Technical Flathead 11" clutch??

OK, so I came to the realization yesterday that I messed up. I have an 8ba flatty that I am putting a T5 tranny to, hopefully soon. As I am wading through the pilot bushing, throwout bearing, etc issue I realize I have the wrong flywheel.

I have a 9" flywheel, it was a dog dish one and I paid to have the dog dish taken off, I bought a new 9" pressure plate, had the machine shop balance it all. Then as I realize the 9" isn't for a an 8ba, it is for a pre-49 era flatty. Therefore, my starter won't engage the ring gear.

As I start to get upset about the waste of money, I remember I have another flywheel. I measure it and I have the pressure plate and clutch disk - it is an 11". So, I have read the springs are stiff for heavy trucks, but then I read a couple of people have put them in and have no issue.

This is going into a 30 model A coupe with no fenders or hood, so pretty light. The engine is a mild build, EAB heads, stock crank, dual 97's, Edelbrock intake, junior 400 (yes, I know, maybe too much cam for this street engine - I don't want to rehash my cam choice).

So... what do you think run a 11" or find a 10" 8ba flywheel? I would like to run what I have, but I don't want to go through all of this work to have a heavy clutch pedal that makes me not want to drive the car. I want to have a good ride that I can enjoy. I am not racing and not doing shows, this is a car that I can drive around and hammer on a little bit. I also don't think I can find a place that would want to redrill the flywheel for a 10" PP, I think I am better off trying to find a 10" if I go that route.

 

Drill the later flywheel for the 9" clutch.

I thought all the flywheels with the collar where for the pre 49, so it probably wouldn't have fit your 8ba anyway.

 

/\/\/\/\/\/\ X2!

 

A friend of mine replaces the springs in the 11" with the lighter car ones. He likes the lighter pedal and 11"ers are eeeasy to find. (around here anyway)

 

Since we're talking clutches here I have seen two different styles one with throw out bearing adjusters and ones without. What's better and does the ones without adjust a different way. I'm talking about the three fingers that touch throw bearing. Different years maybe?? I hope this helps everyone. Sorry but I'm not trying to hijack here

 

You would be better off either finding a 10" flywheel from a light truck , that flywheel would be much lighter than the 11" . the 11" flywheel is much thicker. or the perfect choice would be a passenger car flywheel and that will be a 9 1/2 clutch. and of coarse it would be much easy to disengage. these would be all 8ba 49 to 53 .

 

Last year I installed an 11". Was worried the pressure plate would be too stiff so I had it the pressure plate rebuilt with lighter springs. Worked like charm.

 

Oh! Like your coupe too.

 

Either install lighter springs or have your flywheel drilled for the 10 inch pressure plate.

 

OK, how do I install lighter springs on the 11" pressure plate? I am definitely interested in this. Would Mac's sell the springs or who? I can't find a "clutch" shop around here, but maybe I don't know what to look for. I am in the Virginia, DC, Maryland area. The 9" setup is new, the 11" setup is older. How do inspect the 11" pressure plate because it actually looks like it is in great shape, but the flywheel looks like it needs to be turned.

Here is the 9" setup that has the ring OD around 13-1/4".

Here is the 11" setup with a ring gear OD of 14-1/4" to 14-1/2"

 

ANY machine shop can do that job. (Indexing wheel and a standard milling machine; can even index on a good drill press)
IF you do this, be sure they counter bore the holes for the special pressure plate bolts.
(long shoulder) Take them a bolt, plus: have them duplicate the dimensions of the original bolt bores...
This is a standard machine operation, NOT expressly 'automotive'.

 

What bell housing are you using?

 

I've also heard of taking the center spring out of each set of 3 on each 1/3rd of the pressure plate(turn 9 springs into 6 & reduce the pressure. ) It's not a heavy duty truck ; with a light car it should be OK, both as far as your left leg & the clutch function are concerned, just use the same strength springs as your 9"pressure plate.

 

I am using the car bell housing, from around 50 I guess. I am using the Modern Driveline adapter as well.

 

Call Fort Wayne clutch.None better for clutch and p-plate work.