I have a TKO 600 in my LX, and a Viper spec T-56 in my Cobra. Both are like swinging an axe to shift. Both cars also have 3.55's in the rear, I rarely get to use 6th in the Cobra, it is crazy high. TKO is a bit cheaper, lighter, and unless you are running 4.10-4.56 gears I can't imagine the T-56 being worth it.
T56 or tko600? And is the install as simple as it seems? (Foxbody)
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I've had the 3550, TKO, and 4 T56s.
If you're going big power, you'll want the T56. Yeah, I'll go with gear grabber's ~650+ as a rough guess at the crossover. That said, a TKO *can* handle more than it's rated for. I made 762 to the tire with one and did not have any problems. I didn't test it on slicks, though.
IMO, there are 2 big reasons to go T56: First is the power. There are 1200hp capable T56 units out there. They are using high-end gears from G-force, but they can be put directly into a standard T56. Second, the 0.50:1 6th gear. I disagree wholeheartedly with the sentiment that it's too much gear. That's bogus. When you go to a 3.73 or 4.10 gear, 6th gear is very useful on the highway. So, if you want the rear gear and you want a comfortable highway gear, then the .50 6th is a good match.
Plenty of the T56s, like the 03-04 Cobra T56s, come with .63 6th gear ratios, which IMO defeats the purpose of having that extra gear. The T5 and TKO have 0.68 5th gears. That's only a few percent difference unless you go to the .5:1 6th gear T56. The only way I can understand this play is if you really need that .83 5th gear for some reason, but I think that's a very small minority of folks who are racing into 5th. A 10-spline input also defeats the purpose too. If you get a 10-spline T56 with the .63 6th gear, you have limited yourself to less power than a TKO is good for, and the overdrive is not significantly different. That would be a waste of money, IMO.
Last, I'm a little confused about the shifting differences. My 3550 shifted very nicely. The TKO, however, was notchy as hell. I've heard of issues with the shift rails in the TKOs. All that said, all 4 of my T56s shifted wonderfully.
The bellhousing shim might not be necessary with a single disc clutch. However, if you go with the McLeod twin disc, you'll need one. No big deal, really. It's a cheap part made by quicktime, I believe. If you get this far, send me or raceoholic a message and we'll direct you to the right part.
If you're going big power, you'll want the T56. Yeah, I'll go with gear grabber's ~650+ as a rough guess at the crossover. That said, a TKO *can* handle more than it's rated for. I made 762 to the tire with one and did not have any problems. I didn't test it on slicks, though.
IMO, there are 2 big reasons to go T56: First is the power. There are 1200hp capable T56 units out there. They are using high-end gears from G-force, but they can be put directly into a standard T56. Second, the 0.50:1 6th gear. I disagree wholeheartedly with the sentiment that it's too much gear. That's bogus. When you go to a 3.73 or 4.10 gear, 6th gear is very useful on the highway. So, if you want the rear gear and you want a comfortable highway gear, then the .50 6th is a good match.
Plenty of the T56s, like the 03-04 Cobra T56s, come with .63 6th gear ratios, which IMO defeats the purpose of having that extra gear. The T5 and TKO have 0.68 5th gears. That's only a few percent difference unless you go to the .5:1 6th gear T56. The only way I can understand this play is if you really need that .83 5th gear for some reason, but I think that's a very small minority of folks who are racing into 5th. A 10-spline input also defeats the purpose too. If you get a 10-spline T56 with the .63 6th gear, you have limited yourself to less power than a TKO is good for, and the overdrive is not significantly different. That would be a waste of money, IMO.
Last, I'm a little confused about the shifting differences. My 3550 shifted very nicely. The TKO, however, was notchy as hell. I've heard of issues with the shift rails in the TKOs. All that said, all 4 of my T56s shifted wonderfully.
The bellhousing shim might not be necessary with a single disc clutch. However, if you go with the McLeod twin disc, you'll need one. No big deal, really. It's a cheap part made by quicktime, I believe. If you get this far, send me or raceoholic a message and we'll direct you to the right part.
I am currently running a 3550 behind a windsor and I believe I have 3.73’s, and I like it a lot. I think the overdrive is plenty whatever ratio it is. I want that extra gear between 4th and od. There is a definite gap there in comparison to the first three shifts. My car is all street but I might try a road course track day if I get it just right. I daily drive my car very hard. I am shifting up and down ALL the time. If my car is moving it is in gear and I am off the clutch pedal. Cobra T56 sounds perfect. My windsor isn’t making a ton but it’s a ton of fun! Haha!
