or 11."
Clutch question...
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From: chepachet ri
Clutch question...
1981 f-100 vin# says it came with I-6. Currently sporting 302 small block with NP-435. I find two clutch diameters , 10.5 or 11". My question is on whether or not the flywheels on these trucks are drilled to accept both sizes. Thanks for any info.
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From: Denver Metro Area, CO
Yes, look at your flywheel before purchasing parts; at some point, Ford started using replacement parts that were drilled for both but I believe this didn't happen until the mid-80s sometime. Best thing to do is look at what you have....
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Joined: Mar 2013
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From: Arkansas
I don't have a pic, but just got done rebuilding my motor and installing new clutch, i have the smaller one, but mine had 2 sets of holes, and i am assuming the holes on the outer band would be the holes tapped for the larger clutch. Mine is an 85 BTW.
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Ford Parts Specialist
Joined: Nov 2006
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From: Simi Valley, CA
Since, as you say the engine has been swapped, you cannot go by autoparts store clutch applications for an '81 F100 302.
It's also impossible to answer the flywheel question, as it all depends on what the 302 was originally installed in.
If 302 came from: 1981/83 F100, 1981/87 F150, only one flywheel is listed. But, if it's from anything else, including 1969/96 trucks and 1968/96 passenger cars...the possibilities are endless.
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From: Rexburg
I ran into this while I was building my straight 6. I put in a new clutch and flywheel while I had the engine out. Parts guy asked me which one I wanted. My friendly tranny shop filled in the blanks. You're truck can use either clutch. IF... the flywheel is drilled for both sized. Just be aware that if you change the size of your clutch you are going to have to round up different sized bolts. Don't know why but each flexplate has it's own bolts.
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