10" vs. 10.5" Clutch

[Realmongo]

My '84 GT is ready for a new clutch. I was wondering if the switch to a 10.5" arrangement was a quick and easy bolt in replacement for the 10". If so, what parts will I need?

 

[Dean85GT]

check www.flemworld.com under rustang and how tos

 

[maverick0716]

All you need is a 10.5" flywheel from an 86+ 5.0L mustang.

 

[Realmongo]

Great! Thanks for the info. That site is pretty cool and loaded with great info!

 

[Daggar]

Hmmmm... the 10.5 will fit 86 and up 5 ohs, 96 to 01 4.6L GTs, 96 to 98 Cobra, and a couple of others. I believe that you have to stick with a 10 inch for 84 to 85. Not that the extra half inch will make any difference.

I'm just not sure what the driveline differences are between the 84,85 and the 86 up Fox bodies (other than the rear end).

 

[Daggar]

All you need is a 10.5" flywheel from an 86+ 5.0L mustang.

Whoops... there ya go! He tapped it out before I posted.

 

[SPEED FREAK]

the holes to mount the 10.5" clutch are on the early fly wheel they just need to be tapped and you can bolt the 10.5" clutch to the early flywheel. Make sure you resurface your flywheel tho.

 

[RsStanG1987]

the holes to mount the 10.5" clutch are on the early fly wheel they just need to be tapped and you can bolt the 10.5" clutch to the early flywheel. Make sure you resurface your flywheel tho.

I heard that but when i did my t-5 swap my clutch wouldnt work because the clutch disk would not work with the early flywheel. i had to buy an 86+ flywheel to use the 10.5

 

[SPEED FREAK]

I heard that but when i did my t-5 swap my clutch wouldnt work because the clutch disk would not work with the early flywheel. i had to buy an 86+ flywheel to use the 10.5

Really??? weird the 85 flywheel that I had kicking around actually had the same part number as my 91 flywheel but the pressure plate bolt holes were threaded in different holes. My machinist told me that's what he does with the early flywheels... Why wouldn't it work was your flywheel smaller? Or did the pressure plate not fit? I can't picture why it wouldn't work off the top of my head.

 

[Realmongo]

I think if I go the 10.5" route, I am going to just buy a new flywheel. Now the big question is should I go with:

aluminum

Or stick with the iron type?

 

[Daggar]

Unless you're planning a drag strip ONLY car, then stick with the steel. the lightweight flywheels cause drivability problems for street vehicles. Even the billet steel are not worth installing on a street car unless you're involved in a mototr sport where an SFI approved flywheel and scatter shield are needed.

 

[maverick0716]

I just bought a used flywheel for mine....just make sure it's straight and get it resurfaced.

 

[Realmongo]

How about the Ford # FMS-M-6375-B302 iron flywheel with the 50 oz weight?

Unless you're planning a drag strip ONLY car, then stick with the steel. the lightweight flywheels cause drivability problems for street vehicles. Even the billet steel are not worth installing on a street car unless you're involved in a mototr sport where an SFI approved flywheel and scatter shield are needed.

 

[Daggar]

How about the Ford # FMS-M-6375-B302 iron flywheel with the 50 oz weight?

Yep... you need a 50 oz imbalance 157 tooth. They're like $99 or something.

 

[Stang8URMPRT]

I did this upgrade on my 83. The 10 inch clutch BLEW, and no one makes a good upgrade for it. All you need is a 10.5 inch flywheel, which you can get one from Autozone or Advanced for 54 bucks if I remember correctly. it's a resurfaced unit. Good as new. You'll also want to get the dowels and metric fasteners from 5.0 Resto or what not. Then a good 10.5 clutch. It all bolts right up with no modifications. Just replacing the parts.