Log in

View Full Version : Best T56 Magnum/ rear gear combo


workng247
02-18-2015, 06:36 AM
Looking to get some input on what you guys would consider the best trans/ rear gear combo for my upcoming 69 Camaro LS swap. I'll be using the LS3 480hp crate engine and a T56 magnum. Looking for best all around street performance. I have original 12 bolt with 3.42 and Truetrac now. Will change gear if necessary. So, which version of the T56 would you recommend and why?

Thanks

Sieg
02-18-2015, 08:22 AM
Is your T56 wide or close ratio?

I had 3:31's and went to 3:73 with a 26.6" tire with a close ratio T56 Mag and it's just about right for my needs.

This will help you figure it out: http://www.tremec.com/calculadora.php

workng247
02-18-2015, 08:32 AM
Is your T56 wide or close ratio?

Thats what I am trying to figure out, at this point I can go either way.

I've done the RPM calculators but its hard to get any "feel" from the numbers.

Schwartz Perf
02-18-2015, 04:51 PM
With your combo i'd definitely do the close-ratio. If you had a taller gear like 4.10 then the wide would be a little better.

If you don't have a source yet for the T56 or other parts, feel free to PM me for a quote on that stuff!

-Dale

Sieg
02-18-2015, 10:10 PM
I had a '94 1LE Camaro with a wide ratio T56 for a couple years as a daily driver, for my personal tastes the close ratio gearing is light years better. I don't like a low first gear and a lazy 6th. The close ratio is seamless through the gears no short-shifting to second and over revving 5th to make 6th. I'm running a carb'd Gen 1 SBC with cam that idles at 1K and is rated to make power between 2500-6500....first gear in the close ratio is great.

Without a doubt the T56 is the best mod done on my car over the 25 years I've had it. After three plus years with the trans I still love it everytime I drive it.....it makes me want to just go out and drive.

FWIW - I waited 2 years before changing rear end ratios and spent a lot of time analyzing my typical driving conditions and rpm's, factoring ideals and compromises before I went with 3:73, no regrets.

Vince@Meanstreets
02-18-2015, 11:14 PM
I had a '94 1LE Camaro keyword is "had" and my key phrase was " why don't you still ?"

FWIW - I waited 2 years before changing rear end ratios and spent a lot of time analyzing my typical driving conditions and rpm's, factoring ideals and compromises before I went with 3:73, no regrets.

Truth

Sieg
02-18-2015, 11:44 PM
I should add that I went with an old school mechanic that specializes in differentials and used a Motive gear set. They are silent.....which was something I was worried about as I'd heard many a story of gear whine associated with the 3:73 ratio.

workng247
02-27-2015, 08:36 AM
I had a '94 1LE Camaro with a wide ratio T56 for a couple years as a daily driver, for my personal tastes the close ratio gearing is light years better. I don't like a low first gear and a lazy 6th. The close ratio is seamless through the gears no short-shifting to second and over revving 5th to make 6th. I'm running a carb'd Gen 1 SBC with cam that idles at 1K and is rated to make power between 2500-6500....first gear in the close ratio is great.

Without a doubt the T56 is the best mod done on my car over the 25 years I've had it. After three plus years with the trans I still love it everytime I drive it.....it makes me want to just go out and drive.

FWIW - I waited 2 years before changing rear end ratios and spent a lot of time analyzing my typical driving conditions and rpm's, factoring ideals and compromises before I went with 3:73, no regrets.

OK, thats some good input and confirms what I was thinking.

Now, what about using the factory center console? I was looking at your build and the problems you had with the offset shifter leaking. What did you finally end up with and what would you recommend? Keep it? Move it? Lose it? I'd like to keep it but it seems like the shifter location with it is not ideal. Thoughts? Thanks

workng247
03-03-2015, 08:08 AM
Bump:D

Blake Foster
03-03-2015, 09:30 AM
I should add that I went with an old school mechanic that specializes in differentials and used a Motive gear set. They are silent.....which was something I was worried about as I'd heard many a story of gear whine associated with the 3:73 ratio.

Yes.................. Sometimes, we have switched to US Gear because of the inconsistency of the motive 3.73 sets.
we NORMALLY recommend 3.73 (seems to work for everything ) but I really liked my 3.89 gears

Sieg
03-03-2015, 10:15 AM
Yes.................. Sometimes, we have switched to US Gear because of the inconsistency of the motive 3.73 sets.
we NORMALLY recommend 3.73 (seems to work for everything ) but I really liked my 3.89 gears

Interesting, the old-timer I use does nothing but ring and pinion work. Could be he just sets them up right. :headscratch:

Regarding the ratio it really depends on where and how you drive your car......and the other elements of the equation, power, power curves, trans ratios, and tire height.

IMO - It's really a personal preference that one needs to analyze and factor for themselves.

RdHuggr68
03-03-2015, 07:58 PM
OK, thats some good input and confirms what I was thinking.

Now, what about using the factory center console? I was looking at your build and the problems you had with the offset shifter leaking. What did you finally end up with and what would you recommend? Keep it? Move it? Lose it? I'd like to keep it but it seems like the shifter location with it is not ideal. Thoughts? Thanks

I would be interested Siegs response also. I don't want to get rid of my console!!
Kevin

Sieg
03-03-2015, 09:18 PM
I dumped the OEM panel that encloses the shifter, made my own shift boot and a new panel from 16 gauge sheet metal. The shifter is in located in the forward position on the case, with the OEM panel it works in the rear position. The forward position positions the shifter closer to the steering wheel and forward of the internal gear that slings lubricant directly up onto the shift linkage and seal.

