Let's talk Transmissions

[Whodeeny]

Originally Posted by desgros@vtlink.

Grubby - Exactly. When I spoke with Peter about my Slabside that is what I was told.


John
ERA #3010 Slabside 289 BRG

That is what Peter told me too when I asked him about a 6 speed in ERA821. He said they won't fit. I ended up with a TKO 5 speed with an .821 OD and a 3.50 rear end. The car has a 427FE putting out about 500HP. It works well although I very rarely get into 5th gear. I have less than 1000 miles on it so far having just got it finished and licensed last summer.
BD

[fastd]

My ideal is to set up the gearing so that you could get to 50 mph in first gear at say 5000 rpm (my engine tops out around 6300). In top gear you’d like to be around 2000 rpm at 80 or so.

[PCW]

Thanks for all your thoughts! I will reach out to Peter as well for his opinion...

Craig

[eschaider]

Originally Posted by fastd

My ideal is to set up the gearing so that you could get to 50 mph in first gear at say 5000 rpm (my engine tops out around 6300). In top gear you’d like to be around 2000 rpm at 80 or so.

Check out the Second Strike Gearing Calculator <= clickable. If you use a 0.82 OD TKO 600, a tall 275 x 65 x 15 rear tire (30 inch diameter) you will only be able to get to 69 MPH at 2000 rpm w/ a 2.92 R&P. 80 mph is measurably higher and louder. If you use a more traditional 295 x 50 x 15 tire 2000 rpm will only be 64 MPH! 80 mph with this tire is 2500 rpm.

Don't forget your side pipe exit is only about 24 inches from your left ear. If you are driving on the highway this would be an example of an uncomfortable experience. Ear plugs would help but a lower engine rpm by about six to eight hundred rpm or so would be much better.

A T-56 with a 2.66 first gear will give you approximately a 1700 rpm engine speed at 80 mph. Sound pressure on your eardrum at 2000+ engine rpm for an extended highway drive will diminish your hearing both immediately after the ride and longer term also, not to mention the potential for tinnitus.

The question for the owner / builder is how much pain do you want to associate with the driving of your car. After a while you will be wondering why you didn't think far enough ahead to get under car exhausts.


Ed

[6TNCRZY]

I have a TKO600 .82 with the carbon fiber synchros and internal shift modifications done by Liberty transmissions ready to go when I get my ERA FIA. I think that is the best setup. Toploaders are heavy, no overdrive and external linkage, the T56 would be a very tight fit in a 289 tunnel, plus you have an extra 50 lbs and less ground clearance.

[LMH]

I'll probably take heat for this but I'm a huge fan of T-5's. There isn't a better transmission out there and a built unit is way stronger than it needs to be. There's also lots of setups and parts for the T-5. The issue is when used in a small block Cobra, the shifter is in the wrong location. There are ways around that though due to T-5's being so modular but you really have to know what you're doing to get it right. I was told someone was making a tailshaft housing with the correct shifter location but I haven't personally seen it.
Larry

[peterpjb]

Originally Posted by PCW

Working with Peter to finalize my build cost and I have most of my build nailed down. Still deciding on the engine builder, but the car will be a FIA 289 with either a 331 or 363 ci with an 8 stack carb weber set up, targeting approx. 425-450 HP.

Thanks Craig

a FIA 289 isn’t any more a FIA 289 but a FIA 331 or a FIA 363, right?

so the question what transmission is to use in a FIA 289 is easy: T10 L

[Kit Coyle]

I think it helps to know how you will use the car most of the time. I am the
second owner of mine so I have what the original owner decided, which is
the Tremec TKO with the .68 overdrive and a 3:31 rear. Most of my driving is
on fast curvy country roads where even 4th gear is rarely used. The 5th OD
gear is hardly ever used, but if I end up on a freeway for any length of time
it is nice to be just a bit over 2000RPM @ 80+ MPH. Nice, and quiet enough
to have a conversation. Bottom line; I have a nice 4 speed with a very
occasional freeway OD gear. Now if I were picking my transmission I would
probably go for the Liberty modified TKO with the .82 OD.

