mustang gt with a 6sp with 3.73's and loved the power delivery in all the gears. i was just hoping i could get the right tranny with the lower gears to go with my 3.36's. OD is not a big deal if i can keep my current gears.
Race Director
Joined: Mar 2016
Posts: 14,402
Likes: 8,209
From: Napa Valley California
With the .64 you will be shifting a lot on the open highway. Going up a slight incline you might feel the engine bog to the point that you will shift because you are trying to keep the rpm's a little higher. When you do shift into fourth you will cringe at the steep increase in rpm's.
The .82 won't decrease the rpm's as low as you might want however as stated above they are acceptable for highway driving.
The six speed option gives you the in between gearing but check the 6th gear ratio as on some transmissions the 6th gear is so high that those using them say 6th gear is a waste because they never get to 6th gear.
My 73 has the 454, TH400 and 3.36 gears.
I'm also looking at what option will work best.
I'm considering the TKO 600 .82 option or a built 2004R O.D. auto
The .82 won't decrease the rpm's as low as you might want however as stated above they are acceptable for highway driving.
The six speed option gives you the in between gearing but check the 6th gear ratio as on some transmissions the 6th gear is so high that those using them say 6th gear is a waste because they never get to 6th gear.
My 73 has the 454, TH400 and 3.36 gears.
I'm also looking at what option will work best.
I'm considering the TKO 600 .82 option or a built 2004R O.D. auto
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
Thread Starter
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Joined: Jul 2014
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Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
7020526B 5 speed overdrive 2.89 1st.
I will say this much, it fits really with just a modification to the crossmember mount BUT, and this is a big BUT....
While I like this transmission, after 150 miles it had to come out. I thought it was just a loose shifter issue causing problems with 2nd gear. Fortunately I had access to one of the best men in the business and he went through the box and corrected several issues that it left the factory with.
This is hearsay, but I met another gentleman whom described a scenario involving a friend that sent theirs back to the manufacturer multiple times under warranty.
Thread Starter
Intermediate
Joined: Jul 2014
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7020526B 5 speed overdrive 2.89 1st.
I will say this much, it fits really with just a modification to the crossmember mount BUT, and this is a big BUT....
While I like this transmission, after 150 miles it had to come out. I thought it was just a loose shifter issue causing problems with 2nd gear. Fortunately I had access to one of the best men in the business and he went through the box and corrected several issues that it left the factory with.
This is hearsay, but I met another gentleman whom described a scenario involving a friend that sent theirs back to the manufacturer multiple times under warranty.
I will say this much, it fits really with just a modification to the crossmember mount BUT, and this is a big BUT....
While I like this transmission, after 150 miles it had to come out. I thought it was just a loose shifter issue causing problems with 2nd gear. Fortunately I had access to one of the best men in the business and he went through the box and corrected several issues that it left the factory with.
This is hearsay, but I met another gentleman whom described a scenario involving a friend that sent theirs back to the manufacturer multiple times under warranty.
==
Youd think that when you buy a $3k plus transmission, you wouldnt have any problems. Now somthing else to consider while debating. Thanks for the info. much appreciated. what is your rear axle ratio?
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
I have a 3.55 rear. The.82 Tremec would be very similar to the ratios in my transmission. Before I went with the Richmond that was the unit I had my eye on.
Even with the .23 reduction of gearing that I get (you will have .18.. quite negligible difference), I find the overdrive really changed the car. There have been times where I thought another gear to shift to would be novel, but as a general package, its lightyears ahead of having a 4 speed.
Melting Slicks
Joined: Mar 2006
Posts: 3,456
Likes: 102
From: Piedmont Va
St. Jude Donor '11-'12-'13,'19-'20
I have almost the same setup but my diff is 3.73. I went TKO600 (2.87 1st) and the .64 5th. Its really great but I there is a big drop 4-5. think I would do the .82 5th if I could go back. So for your application I would go with TKO600/.82. When I did mine three summers ago I would have gone with Richmond but there were none to be had at the time and back orders were 6 months. But I'm more than happy with the tremec. 
Thread Starter
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I have almost the same setup but my diff is 3.73. I went TKO600 (2.87 1st) and the .64 5th. Its really great but I there is a big drop 4-5. think I would do the .82 5th if I could go back. So for your application I would go with TKO600/.82. When I did mine three summers ago I would have gone with Richmond but there were none to be had at the time and back orders were 6 months. But I'm more than happy with the tremec.
$2450 for tranny
$500 for hyd clutch set up
$1200 for install kit.
im not balking at the tranny or clutch set up, but $1200 for a install kit kinda throws me back a bit. but the richmond is about $3600 and hope i get a good one. is there a more economical route other than the install kit?
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
What you are seeing cost wise is exactly what drove me into the arms of the Richmond. The tremec costs just the same in the end.
I had also read many reviews about tricky 2-3 shifts on the tremec This also pushed me toward the Richmond.
The Richmond takes up same space as muncie, re-uses your original driveshaft, speedometer cable, and comes with a reverse light adapter. It comes with a shifter, that required slight enlarging of shifter hole in floor. Crossmember would need to be removable, and crossmember mount shortened and lowered, and use short gm energy suspension mount.
On paper it's a home run, but like I said, mine was a problem child.
I had also read many reviews about tricky 2-3 shifts on the tremec This also pushed me toward the Richmond.
The Richmond takes up same space as muncie, re-uses your original driveshaft, speedometer cable, and comes with a reverse light adapter. It comes with a shifter, that required slight enlarging of shifter hole in floor. Crossmember would need to be removable, and crossmember mount shortened and lowered, and use short gm energy suspension mount.
On paper it's a home run, but like I said, mine was a problem child.
Last edited by Big Block Dave; Sep 21, 2017 at 02:30 PM. Reason: Spelling
Burning Brakes
Joined: Jun 2010
Posts: 1,165
Likes: 93
From: Bellmore NY
In addition to the above, I do genuinely like the Richmond, but there was obvious aggravation. I had the opportunity to have magic performed on it before I put it in my car. I felt that since it was new it should have been satisfactory. In hindsight I should have done that...
Anyway, I have often said, if i could go back in time, I would have put in 3.08s instead of swapping in 3.55s, and put in an old 4+1 richmond/Nash.
At this point im satisfied with my choice, but again the initial experience was disappointing.
Anyway, I have often said, if i could go back in time, I would have put in 3.08s instead of swapping in 3.55s, and put in an old 4+1 richmond/Nash.
At this point im satisfied with my choice, but again the initial experience was disappointing.