Top Loader Limits

[475fetoploader]

   Ok, I’d like to hear thoughts, opinions, experience with the Ford Top loader, regarding its strength.  What is the weakest link, can the weakest link be improved with an aftermarket component.  I know these transmissions took a beating back in the day. 60’s Drag racing punished these gearboxes, I’d rather not destroy one, but I’m going to install it, and drive the car.  It will be replaced in due time with the next best thing, but it’s going down the road a couple times first.  Thanks in advance for your input.

[Rory428]

Some information on your combination, car weight, slicks or street tires, street only, dragstrip use , 28 vs 31 spline mainshaft, 1 1/16" vs 1 3/8" input, etc. I currently am running a small input, small mainshaft wide ratio Toploader in my 4000 + pound 59 2 door sedan. Mainly a cruiser, but I have taken it to the dragstrip twice in the past year, not really fast, ran 14.0 at 97 MPH thru the mufflers with 3.50 gears. I was leaving around 2000 RPM, so not very hard launching, dumping the clutch at 6000 on slicks would obviously be pushing it. I have ran several big spline Toploaders in my old 428 CJ 70 Mach 1, with ran mid-low 12s, on slicks. I broke a 31 spline mainshaft once, and tore up 3rd gear once, but that was after years of racing and hard street duty.

[427mach1]

Call this guy, he can most likely answer any questions you have and set you up with the right parts.  https://www.4speedtoploaders.com/

[cjshaker]

Like Rory mentioned, info about the car would help a lot.

My experience racing with a big in/out toploader. 497 hp 427 in my Mach 1 at 4460#. Quite a few hard years on the street before I started drag racing it, and never had a problem, but obviously traction was a saving point with street tires. Once I started racing, I went through 2 Drag Weeks, a couple of FE Reunions and a few Test & Tunes. At that point I was running mid 12's and still had no issues with slicks and launching hard, between 4k-5k (although occasionally breaking the tires loose), but that's when I started to have an occasional issue with hitting 2nd gear, mostly due to stock type synchros and shifting at 6000+. Still never broke anything, but it was wearing the synchros quicker. That's when I changed gearing and went with the Jerico, which dropped my times down to mid 11's.

Thor (XR7 on the forum) was a good example for the limits of the toploader. He started breaking them in his Cougar pretty regularly. I think he was running in the mid 10's with it, and launching really hard, but still had a slipper clutch. He couldn't get them to last at that power and weight level. Although his car was lightened for racing, with the roll bars and added safety gear, it was still near regular weight levels for a Cougar I believe, maybe a little less.

There are no "special parts" that will stop them from breaking once you hit that point. Replacement parts are no better than stock parts, and doing "cryo" treatments and all that jazz is just trying to postpone the inevitable. Dog rings and pro-shifting etc, helps with shifts, but does nothing to add reliability from breakage. They will help save gears from tooth wear on engagement, but that's it.

Just my opinion based on what I've observed...
500 hp in a mid-weight car with slicks and a reasonable driver is about the limit before you can expect to start having problems....sooner or later.
Add power, or weight for a bigger car, and you can subtract reliability.
And like LarryK is fond of saying, some guys can break an anvil with a rubber mallet, so your mileage may vary 

[gt350hr]

 When Dyno Don ran one in the Maverick ( "pro shifted" gears from Doug Nash) he used to "spiral crack" output shafts.  This is obvious torsional twisting issues. He even had some made in 9310 but they failed too. Too much HP, weight, and traction , something has to give. Everything else lived.

[machoneman]

IIRC it was Earl Wade who told my bro' long ago at U.S. 30 dragstrip during match races with Bill Jenkins that they hardly ever lost a race with the SOHC Maverick due to Toploader tranny issues. But, it was only because they monitored the # of runs and routinely threw in a spare after x # of runs. Teardown apparently proved this to be a wise move.   

I wish that my old racing buddy Randy Migut or his bro' Ritchie were members here. Randy ran a dual-carbed SOHC in his '63 fastback mainly at Union Grove, Wi. The car must have weighted darned near 4,600 lbs. with him in it and geez, with an easy 650 hp or so, did he break a load of Toploaders!

To be clear he had huge traction issues, mainly wheel hop, that likely caused the breakage. But oddly enough, he always sheared, clean off, the input shaft right at the front of the bearing. The rest of the tranny was o.k. in every case.   

[gt350hr]

    Bob ,
        When I helped Don move from his shop back to his house , I found six or seven outputs all spiral cracked . Don just laughed and couldn't remember why he kept them. There was one new  9310 shaft left which I got from him. I think Pepe Estrada had them made. No speedo gear provision.

[475fetoploader]

Fairlane
3400 lbs
295/65/15 e.t. Street tire
4.29 spool
Big in/out top loader
Ram clutch, hopefully it slips
511 f.e. 11.5:1  solid roller, tunnel wedge, good flowing heads
I’m starting to think I should call Jerico

[Stangman]

If your using street tires I doubt your going to get any traction with a 511 CI fe you might get lucky for a while

[cjshaker]

If your using street tires I doubt your going to get any traction with a 511 CI fe you might get lucky for a while

ET Streets are nothing more than a slick with a few grooves cut in them to make them DOT legal.

You'll want to carefully consider using a Jerico on the street. It's doable, in fact that's what I run, but to most people it would definitely not be a pleasant experience. I have a high tolerance for pain. I think they do have road race sliders that would make them more street friendly, but don't know anything about them.

[475fetoploader]

Drivability isn’t a concern.  I too have a high threshold.  I was hoping to finish this stage up without a new Trans but plans were made to be broke.  Unfortunately I have a new in box tko bell housing. Maybe it would work with a Jerico?

[machoneman]

    Bob ,
        When I helped Don move from his shop back to his house , I found six or seven outputs all spiral cracked . Don just laughed and couldn't remember why he kept them. There was one new  9310 shaft left which I got from him. I think Pepe Estrada had them made. No speedo gear provision.

Very interesting as to why Randy's '63 SOHC Galaxie broke only input shafts and Dyno's car only broke output shafts. In Randy's case his ride did have huge spring wrap and wheel hop. I swear his often 11.70's would have been low 11's or maybe better had he been able to control the rear suspension. In Dyno's case, I wonder if a chassied car like his always were contributed to twisted shafts at the tail end.

Btw, I learned a hard lesson long ago about not using steel motor mounts AND a steel trans mount at the same time in a non-chassied car. Frame twisting = broken tranny cases that were plentiful until I figured that out.   

[Nightmist66]

My experience racing with a big in/out toploader. 497 hp 427 in my Mach 1 at 4460#.

You don't weigh 1000 lbs, Doug. 

Fairlane
3400 lbs
295/65/15 e.t. Street tire
4.29 spool
Big in/out top loader
Ram clutch, hopefully it slips
511 f.e. 11.5:1  solid roller, tunnel wedge, good flowing heads
I’m starting to think I should call Jerico

What is the clutch disc style/material and pressure plate?


The trans. in my car I bought off a guy a while back that had it refreshed shortly before I got it. It is pro-shifted by Liberty and has the Mopar 1 3/16" 18 spline input shaft. The gears appear to be treated. They are not polished or coated. I have access to this, but haven't tried it yet on the trans. stuff. Since I needed a different shifter location on the tail, and I liked my case a little better, I decided to swap the guts into mine. Also, when I bought it, it had no synchro on 1st. I modified it to accept a synchro. Luckily, it wasn't too hard. Anyway, The guy I bought it from said it was in a 9 sec. Fairlane. I don't know if it had a slipper clutch or not. I haven't found the limit yet with my little warmed over engine. I don't have a soft lok clutch and if I can get it to hook this year, I will try launching at 6k. I do not slip the clutch. I will note, on the street it works best to double clutch when putting around town to keep the gears happy. I would like to have faceplated gears instead because they are more durable, but I got the trans. for a bargain at the time.

[cjshaker]

My experience racing with a big in/out toploader. 497 hp 427 in my Mach 1 at 4460#.

You don't weigh 1000 lbs, Doug. 

I didn't mention the 1000 lbs of ballast in the trunk for traction?..lol
Yeah, that was supposed to be 3460.

[6667fan]

Most of those back in the day 427s weren’t pushing over 600 hp and the tq like your 511. So they could thrash those toploaders and get away with it. You can beat on yours all day on the street with spinning tires, should not be a worry. But if you are gonna put slicks on it and try to get into the 10s with it at the track, third gear and the counter shaft can start having trouble co-existing, with unpleasant results.
This does not always happen but is a proven weak point at your power level.
Jerico or a collared G Force will take much of that worry away. However, driving a Jerico on the street is not for the faint hearted. They are rude. The solution that some guys employ with street cars is a Jerico for the track and a toploader or something like that new TREMEC for the street.
Those TREMECs have a high torque rating but I don’t know anything about their track strength.