Thinking about picking up a T56

[Taz]

I've been thinking about switching over to a T56 when I put the car in the air for a bunch of other upgrades - hopefully in the near future.

If I switch to a T56, I'm leaning toward the 00R-spec tranny, because I just don't think the 2.66 first gear in the Viper-spec unit is enough for a 3.73 rear end - at least, not if I want to do my part to keep my favorite tire companies in business, LOL. Also, I prefer the 00R-spec .80 and .62 overdrive gears to the .74 and .50 ratios. Any opinions on this?
:shrug:

Also, who's my best bet as a vendor for one of these transmissions? I'm leaning toward D&D, but am open to suggestions.

Thanks,

T-

 

[quick01snake]

the guy that bought my car put a 00R spec in it from D&D...careful, it took him almost 2 months to get it, since it was on back order from Tremec....but i definitely would go with that one w/ the shorter first gear and overdrives...if anything you'll get slightly better fuel economy w/ the shorter o/d's than w/ the .50, these engines like to cruise close to 3K rpms...

 

[99SVTAddict]

D&D.

Your right about the 2.66 (Viper 1st gear) and 3.73 gears...it would be a dog. I have 4.30's and almost 600RHP, so for me it seems to be the perfect combo.

The R tranny was my second choice when I was looking at getting my T56.

Oh, the .5 6th gear ratio is nice....but anything under 75-80mph is useless for accelerating to get around traffic if you are in 6th gear.

 

[99COBRA2881]

I went with D&D... great customer service. I ordered my trans then about a week or two later I see they've put the T56 trans and install kit on sale. I call them up and ask about just buying mine recently, they said they'll have to run it past the owner and see if its ok to get me a refund. I get a phone call back same day from the owner (cant remember his name) and he says I'll have a refund check for $150 sent to me. I was very happy the refund covered the cost of shipping. I've got nothing but great things to say about D&D, they answered all my questions as I was deciding on whether to just install a rebuilt T45 or go all out and order a T56.

I like the '00 R spec trans. Viper spec was more $$$ and I really couldnt see the need for anything that it offered. The 26 spline input would be nice insurance but I have just a few mods and am going to keep the car N/A. It all depends on what you want to spend.

 

[Taz]

Thanks, guys. It sounds like I'm leaning the right way on this thing.

Just one more question. Here's the deal ... Part of my resistance to migrating to a 6-speed earlier was my reluctance to toss out my PST CF driveshaft. But a buddy of mine, who has already put a T56 into his '99 Cobra, and who'll be helping me with this installation (if he ever quits blowing up his KB'd Lightning and having to rebuild it! LOL) says that all I have to do is shorten the yoke tube by about an inch, and I'll be able to reuse my same DS.
:dw:

Stay with me, here ... We all know the T56 is longer and so requires a shorter DS, but as Jim explained it to me, the shaft itself will fit between the tranny and the rear end, and those of us who are still running the IRS out back can get away with just slicing a bit off the slip tube to adjust the overall length to accommodate a T56 in place of a T45 or TR3650.

The IRS offers this option because the diff housing is rigidly mounted to the chassis with an IRS, so both ends of the drivetrain are well anchored. There's essentially no fore-aft movement to be accounted for. (Those who've swapped to SRA don't have this option, because of the movement introduced when the rear end is jounced.)
:shrug:

Jim's a top wrench, and I don't really doubt him. Besides, it make sense when I think about it. But I've never heard this possibility mentioned by anyone else. Has anybody ever done this to avoid having to score a new driveshaft?

Thanks,

T-

:thumbsup:

 

[99COBRA2881]

I havent done the swap you described but I do have some measurements for you from one of my old posts.

Measurements were taken from center of u-joint to center of u-joint on both driveshafts.
99 stock d/s length 44.5"
99 T56 aluminum d/s length 44 1/8"

*This measurement on the aluminum d/s is very very close, but I wont say its exact. I was laying under the car with the left rear up on a jackstand. Although, I did measure twice to double check the length.

http://www.svtperformance.com/forums/showthread.php?t=237221&highlight=driveshaft

I would say that you might not even need to take off an inch, I'd start with 1/2", see how it fits and go from there. You can always cut more off if need be.

hth

 

[viperbluelx]

I have the D&D standard T56 and I like the 1st gear ratio a lot, I just wish I had the .50 6th gear of the Viper spec. I have a 4.10 gear and I'm still turning like 2,800 in 6th running 80, it's just like 5th gear in a T45. BTW, I've been 6.95 in the 1/8th with a 1.400 60ft on the standard T56 and it still hasn't flinched. I think the Viper spec is overkill in most cases.