WhiteCobra95
Mod Dude
- May 2, 2006
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G-force offers a replacement / high capacity case for their T5s. I've never actually found anyone who's run it to get feedback. Their T5 with the new case is a hefty price jump and it seems like it keeps going up in price each year. However, if all you have to do is replace the clutch to match the input shaft splines and everything else goes back in place, it's still probably cheaper than a T56 swap.
http://www.jegs.com/i/G-Force-Transmissions/468/GFT5072/10002/-1
http://www.jegs.com/i/G-Force-Transmissions/468/GFT5-SNGF/10002/-1
http://www.jegs.com/i/G-Force-Transmissions/468/GFT5072/10002/-1
http://www.jegs.com/i/G-Force-Transmissions/468/GFT5-SNGF/10002/-1
- Mar 2, 2015
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That case has been added to my wish list. Ive been building t5s for years and never knew there was a strtinger case available that cheap. The average cost to rebuild and upgrade one is pretty cheap....if it can be built for less than 1k to hold 600ft tq it seems like a better option ( cost wise ). Could even build a couple and sell them for t56 swap money.
My father n law has a straight cut, dog ringed g force t5 in their case. It has held up well so far.
Joe
When I build that all out car I will be looking for an all out gearbox to match. Straight cut gears sound like an engine all by themselves! Every REAL racing video I have ever seen has that straight cut gear whine. Someday I will drive a car with one of those transmissions.
You sure? If it's race-only, I gotcha, but this would get old on the street:
View: https://www.youtube.com/watch?time_continue=155&v=8QZezP02Imc
View: https://www.youtube.com/watch?time_continue=155&v=8QZezP02Imc
Yeah! That’s it! Like I said it would be my all out no compromises car. I wouldn’t daily something like that but I would drive it once in a while on the street! Or maybe even just track days.
T56 seems like the ticket. Only thing is i rarely see any highway action...mainly alot of country/rural roads, but i suppose the extra gear doesnt hurt being there. Not sure what rear gear id go with yet...i know with the t5 i hate my 3.73s...1st and 2nd are basically useless...What kind of price for all the parts and a good clutch for the street? Can i still use my factory speedometer? The shimming makes me a little nervous ad ive never installed one before and dont want to mess up something so expensive but ill read ALOT before tackling it like i always do.
I'd guess any T56 magnum setup with a twin disc clutch is going to cost about $6000 or so.
Browse D&D motorsports website. I don't think their prices are the best, but it's a good place to start browsing and learning.
There are a lot of factors that go into the gears.
Like where does the car make power?
I wouldn't let 5th or 6th gear decide anything. Both the tko and the t56 have generous over drives.
With the wrong rear gear and a t56 I could see the possibility of making 6th gear completely useless on a pushrod engine that makes no power at 2000rpm.
With as much power as you want to make, you are always going to have a traction problem. That's not going to change because you 3.27 gears.
Tires and driving are likely the only fix.
Browse D&D motorsports website. I don't think their prices are the best, but it's a good place to start browsing and learning.
There are a lot of factors that go into the gears.
Like where does the car make power?
I wouldn't let 5th or 6th gear decide anything. Both the tko and the t56 have generous over drives.
With the wrong rear gear and a t56 I could see the possibility of making 6th gear completely useless on a pushrod engine that makes no power at 2000rpm.
With as much power as you want to make, you are always going to have a traction problem. That's not going to change because you 3.27 gears.
Tires and driving are likely the only fix.
I have to find out definitively what rear gear ratio I am running. When I bought the rear I was told 3.55’s But first is a blip and if the car is moving you don’t need it. The trans is 3550 and at 2500 rpm in fifth the gps says just over 70 mph with 225/50r17’s. So I think I have 3.73’s. The car moves pretty well though and I’ve been having a lot of fun with it. I rev it up and dump on occasion and it spins ‘em just fine. But could I have even more fun?
I had forgotten about the .5 OD variant. That would be a nice feature.
