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Discussion Starter · #1 ·
Perhaps I should re-phrase....

When I build my roadster, I'm planning on a driveline of: FE engine, Top-Loader transmission (wide-ratio), that hellacious little driveshaft, back to an IRS.

Anyway. I REALLY want the Top-Loader. Don't care that it's a 4-speed. The originals had it, so I want it.

Looking at folks' build reports, it seems the selection is usually a Tremec or TKO, 5-speed.

Any real drawbacks to using the Top-Loader, other than the inherently wider gearing?

Thanks!
 

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FFCobra Captain
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Probably not a great comparison, but I had a muncie 4speed in my 1968 camaro and really wished I had a 5 speed when driving on the highway.

Nobody really sees the trans, so I dont think having a modetn trans detracts from the original appearance that you may be going for.
 

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No downside to a top loader other than the fact it's only 4 speed and you'll be turning a few more rpm's at speed.

As the previous poster mentioned, nobody ever sees or even asks about the transmission.

Bruce
 

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With a 4 spd you have to adjust your rear gearing because of the absence of an overdrive gear. Other than that, there is nothing wrong with a Toploader
 

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Had a mustang fastback with that drivetrain. Would not have changed it because it was an original 4 spd car. I considered a toploader for the FFR because if you get a good one it is bullet proof, but in the end I built my roadster with an FE and a TKO 600 because I like the FE and I like to drive the car a lot.
 

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Your thread title scared me at first. Having feelings for a tranny. Whoa?!!
 

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Any real drawbacks to using the Top-Loader, other than the inherently wider gearing?
In every automotive transmission I'm aware of (at least the ones you're going to be looking at), 4th gear is 1:1 ratio (engine rpm = driveshaft rpm). That goes for 4 speeds, 5 speeds and 6 speeds.

There are different spreads for first through third, thus the close or wide ratio discussion.

Anyway, the only thing I would be worried about on a top-loader is that mass production metallurgy wasn't nearly as good when most of those parts were made (1960s top-loader parts).

There were definately bad (weak) parts made, there were definately good parts made.

I have no idea how you would tell the difference without breaking parts. It could definately be an issue, especially behind a FE.


HTH,

Mike
 

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Twelve years ago, when i started my roadster, I built a 428 FE. Not meant to go in the early FF's. I also bought a top loader tranny. As it turned out, 2nd gear was messed up, and the cost for the new gear and rebuild was just short of a new TKO at the time. I went with the TKO.
If you go with the top loader, and the FE, you will probably need to make sure it has the larger input shaft. Also, the 1968 Mustang top loader is 26" long, 2" longer than the TKO. if you are looking at another Ford or Mercury top loader, the are 29" long, 5" longer than a TKO. With that length, if doable, you would probably need to go IRS. Also, will the shift linkage clear the frame work on the MKIV tunnel?

Rob
 

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If you are dead set on a top loader, I would get the close ratio instead of the wide. The car is so light, you don't need the lower gear first gear.
 

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Also, the 1968 Mustang top loader is 26" long, 2" longer than the TKO. if you are looking at another Ford or Mercury top loader, the are 29" long, 5" longer than a TKO. With that length, if doable, you would probably need to go IRS. Also, will the shift linkage clear the frame work on the MKIV tunnel?
Good notes and a good question on the linkage - I don't know.

And for the record - the typical GTO and Camaro T56s are 31 1/4" long, so the longer top-loader is definately out toward "requires IRS" length.

Mike
 

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Well, it likely won't make much difference - until you run against a guy with a 5/6 speed.

I had a '66 Mustang 200 CID six, and the bosses son had no problem dusting me off in his 350 Camaro - two car lengths in our impromptu 1/4 mile contests. It doesn't take many to get the idea.

I switched from the Explodomatic manual 3 speed to a top loader wide ratio. I cut a car length off just by adding one more gear.

You get to run thru the torque curve again with another gear, and it makes a difference. Take the extreme case, pulling an 85,000 pound semi with a Cummins. Not even 350 hp, but having more gears means getting up to speed more quickly - you have the bulk of the torque curve available in an appropriate gear selection more often. Not slowly winding up from the bottom end.

On the other end of the drivetrain, you get to choose a final drive ratio that complements your first gear to provide the optimum take off - and still keep the final rpms under 2,200 at cruise on the highway. If long distance driving and gas mileage have any priority in the build, getting 3-5 mpg more on a trip should rank right up there.

I loved my top loader, but not that much. Depends on how you intend to use the car, or whether it's more to have what you did before.
 

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Official OLD GUY
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best of both worlds

{quote} " In every automotive transmission I'm aware of (at least the ones you're going to be looking at), 4th gear is 1:1 ratio ". <- same as your original Top-loader.

Why not just get the 5 speed for the long cruise factor and drive around town using the first four, saving 5th for the highway . . . put a 4 speed shift ball on the shifter and never mention it to anyone that you have an OD available. Great "vintage" looks, modern gas mileage (as good as you can get with an FE), the functionality of the first four around town (get the close ratio), OD available when you need it at 80 mph.

Just my 2¢

Doc :beerchug:
 

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I had no drawbacks with my fe/toploader in my 67 stang. Until I put 370's in the rear .It raised the cruise rpm just enough to cut the mileage in 1/2. Old school Hurst shifter , nice , couple of carbs , nice , dang I miss that car ! The originals used a 3.54 rear , top speed is aero limited , so if you keep to under7k rpm you'll be fine.FYI someone here has(had) a nice 427 tunnelport with a toploader finished car for sale reasonable . Bob
 

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FFCobra Craftsman
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Don't know anything about Toploaders specifically but I think you will be fine w/ 4 gears. I'd run a 308 or 273 rear gear w/ the wide ratio version so you have a useable 1st gear. And I'd build the big block w/ a mild cam so it works at just off idle and has plenty of torque to work w/ the somewhat wider than currently usual gap between gears. As reference my car w/ the 327 1st gear and 308 diff has a good first gear. It could be just a little taller and be OK(273 diff) especially w/ your big block.HTH
 

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Discussion Starter · #17 ·
Well, this thread is just another example of my lack of wrenching experience. Guess I just liked the "idea" of having a Top Loader. Now, I DO like the idea of a vintage 4-speed black shift knob, with the "secret" top gear.

Thanks all!
 

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T56 all the way

My dad had wanted the old school top loader as well but I convinced to go with a 6 speed T-56.... He got hold of Shafi at Keisler engineering and they built a custom unit that's about three inches shorter then the standard T-56 and good for 700 HP it also resolves the short drive shaft issue...Good luck...Sean K
 
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