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Discussion Starter #1 (Edited)
Happy New Year everybody!
It's been awhile since I've posted. I haven't had much to talk about.

My 1965 GTO 389 engine is in the machine shop getting rebuilt slowly, but surely, which suits me just fine since I don't want to swap out engines until spring anyway.

My topic is clutches. I am starting to accumulate pieces that will be used on my rebuilt numbers-matching engine, such as H.O. exhaust manifolds, and one of the other items I will change on my car with the engine changeover will be the clutch.

Now my engine is getting a relatively stock/street makeover. I had to take some extra measures to get that notion into the machinist's head. He pushed for a 4 for 7 firing order swap/Howard's roller cam and I really don't need that in a restored '65 GTO convertible. I talked him into using the Summit 2801 cam (also sold through Jegs, Crower, Sealed Power, Speed Pro, among others) which is like a 068 cam with more lift. Now we're on the same page and he has been working on my engine over the winter months.

So my engine will be relatively stock with a few upgrades. It will be a 5,000 to 5,500 RPM redline engine that will rarely even see 5,000 RPM. I am using the original 3.23 axle, and the car won't ever be on a race track.

I have used a stock replacement clutch for the 12-plus years I've had the car restored with the correct, non-numbers matching stock WT-code 389 without any issues.

My question is should I stick with a stock replacement clutch, or upgrade to something a little tougher? I checked out a Ram clutch (#88760) that is touted as a compromise between a stock clutch and a performance clutch. AMS has a similar one sold on Rock Auto.

I know I don't need a racing clutch, but I wonder if I should get a clutch that is a little stouter than a stock replacement.

As always, I appreciate and value your input.
 

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You might want to consider an aftermarket steel flywheel to replace the factory cast iron flywheel. You are most likely going to have to resurface your flywheel and with all those years on it, I would not be using it for safety sake. https://www.summitracing.com/search/part-type/flywheels/year/1965/make/pontiac/engine-size/6-4l-389/flywheel-material/billet-steel I have the Hays flywheel, but the Summit version was not available when I purchased my Hays some 10 years ago.

The aftermarket flywheels typically have 2 bolt patterns, one for the stock 10 1/2" diaphragm and disk and one for the larger 11" set-up. I would use the 11" set-up in a stock diaphragm style pressure plate. This will give you a little more clutch surface area to grab and the diaphragm will give you a stock pedal feel.

You will have to have your engine balanced and this will include the flywheel - which ever one you select. So keep that in mind.

Also, if you go aftermarket steel flywheel, the center section which bolts to the crankshaft is slightly thicker than stock - which is not a problem. Just make sure you get the correct bolts which have a slightly thinner head to match. Ask me how I know, LOL. In reading the specs on the Hays flywheel, it looks like they now include the correct bolts whereas they did not in the past. :thumbsup:
 

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Discussion Starter #4
Yeah PontiacJim, I am pretty sure my flywheel is the original and it was resurfaced at least once. I should at least have the machinist check it out or just look into a replacement.
 

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Discussion Starter #5 (Edited)
That Hays flywheel is quite a piece of merchandise. Is it more for racing purposes, or suitable for street use? Rock Auto has a 12 and 7/8-inch Luk brand flywheel for around $57. But maybe it's made somewhere that isn't found on a map. Otherwise, do I need to spend over $200 more for a flywheel and not realize $200 in gains?

http://www.rockauto.com/en/moreinfo.php?pk=4694979&cc=1350290&jsn=417
 

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My hydraulics gave out on mine and am surprised that there are so few posts on clutches. Only advice I see are for the LS7, Monster and cheap OE replacement Luks. There are a number of clutches on the Hawks Powersports website I cannot find any information on and they look like good quality.
Has anyone had experiences with Hayes, Ram, McLeod Hawks and/or Mantic clutches?
 

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I'm using a McLeod super street pro clutch kit #75217 in my 400. Pedal effort is not much more than stock and the Organic/Ceramic disc will grab like crazy when I want it to, while normal driving around town feel is good and not too harsh. Wish I would have done the steel flywheel at the same time though.
 
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