This picture is taken before paint while I was mocking up the gauge pod for the AEM air fuel gauge.

http://photos.smugmug.com/photos/i-NWdn8VR/1/XL/i-NWdn8VR-XL.jpg

RdHuggr68
03-04-2015, 05:28 PM
I dumped the OEM panel that encloses the shifter, made my own shift boot and a new panel from 16 gauge sheet metal. The shifter is in located in the forward position on the case, with the OEM panel it works in the rear position. The forward position positions the shifter closer to the steering wheel and forward of the internal gear that slings lubricant directly up onto the shift linkage and seal.

This picture is taken before paint while I was mocking up the gauge pod for the AEM air fuel gauge.

http://photos.smugmug.com/photos/i-NWdn8VR/1/XL/i-NWdn8VR-XL.jpg

Looks great Sieg, thanks for the info!!:thumbsup:

Nativefx
03-13-2015, 10:15 AM
Is your T56 wide or close ratio?

I had 3:31's and went to 3:73 with a 26.6" tire with a close ratio T56 Mag and it's just about right for my needs.

This will help you figure it out: http://www.tremec.com/calculadora.php

Hi Sieg, my combination will be pretty close to the same once I get finished so i'm interested in your thoughts about the 3:73 gearing in the rear? Do you still find your able to actually use 6th gear? Here in OR the speed limit on the highway is still 55:( but for my purposes I'm going to consider 60-65 mph as that's normally the speed people drive on the highways.

I'm building my car to drive, so even with a 480-500hp LS3 motor, close ratio T56 Mag and 9" rear end, I'd still like it to be fun around town but also useful on the highway for longer trips over 5 hrs. I had considered 3:42 but I don't think that would be very useful for 6th gear very often. I think I should be considering 3:73 or 3:89 to give me the best overall?

Obviously I'm worried about gear whine, so I've been trying to research the best options for either of these as well. I'm seeing mixed reviews of the Motive gear sets, but also understand most consider the ones made in Italy to be better? Until Blakes earlier comment I hadn't heard anyone mention US Gear, so I'll have to do some research on them as well.

Appreciate all the input available through the forum!:thankyou:

Sieg
03-13-2015, 01:42 PM
Hi Sieg, my combination will be pretty close to the same once I get finished so i'm interested in your thoughts about the 3:73 gearing in the rear? Do you still find your able to actually use 6th gear? Here in OR the speed limit on the highway is still 55:( but for my purposes I'm going to consider 60-65 mph as that's normally the speed people drive on the highways.

I'm building my car to drive, so even with a 480-500hp LS3 motor, close ratio T56 Mag and 9" rear end, I'd still like it to be fun around town but also useful on the highway for longer trips over 5 hrs. I had considered 3:42 but I don't think that would be very useful for 6th gear very often. I think I should be considering 3:73 or 3:89 to give me the best overall?

Obviously I'm worried about gear whine, so I've been trying to research the best options for either of these as well. I'm seeing mixed reviews of the Motive gear sets, but also understand most consider the ones made in Italy to be better? Until Blakes earlier comment I hadn't heard anyone mention US Gear, so I'll have to do some research on them as well.

Appreciate all the input available through the forum!:thankyou:
I was cruising a little yesterday 70-80 at 2000-2200 in 6th with a 26.5" rear tire and it's perfect, even with my horribly inferior Holley Ultra XP carb and Gen1 SBC. Around town 35 mph in 3rd gear is 2400ish rpm.

Road speeds at typically 55-65 and 65-75 around here so 5th and 6th are

Tire diameter is a critical factor!

My Motive's are silent, but as mentioned that could have a lot to do with who set them up. Blake has a lot more rear end experience than I. :unibrow:

Nativefx
03-13-2015, 06:36 PM
I was cruising a little yesterday 70-80 at 2000-2200 in 6th with a 26.5" rear tire and it's perfect, even with my horribly inferior Holley Ultra XP carb and Gen1 SBC. Around town 35 mph in 3rd gear is 2400ish rpm.

Road speeds at typically 55-65 and 65-75 around here so 5th and 6th are

Tire diameter is a critical factor!

My Motive's are silent, but as mentioned that could have a lot to do with who set them up. Blake has a lot more rear end experience than I. :unibrow:

Yeah i'm running 325/30/19 tires in the rear which are 26.677 if I recall correctly.

Sieg
03-13-2015, 09:54 PM
3.89 may also work for you, really depends on how you like/want to drive it.

71RS/SS396
03-14-2015, 04:25 AM
If you want quiet gears.... buy Ford gears. I have one disclaimer though... they're more expensive than aftermarket ones. You can buy REM finished Ford gears from C&R Racing.

Nativefx
03-14-2015, 01:40 PM
If you want quiet gears.... buy Ford gears. I have one disclaimer though... they're more expensive than aftermarket ones. You can buy REM finished Ford gears from C&R Racing.

Thanks for the advise. I'll definitely have to look into that as I'm worried about any whine coming from the rear.