Clutch size question??
 

We are installing a Tremec 5sp in my sons 68 GTO.

We finally had to time to start with install of new tranny and noticed the the input shaft on the Tremec is a 26 spline. The old Munchie is a 10 spline.
No big deal except we have a Ram power grip clutch in the car with less then 300 miles on it.
Looks like we will be getting another new clutch for the car :(

We Replaced the fly wheel when we put in the 464 stroker with a Ram Billet steel, part #1557..
My question is there any big advantage to Going with a 11''clutch over the 10.5" in the car now, which we have to replace anyways.

I talked with a tech at Silver Sport transmissions this morn and he said as long as our flywheel has 12 outside out side holes...which it does.... we could go with a 11" clutch.
That sound right ?
If so will there be any issues using the stock bell housing with a
11".

Thanks

Bill

If your just driving it just replace the disc.Tom

What Tom S said X2

How much torque, and h.p.?

I have a 462cui and a 10.5" clutch.. no problem at all at about 500hp and 500 ft lbs.
With more torque I would consider the 11"... horsepower isn't a real problem for the 10.5"... (I use a Centerforce)

With the components we used on the engine the engine builder estimated at 500 hp and 600 torque....give or take.

I always like overkill. You can go with a mcleod rsx or rst dual disc 10.5 inch that will hold 1000 h.p. and the pedal is softer than a stock pedal.
The 11 " Centerforce d.f. will be at its limit with that torque. A 3 finger clutch will give your leg a work out, for street driving it stinks.
$900 for the dual disc street version mcleod but will be the last one you need for a long time.
Just think you can put up to 500 shot of nitrous and the clutch will still be okay!
I bought a dual disc clutch this past week, I was pushing thru my centerforce d.f. in 3rd gear with just a little more h.p. than you. I have a tko 600.

You have a new system in there now,why spend more money than needed UNTILL you know you need more.I run a TKO in a 3600 lb 63 434 tempest that makes just under 500 HP.Has survived 6000 RPM launches with a 10.5 Mcleod B&B and years of street driving.Change the disc and see if you need more.Now if your going to race it a lot with huge sticky tires thats a diff story.Tom

I dont know about you, but while it is out I would change if if there is a question. Pulling the tranny, scattershield out stinks, I like to do it as little as possible.
You can do it right the first time, or spend more money and time the second time.

X-2! However, I'd use a 10.5" disc with the 11" pressure plate. better clamping of the disc.

Thanks guys

Well we got the clutch out last night and it is toast.

Inside of bell housing and pressure plate was covered with black dust from the disk.
The flywheel has a burned black residue on it from the clutch.
Either we screwed up royally on setting up the clutch adjustment or the clutch couldn't handle the torque, it appears it was definitely slipping.

We set the clutch up according to the manual and we had a mechanic check out the adjustment after we got the car back on the road. Mechanic said it was good.

I drove the car quite a few times and didn't notice any slippage but then I never put the pedal to the metal and ran her hard thru all the gears. I cant speak for my son tho.

Glad now we had to pull the clutch.

WTH did we do wrong ??

Post some photo's. Make sure you have the correct ball and throw out bearing. a long ball and long bearing will keep pressure on the plate making the disc slip. You have to make sure the bearing has some freeplay in there.
Or there was too much motor for that clutch.
Now you have to get the flywheel cut again though!

Try your hardest not to rest your foot on the clutch pedal while driving, premature clutch wear, throw out bearing wear and most importantly crank thrust surface wear. Also, while idling (red lights etc.) leave the tranny in neutral (with foot off the clutch) to reduce throw out bearing wear and crank thrust surface. When you pull a motor apart you can always tell which are the manually shifted ones just by looking at the main thrust bearing. Remember while the clutch is disengaged you are essentially pushing the crank out the front of the engine (okay a little extreme, but you get the point).

http://i731.photobucket.com/albums/w...psjg6uhigy.jpg

http://i731.photobucket.com/albums/w...pszil90zeo.jpg
Residue on the flywheel does come off with a little scrubbing. Will we need to cut the fly wheel ?
Have not removed the pilot bearing yet but it appears to be toast also.

http://i731.photobucket.com/albums/w...psebz5hw3c.jpg

http://i731.photobucket.com/albums/w...pskck8lavg.jpg

Thanks all

Bill

If you go to an 11" clutch I would think about resurfacing that flywheel.......

Take some laquer thinner on a rag and see if any will come off the flywheel. I still see the cuts under the "black area". Make sure there is no stress/heat cracks in it.

Bill,

I know this is a old post but I was wondering how you liked the Ram Billet steel, part #1557 flywheel? Was there any issues with it that effected in getting the clutch adjusted correctly?
Thanks

The billet fly wheel cleaned up just fine with a little lacquer thinner. We junked the Ram Power grip clutch and went with a Mclead twin clutch disc assembly. Very happy with that combo.
The Mclead clutch takes very little leg force compared to the Ram clutch, is a lot quieter and hooks up like a hot dam !!
Back to your question.....we are very happy with the Ram flywheel and had no issues with adjusting the Mclead clutch.....so far so good :D

Bill

Thanks Bill. I am trying to decide between the Hayes and Ram Flywheels. I was looking at installing a Ram HDX 11 in clutch. I only have 360 HP and 445 ft-lbs torq unlike like your monster. Mine is only street driven but I do want it to grab well.