[Anthony]

Originally Posted by 6TNCRZY

Toploaders are heavy, no overdrive and external linkage,

Well, you can get an all aluminum toploader.

[67sn8ke]

I have a TKO 600 modified from Liberty Gears and it shifts GREAT!! The cost was around $2850.00,but I believe they went up a little since I bought mine.

[LMH]

Here you go! T10B-1
Larry

[xb-60]

Originally Posted by fastd

OP: Mine is the T56 Magnum with 2.66 first, .80 5th and .63 6th.

To xb-60, what ratio is the 1st gear on your toploader? the close ratio has a 2.32 first gear and the wide has 2.78. I generally agree with your speed is really like a 5 speed given your gearing; but I would still recommend a five speed; your 2.92 is a nice 60-70 gear but not really a cruise gear; if you a doing 75 on the highway for a decent stretch then a 5th gear would be nice.

Reply to fastd....

It's a WR Toploader, so the 1st gear ratio is 2.78
So, in 1st gear, 1000rpm translates to 10mph (more than acceptable for my requirements).
Again, in 1st gear, 6000rpm translates to 60mph (again, perfectly happy with that).
In top 4th gear, 2500rpm gives me 70mph

(Tyres are 275/60x15)

I don't need a five speed gearbox, and which five and six speed 'boxes were available in the early '60s anyway?

Cheers!
Glen

[xb-60]

Originally Posted by 6TNCRZY

....Toploaders are heavy.....

Heavy? Compared to what?
Toploaders and TKO600 are almost identical in weight. Difference would be a couple of pounds at the most

[Unique427]

Originally Posted by Anthony

Well, you can get an all aluminum toploader.

I've got a 1-3/8" input aluminum Toploader from David Kee (DKT).
It's about 25 lbs. lighter then the cast iron unit.

Also replaced the plastic Hurst shifter bushings with machined tool steel
units from Paul Cangialosi at 5speeds.com. These have kept the shift
alignment perfect with zero slop. Machined with the exact same
dimensions as Hurst bushings and will not crack or deform.

[joyridin']

I have a T56 in mine with 3.70 rear gears. It runs about 1900 RPM at 70 mph with a .57 6th gear.

I love it, but I would never use it with a carb set-up.

[fastd]

Originally Posted by joyridin'

I have a T56 in mine with 3.70 rear gears. It runs about 1900 RPM at 70 mph with a .57 6th gear.

I love it, but I would never use it with a carb set-up.

What do carbs have to do with it?

[eschaider]

Originally Posted by xb-60

Heavy? Compared to what?
Toploaders and TKO600 are almost identical in weight. Difference would be a couple of pounds at the most

Tremec claims the TKO is a 99 lb transmission and the T-56 Magnum is a 135 lb transmission.


Ed

[FredG]

I have the TKO 600 in my car with the Roush 427 r. I appreciate having the overdrive gear when I go on the highway but I can tell you it does not shift the same as the old m-21 close-ratio I had in my 66 Vette with the competition plus shifter. The throws were short and crisp. These are a little bit longer you have to work them a tad. I miss that but I will sacrifice it for the overdrive.

[ERA 626]

I just bought a .82 Road race TKO 600 form Modern Drive Line. Its not been installed yet. Its still on my work bench. I am reading this thread and wonder how difficutt is the Liberty modification to do my self? is it worth the trouble? I have a CSX 6xxx car with a 3.54 rear gear. The motor is going to be a 650/650 shelby aluminum 482.

[blykins]

The transmissions have to be completely disassembled. The mods that are done include a surface finish enhancement on the gear cones, blocking rings are replaced, shift finger is replaced, and the thrust clearances are blueprinted. The biggest issue is the surface finish on the gear cones.