 

[cobraracer46]

I've been thinking about switching over to a T56 when I put the car in the air for a bunch of other upgrades - hopefully in the near future.

If I switch to a T56, I'm leaning toward the 00R-spec tranny, because I just don't think the 2.66 first gear in the Viper-spec unit is enough for a 3.73 rear end - at least, not if I want to do my part to keep my favorite tire companies in business, LOL. Also, I prefer the 00R-spec .80 and .62 overdrive gears to the .74 and .50 ratios. Any opinions on this?
:shrug:


T-

I'm going with 373 gears and once I swap over to a T56, with out a doubt,
the 00R box will be my choice. By the way, I dealt with D&D performance in the past and I highly recommend them!

 

[Sanchez]

If I switch to a T56, I'm leaning toward the 00R-spec tranny, because I just don't think the 2.66 first gear in the Viper-spec unit is enough for a 3.73 rear end

It's not. To preserve your current total first gear ratio, you'd need 4.56's out back with the 2.66 first gear.

Also, I prefer the 00R-spec .80 and .62 overdrive gears to the .74 and .50 ratios. Any opinions on this?

http://www.svtoa-atlanta.org/cgi-bin/trans.cgi

The 00R won't really give you any particular advantage over your stock tranny. You'll lose some torque in first gear, and you'll save ~200 rpms at 80 mph by having a 6th gear slightly taller than your current 5th.

 

[viperbluelx]

This is the gear ratios in the standard T56 from D&D and that's what I've got, I've never seen them refer to it at 00R??? 2.97/2.07/1.43/1.00/.80/.62

 

[Taz]

Thanks for all the feedback, guys. 2881, it looks like your measurements support my buddy Jim's opinion. In fact now that you mention it, he may have said 1/2", but it's been a while since we talked about it. Special thanks for that info.
:thumbsup:

Anyway, I'll be one happy camper if I can keep my PST. YES! Mark at PST built me a custom DS with forged aluminum yoke caps, so it ran even more than most of PST's carbon fiber units, which aren't cheap to start with, so I'd hate to have to bite the bullet for another one.

This is the gear ratios in the standard T56 from D&D and that's what I've got, I've never seen them refer to it at 00R??? 2.97/2.07/1.43/1.00/.80/.62

Although D&D may not refer to them as such, those ratios are 00R-spec.

The Terminator-spec ratios run 2.66 - 1.78 - 1.3 - 1.0 - 0.80 - 0.62

And, of course, the Viper-spec ratios are the same as the Terminators through 4th, with 5th and 6th ratios that are 0.74 and 0.50 .

That 2.66 first may be fine for a Viper that's got more torque than a Southern Pacific locomotive, but I think it's the primary reason the terminators aren't quite the thrill that they might be from a dig - at least not without some major aftermarket massaging.
:shrug:

Okay, here's where I'm at with this whole thing - I think I've had the 3.73 ring and pinion set since last June or July, but they're still just sitting in the box, because I haven't felt any urgency about installing them. Since I added the twin screw, I like the stock 3.27 gears with the TR3650's stump-puller 3.37 1st a LOT.
:burnout:

However, now we're (hopefully) finally getting around to building the rear end and throwing the gears in, but I'm certainly not looking for more torque multiplication in 1st. That's partly why I started thinking again about migrating to a T56. It turns out that a 2.97 first in the T56, mated with the 3.73 gears, will give me almost exactly the same first gear pull that I have now. That's exactly what I want.

As an added bonus, I'd get that 0.80 5th gear that will allow me to pull all the way to redline in 5th, if I were so inclined. (The Ford 155 mph speed governor is long gone.) I must confess that I like going really, really, really fast (you'll probably see my name on the Darwin Awards someday), so being rev-limited at 180 mph definitely appeals to me. That means I'll actually be able to justify those "Y" speed rated S03's.
:-D

Okay, I'm pretty sure I've convinced myself to do this thing. But if the GF gives me any crap about it, I'll blame it on you all. Hahahahaha!!!
;-)

Happy trails,

T-

:thumbsup:

 

[blown01cobra]

Do It Do It!!!

 

[REX-RACER]

Thanks for all the feedback, guys. 2881, it looks like your measurements support my buddy Jim's opinion. In fact now that you mention it, he may have said 1/2", but it's been a while since we talked about it. Special thanks for that info.
:thumbsup:

Anyway, I'll be one happy camper if I can keep my PST. YES! Mark at PST built me a custom DS with forged aluminum yoke caps, so it ran even more than most of PST's carbon fiber units, which aren't cheap to start with, so I'd hate to have to bite the bullet for another one.




