heavy duty 250 clutch

[shelby987]

I will be upgrading my tired 250 for a recently built 250, and to save time I think a clutch replacement is in order when the engine is going in. The truck was originally optioned with a heavy duty clutch....would buying another oem heavy duty clutch be my best bet for a higher hp/tq application? Spent a decent amount already, so I am not looking for anything super high performance, just something that can withstand that hp/tq when it is used.

I see specs for 10", 11", 10 spline etc, but it all references sbc...my 250 should use the same clutch right?.....can anyone lend advice? The truck is a 3spd on the column....pretty sure its a saginaw, can anyone give advice on this....its a 4x4 too if that helps.

Also, what do I do about a flywheel....I know there is internally and externally balanced, what is the difference (one is balanced to the engine, and the other is balanced alone correct?) Can I use my original flywheel or should I buy another one (I know it needs to be turned first, can it be balanced?)

[70rs/ss]

Originally Posted by shelby987

I will be upgrading my tired 250 for a recently built 250, and to save time I think a clutch replacement is in order when the engine is going in. The truck was originally optioned with a heavy duty clutch....would buying another oem heavy duty clutch be my best bet for a higher hp/tq application? Spent a decent amount already, so I am not looking for anything super high performance, just something that can withstand that hp/tq when it is used.

I see specs for 10", 11", 10 spline etc, but it all references sbc...my 250 should use the same clutch right?.....can anyone lend advice? The truck is a 3spd on the column....pretty sure its a saginaw, can anyone give advice on this....its a 4x4 too if that helps.

Also, what do I do about a flywheel....I know there is internally and externally balanced, what is the difference (one is balanced to the engine, and the other is balanced alone correct?) Can I use my original flywheel or should I buy another one (I know it needs to be turned first, can it be balanced?)

The clutches are sold by diameter, I put the flywheel from a 68 on my 90 truck, so they fit any. I'd suggest a good quality clutch (RAM, centerforce, Hayes) Summit sells em as cheap as I have seen and the Ram is like $160 ish for clutch, pressure plate, throwout bearing and alignment tool. It should hold up to any 250. As for balance, I think the 250 is the same as SBC except for the 400 which is external balance.

[truckdude239]

i put an dinopak clutch from o'reilly auto parts cost me 100 buxs ( clutch disc pressure plate polit bushing and throw out bearing

[lilred67]

i installed an 11" clutch in mine from NAPA. i think it was just over $100.00.my truck was oringinally a 3 speed but it now has a sm465 4 speed.i used the same clutch with both tranny's.

[passthebuck]

I did the clutch in my 3sp/250 last summer & i put in a 12"er. They say do all three-new clutch plate, new throwout bearing & new pressure plate. I'd be inclined to agree- all new stuff & you wont be back there again anytime soon. I had my flywheel reground too. I upgraded to a 12" clutch while I was there. I got a kit-clutch plate/throughout & pressureplate. I didnt NEED a 12"er but it was a $15 upgrade from an 11"er & one day I'll put more power infront of it. It was an OEM clutch that they use behind GM diesels I'm told so it should take a tonne of power. If you had a 10"er, then you have to put a 10 back in, but if you had an 11" you can put a 11" or a 12" in. I walked into a local clutch shop with the flywheel, clutch, pressureplate & throwoutbearing & asked for a new setup. they ground the fw & got me a clutch kit for diesels that have the same transmission spline count as our transmissions. they'll be able to regrind your fw if it hasnt been ground too many times before. Any Questions?

[Green Machine]

All the trucks I've seen had the 11" clutch, I thought the 10" clutches were used mostly on small block cars ? Anyway a stock 11" will hold any 6 banger and most small blocks, a heavier duty 11" will hold most built small blocks and mild big blocks. I've heard not to use the 12" clutch as the extra mass of the larger disk makes the trans synchos work harder and can slow shifting if you really want to shift fast, if you really need more than an 11' to hold it you should look at a dual disk setup - my 2 cents.

[passthebuck]

i had heard that too Green Machine & ya, i did consider it bigtime. I wasnt sure what to do. In the end, I knew I would wear out the clutch before I was gonna change the SLOW 3-on-the-tree column. & after installation, I cant say as I notice much of a difference. I bought a towbar to tow my green 67 with my red 67 to get saftied & I'm glad i had the big clutch cause I sure had to walk it out of the hole with the wee L6 pulling all that weight.