You mentioned that 3.73s were useless in 1st and 2nd gear. You might consider a D&D viperspec. I don't know if the newer transmissions are still made with these ratios, but the old viperspec T56s has a 2.66 1st and a 1.78 2nd gear. Your T5 has a 3.35 1st, and a 1.99 2nd (1.93 depending on year). So, that's an over 20% drop in 1st and over 10% in 2nd, and you still get the 0.50 6th gear! The only way to do a T56 Magnum with a 0.50 6th is with a 2.97 1st and a 2.1 2nd. That still makes 1st a little more friendly, but 2nd is a little less 'useable'. I personally think you should go with the T56 Mag2 listed below if you can't find an old Viperspec and if they don't offer it anymore. Here are some transmission gear ratio specs I've collected, including a lot of T56 variants. If you guys catch anything needing a correction, I'm all ears, but hopefully it helps you see what's out there.
You might save a few dollars if you buy used, but the trade off is that it's usually very hard to verify that the transmission is in good shape. Yes, you can keep the stock speedometer. Most T56s have an 8 tooth drive gear, but some of the older viperspec trannies have a 7 tooth. Online calculators can help you choose the right speedo gear, or conversely send me a message and I can give you the exact calculation.
Do not be afraid of the 1/4" shim. It took me a while to figure out, with Raceoholic's help, but being aware was the entire issue. I just didn't know that it was needed, and unfortunately neither did 2 shops that installed it for me. I brought it to the 3rd shop and when they had trouble too, they tried installing it, and bam! No more problems. Again, it was only necessary with my McLeod Twin-disc which takes up a lot more space within the bellhousing. I have a single disc spec 3+ on the 93 GT with the viperspec and no spacer was required. I must say that the twin-disc is definitely nicer, but also more costly.
I would also like to throw a company in the hat of transmission shops to talk to. I can bad mouth a dozen shops I've done business with, and can only wholeheartedly recommend 2. One of them is promotion powertrain. Walt is the owner, and Wally is his son. They are both awesome to work with. They built my custom T56 and every time I had an issue, their recommendations were on point. I would especially consider their clutch recommendations even if you choose to go with another transmission.
Chris
You might save a few dollars if you buy used, but the trade off is that it's usually very hard to verify that the transmission is in good shape. Yes, you can keep the stock speedometer. Most T56s have an 8 tooth drive gear, but some of the older viperspec trannies have a 7 tooth. Online calculators can help you choose the right speedo gear, or conversely send me a message and I can give you the exact calculation.
Do not be afraid of the 1/4" shim. It took me a while to figure out, with Raceoholic's help, but being aware was the entire issue. I just didn't know that it was needed, and unfortunately neither did 2 shops that installed it for me. I brought it to the 3rd shop and when they had trouble too, they tried installing it, and bam! No more problems. Again, it was only necessary with my McLeod Twin-disc which takes up a lot more space within the bellhousing. I have a single disc spec 3+ on the 93 GT with the viperspec and no spacer was required. I must say that the twin-disc is definitely nicer, but also more costly.
I would also like to throw a company in the hat of transmission shops to talk to. I can bad mouth a dozen shops I've done business with, and can only wholeheartedly recommend 2. One of them is promotion powertrain. Walt is the owner, and Wally is his son. They are both awesome to work with. They built my custom T56 and every time I had an issue, their recommendations were on point. I would especially consider their clutch recommendations even if you choose to go with another transmission.
Chris
It's the wrong O/D gears for me, but looks like the guy is willing to play ball, and claims/looks new to me. I'll bet he'd take $4,500 and I think you'd be coming out ahead. I don't know anything about that specific clutch, though. http://www.yellowbullet.com/forum/showthread.php?t=2419122
Yeah, I'm not really sure on that one. I run an aluminum flywheel on the '91, but that's only to offset the weight, to some degree, of the twin disc. It feels pretty normal to me. This looks like it's super light.
In an application that is going to see some serious abuse, like powershifting or drag racing, you can actually break one with way less than 600 ft lbs if you miss on the clutch setup. Look at coyote stock cars, they dont make too much power, and definitely not much torque, and those guys were breaking TKO's left and right which was a big reason for the NMRA letting the G-force trans into the class so that if guys missed on a clutch tuneup it didnt cost them $1000-$2500 bucks in transmission parts.
Whether it is a 500 or a 600 model, the weak link in any TKO is the case, the case will flex and that is what breaks the gears, which can also lead to the case cracking. I have broken 2 TKO's with less than 600ft lbs in a 3200 lb car, about 685-700hp, naturally aspirated, both times was third gear, and both times the clutch was on the aggressive side. After 650ish horsepower, it becomes a real gamble. The T-56 magnum is a badass trans and worth the extra weight for the average guy who isnt class racing.
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