redrilling flywheel

Reply Subscribe

Thread Tools

Search this Thread

Feb 16, 2008 | 04:18 PM

lasthighboy

Thread Starter

Elder User

Joined: Jan 2004

Posts: 668

Likes: 3

From: NW Kans

redrilling flywheel

im putting an internal balanced 460 in my 79 f-350. ive got a 12" clutch but the holes dont match up with any in my 390 flywheel. redrilling and tapping the flywheel is not a problem. i will space the holes out evenly away from the existing holes. just wanted to be sure it wouldnt throw the flywheel out of balance in any way. or if there was a certian way i needed to orient the clutch on the flywheel. if anyone can confirm this that would be great
thanks

Feb 16, 2008 | 06:14 PM

subs1000w

Senior User

Joined: Sep 2004

Posts: 218

Likes: 0

if it were me i would just get the right flywheel for like a 100$ but if you really want to i dont see a problem with drilling and taping the holes but personally i just wouldnt chance it id be hard to get it centered perfect

Feb 17, 2008 | 12:09 AM

cadunkle

Cargo Master

Joined: Oct 2005

Posts: 2,298

Likes: 27

From: NJ

If you can show me where to get a decent neutral balance flywheel for a 12" clutch on a 460... Well I'll be thrilled. I've got a 460 in my Galaxie and am converting from C6 to toplaoder. I need a flywheel but most places I look seem to be about triple the price you mentioned.

Feb 17, 2008 | 12:39 PM

subs1000w

Senior User

Joined: Sep 2004

Posts: 218

Likes: 0

well i figured it was a common flywheel

for a 79 f350 w/460 i checked advancedautos website and they show one for 50 plus core
autozone shows one for 73 plus core but neither say what size clutch they take youd probly have to call them but if a 12in was standerd for those thats proboly right but make sure you order throught the store so if its wrong its easy to retun it

Feb 19, 2008 | 06:40 PM

lasthighboy

Thread Starter

Elder User

Joined: Jan 2004

Posts: 668

Likes: 3

From: NW Kans

MOST people who do a 460 swap in these trucks use a 390 flywheel. earlier (pre 79)460's are internal or neutral balanced, as are 390's. apparently, most 390's use an 11 or 11.5" clutch, although 12" diaphram style is recommended for the swap. my truck already had a 460 in it with a 390 flywheel when i bought it, but i built a different motor for it and was replacing the clutch while i had it out. figured an upgrade for the same price was a good idea. (clutch from PIONEER, Luk pressure plate and Valeo disc i believe for like $275) 460's werent used with manual trans until 1983, and then were externally balanced. 429's were used with m/t in cars in the 60's, so one would think flywheels and clutches would be available. dont know why this is seldom discussed. i only recently became aware of this after i already had my parts.

Feb 20, 2008 | 08:09 AM

stuart1

Cargo Master

Joined: Jun 2003

Posts: 2,982

Likes: 7

From: Somewhere Saskatchewan

Just locate, drill & tap.

There is no need for any special orientation or drilling any extra holes.

The balance will remain the same because the bolts are equally spaced.

Feb 20, 2008 | 01:47 PM

lasthighboy

Thread Starter

Elder User

Joined: Jan 2004

Posts: 668

Likes: 3

From: NW Kans

was just going to set my pressure plate on the flywheel and measure 2 try to center as good as possible. there is no way to concentricate the pressure plate. i just took it to the machine shop and had them do it. only cost 30 bucks. not sure how they did it but said something about putting it on a lathe to center it up. sounds more accurate than my way. they make drive plates for irrigation motors so wasnt a big deal for them