1970 T/A clutch assembly
 

I haven't purchased a new clutch and pressure plate assembly in awhile, but now I need one for the "70 T/A. and looking for input from others on what is the best ones available these days. Car is mostly stock and driven as a cruiser mostly and not raced. Hopefully a USA made assembly is still available. TIA. Also need a new clutch fork.

I've been putting Luk brand clutched in my cars. They are inexpensive and work just fine for stock applications.

LUK is an OEM supplier. I have used them exclusively for a long time now. Highly recommend

Im a McLeod user,have them in all 3 of my cars.Get a good organic disc,stay away from any metal or Kevlar IMO.Tom

Very interesting as I had never heard of the Luk units before and I see they come with a plastic throw out bearing which seems odd as that wasn't what they came with new. I was thinking of the McLoud unit as they have them rated by engine horse power and I don't see anything pertaining to HP on the Luks. Picking a clutch set seemed so simple in the old days as there were not so many choices.

Plastic throw out bearing must be a new thing as I have never encountered that.

LUK is an OEM supplier. They are direct factory replacements not necessarily meant to be for the 500hp engine. Nice feel with a firm not hard pedal. It’s not a racing clutch it’s a driving one. https://www.summitracing.com/parts/l...bird/year/1970

So I decided on the Luk clutch kit # 04-049 which has the 11" clutch disc and did the check fit option on the Summit Racing site and it says that it does not fit the 1970 Pontiac T/A. Then I tried the kit with the 10 !/2" clutch disc and checked for fitment and Summit also says it does not fit the T/A. Am I missing something here? I also looked up the McLoud clutch kit # 75124 which also looked pretty good but once again Summit fitment check says it does not fit the 1970 T/A. I am guessing that since it is not a Chevy I am asking about, that Summit has no clue what fits a Pontiac. Has anyone else had this issue with Summit. I picked Summit as they have a warehouse near by.

Does the engine have a 11" flywheel pattern bolt holes? Some flywheels are just for 10.5 discs?


:confused:

Yes. The clutch assembly I am replacing has an 11" disc. The flywheel is drilled with 2 sets of holes. one 11" and the other is 10 1/2 " Not sure what the car came with from the factory as thie clutch assembly that was in it is aftermarket, but i can't tell who made it.

Looks like the 1970 T/A came with the 10.5 " clutch. Now another option is do I use the 10.5 or the 11" clutch if either will fit?

I’m certain that the number I posted is correct and I have used it in my own 70. 04-021

OE 1970/400 was 10.4"
I believe that the 11" setup came with the 455's.

Try looking it up for a GTO with same drivetrain.

The disc doesn't know what it is for. If the flywheel will take a 11" disc, use that. Along with the proper pressure plate for it. The throw out bearing to match the pressure plate.


:)

OK. I will just order the 11" set up from Luk and disregard what Summit says as to fitment as they don't seem to know anything about it and it is probably just a way to cover their rears. Thanks for all the advice as it has been very helpful.

I had no luck with Luk as they only offer the 11" clutch disc with a 26 spline which won't work on the M-21. That got me thinking about the flywheel as it is drilled for both 10 1/2 and 11 inch disc but I noticed that the outer set on holes go through the inner edge of the ring gear which seemed odd. Flywheel has a PN 9779263 with a B180 date code so I believe it is original to the car but It seems that the flywheel was drilled to accommodate the 11" disc later in time which would explain the ring gear being drilled into. The question I have regards the integrity of the flywheel as the holes that I believe were added later are directly outside of the original holes for the 10 1/2 " disc. To me, the hole being rather close together and the partial drilling through the inside edge of the ring gear makes me question if this flywheel is safe to use or am I taking a big risk. I did have the flywheel surfaced at a local machine shop and they did not comment on it having issues but maybe that is not their job. What do you all think?

Replace it.

Thanks. Any ideas on a good replacement flywheel? I never have had to go down this road in the past so it is all new to me. Thanks again!

HAYS Street/Strip 10.5