Although D&D may not refer to them as such, those ratios are 00R-spec.

The Terminator-spec ratios run 2.66 - 1.78 - 1.3 - 1.0 - 0.80 - 0.62

And, of course, the Viper-spec ratios are the same as the Terminators through 4th, with 5th and 6th ratios that are 0.74 and 0.50 .

That 2.66 first may be fine for a Viper that's got more torque than a Southern Pacific locomotive, but I think it's the primary reason the terminators aren't quite the thrill that they might be from a dig - at least not without some major aftermarket massaging.
:shrug:

Okay, here's where I'm at with this whole thing - I think I've had the 3.73 ring and pinion set since last June or July, but they're still just sitting in the box, because I haven't felt any urgency about installing them. Since I added the twin screw, I like the stock 3.27 gears with the TR3650's stump-puller 3.37 1st a LOT.
:burnout:

However, now we're (hopefully) finally getting around to building the rear end and throwing the gears in, but I'm certainly not looking for more torque multiplication in 1st. That's partly why I started thinking again about migrating to a T56. It turns out that a 2.97 first in the T56, mated with the 3.73 gears, will give me almost exactly the same first gear pull that I have now. That's exactly what I want.

As an added bonus, I'd get that 0.80 5th gear that will allow me to pull all the way to redline in 5th, if I were so inclined. (The Ford 155 mph speed governor is long gone.) I must confess that I like going really, really, really fast (you'll probably see my name on the Darwin Awards someday), so being rev-limited at 180 mph definitely appeals to me. That means I'll actually be able to justify those "Y" speed rated S03's.
:-D

Okay, I'm pretty sure I've convinced myself to do this thing. But if the GF gives me any crap about it, I'll blame it on you all. Hahahahaha!!!
;-)

Happy trails,

T-

:thumbsup:

Taz, your an animal man ( pun intended )! :thumbsup: :beer:

I can't wait to hear how this turns out. T56 has been in my long term future plans every since I got my Cobra. I so hate the 3650! :nonono: I'm glad you parsed out all that info on the d/s. I've been thinkin' about going to an aluminum d/s but have been hesitant about it since I figured I'd have to get a whole new one after a tranny swap, but it appears that this not the case after all!

BTW, what clutch are you planning on running w/ this set up?

Keep us posted! :burnout:

 

[Taz]

Taz, your an animal man ( pun intended )! :thumbsup: :beer:

I can't wait to hear how this turns out. T56 has been in my long term future plans every since I got my Cobra. I so hate the 3650! :nonono: I'm glad you parsed out all that info on the d/s. I've been thinkin' about going to an aluminum d/s but have been hesitant about it since I figured I'd have to get a whole new one after a tranny swap, but it appears that this not the case after all!

BTW, what clutch are you planning on running w/ this set up?

Keep us posted! :burnout:

I have a Ford Racing # M-7060-D46 setup w/ the clutch, PP, and aluminum FW. It's still sitting in my garage with a pile of other stuff I bought last year and haven't installed.

I'm such a sloth.

:nonono:

T-

 

[REX-RACER]

I have a Ford Racing # M-7060-D46 setup w/ the clutch, PP, and aluminum FW. It's still sitting in my garage with a pile of other stuff I bought last year and haven't installed.

I'm such a sloth.

:nonono:

T-

I defeinitely feel you on that sloth thing, I have over $3k worth of suspension parts that have been sitting next to my car in the garage for over 14 months! This year that's stuff is getting on the car and the car is getting on the track if I have break my bank and the car to do it!!! :mj:



Anyways, for you guys that have done or are doing the T56, how did you set up the reverse lock-out? I've heard a couple of different routes on this and was just wondering what the commonly accepted method is these days? :shrug:

 

[99COBRA2881]

Ive got the both hands switch installed.

The pigtail for Reverse from GM is on my T56 trans, I just have yet to wire it in to a separate switch. Its been like that for well over a year now. The both hands method works just fine for now.

 

[99SVTAddict]

Ive got the both hands switch installed.

:lol:

Same here. I just put some muscle into it and it works just fine.
No one drives my car but me so it's good enough.

 

[REX-RACER]

:lol:

Same here. I just put some muscle into it and it works just fine.
No one drives my car but me so it's good enough.

"Both hands switch"

Is that the same as the "Gorilla shift"? :lol: