1950 ford flathead 11" pressure plate flywheel clutch old trick
 

Dropped this F series flathead truck transmission T87D-1into my hot rod and found it is way too much difficulty to depress clutch in fact almost not possible. I want to try and old trick by taking the center spring out of each of the clusters of three on the 11' truck pressure plate. I will still be running a brand new 11' truck clutch.
My question is for those who have done it, before i go to all the trouble of putting the motor and trans back into my newly painted frame and risk a problem is....Will it work and reduce the pressure enough to be tolerable? Perhaps equal to the 10" car pressure plate? I could go spend $450 on new flywheel clutch and pressure plate but i would rather take the hot rodders way if it works. PS i am already invested in a center slip drive shaft so that $250 goes out the tube as well if i switch to transmissions conversions so dont want to do that. I have read all the posts but have not seen any results for this operation. Suggestions and knowledge please.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I'll be watching this one. I have a brand new in the box 11" Ford truck clutch, so this may be a way to utilize it.

(Any of you truck guys that want a new clutch cheap could probably talk me out of it instead.)

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

You stated Hot Rod. An 11 inch clutch and pressure plate assembly is a poor setup for a high performance application. Clutch pressure is not the main issue, it is rotational mass. The large diameter slows acceleration (inertia). A 9 inch is best in a Hot Rod application, but at least a 10.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

The old T8 truck 4-speed doesn't have the best ratios and the lack of synchronizers can be a chore. The T87 is a lot better but the ratios are still for trucks. This is fine if you want a stump puller hot rod.

The 10-inch Mercury Borg & Beck clutches had the every other spring thing when new but they were for cars. The Big Long type clutch is one heavy sum beech. It would never come close to being a choice of mine for a hot rod. F3 truck maybe? Like J mentioned, the 9-inch Long type with a lightened flywheel is just the ticket for a hot rod. The 10-inch Long would be the next choice.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I’d change it out, At least you don’t have to I’ll the pan to change it.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

What are you using for a clutch pedal and linkage?

F1 pedals and a 11" clutch is not hard to push down if your geometry is stock.

Edit, I looked at the pictures. Why did you want to use that transmission in a 32 chassis for a hotrod?

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

Where is you clutch rod attached to ? How high from the center pivot point , the higher or further you go from center the more movement you get but harder push . I forgot what factory was I'm thinking 7-8 to 1 ratio . Hopefully others will chime in with the correct ratio .

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I have removed the center springs by using a cut-off wheel. You do not need to separate the pressure plate for removal.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I'm with Skidmarks . . . running that clutch and that transmission in a HotRod - well, I'm sure you can figure out how to get away with it, but why do it? There are no redeeming attributes about that combination (clutch included) that I can think of.

With that said, any 39-48 standard Ford passenger or light truck 3-speed transmission would be a better way to go - with a 10" clutch at most.

Now, I realize you've already invested in parts, driveshafts, time, fabrication, etc. . . . but maybe you need to step back and rethink this a bit? I would if it was me - even if it took longer to complete my project (due to budgetary constraints) - I know the result will be SO MUCH better.

Good luck!
B&S

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

If you are using the hole in your clutch pedal just above the bend that is way to
far out. See the picture of an F2 clutch pedal.


Bob

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

Please pardon my ignorance, but what is that transmission? A HD 3 speed outta a 40's truck?

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

If you have a healthy Flathead, clutch plate size could matter. lighter the flywheel the larger the clutch plate the better. For most of us a aluminum flywheel or lightened is counter productive. Great for race fast spin up, bad for driving.


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Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

All I can say is that I put a fresh late EAB with 11 inch clutch in my car while my 59A
was being rebuilt. This EAB (1953) was scheduled for a F6 dump truck. Big difference
no way it had the snap of the 59A it was like 'doggy' of course its meant for a truck.
I think for your application I would go 9 inch first, 2nd choice 10 inch. Back in my
oval track racing days everybody ran the 9 inch "there was a reason" for that. Plenty
of flywheels around!

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

Clutch plate and pressure plate diameter does make a difference, but in the other direction! It is the inertia, the further mass is from the centerline of the driveline the more difficult it is for it to change rpm, in this case accelerate. In a large truck this is an advantage as it assist in pulling power. In a Hot Rod application you want the smallest rotating mass possible, and because of the inertia you want the mass as close to the centerline as possible. A large diameter clutch plate & pressure plate is going to reduce acceleration. A modern example is my 2005 mustang, there is a noticeable difference switching from a steel driveshaft to an aluminum driveshaft.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

For those that are interested. The T87 is the heavy duty 3-speed. I think Ford started using them in 1948 with the first year of the bonus built pickups. They were optional in F1 but may have been standard for F2 with the 4-speed as an option. They have spur cut 1st & reverse but they are heavy duty old turds with synchronized 2nd & high. If they are run and serviced regularly, they will outlast the cab & fenders. They have a truck like ratio but not a granny like the old T8 4-speed.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

If you are trying to somehow use that juice clutch pedal as a mechanical pedal; you better weld the appropriate length ear on it in the geometrically correct place. That hole visible in pedal now is way wrong.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I have run my 49 F1 continuously for the past 46 years. About the only thing I've never touched on it is the factory heavy duty 3-speed box. I check the oil level once a year and change the oil every few years ...

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I'm with Bob, that 11" clutch really shouldn't be that hard. I think the angles of the aftermarket linkage is loosing leverage.

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

I wonder were you got the idea to use this combination in the first place. Some of my "Bright" Ideas get shot down, wen I toss them around among friends or here on the barn. And it free!!!

Re: 1950 ford flathead 11" pressure plate flywheel clutch old trick
 

If you like changing clutches out. Isn't a 10-10.5 pretty standard on a flathead hotrod. Granted pressure plate springs can be changed for more pressure.


I am by no means endorsing the transmission here for a hotrod. Separate question.




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