So i recently pulled my 351m to install a 460. I have my original 351m flywheel and clutch kit and a 351m bellhousing. transmission is still in the truck. Can i use the 351m flywheel and clutch? ive heard need a 390 flywheel but nobody can say why.

 

390 wouldn't make sense to me...that's a completely different engine series (FE)...but stranger things have been true I guess.

I'm going to try and get someone who has some experience in this very issue to chime in. It seems to me, if I remember correctly, that there is an issue with how far the pilot bearing sits in the crank on the 351/400M vs the 460.

 

I've also been looking for a flywheel for a 79 460.


Looked at listings on summit, and, they list a 390, 429, and 460 under some of them...

 

I just did some more searching, you can use. Flywheel for a 79 and newer 460 for a 79. 78 and older can use the 390 flywheel

 

I guess I'm a little confused with the original question.

You're swapping the 351M for a 460 and wondering if you can use the 351M flywheel and clutch, legitimate question.

You also state that you were told you "need" a 390 flywheel. I was unaware the where compatible but if you're going to go get a new flywheel, why not get one for a 460?

The way I see it, you have 3 optoins:

1) use existing 351M flywheel, if it's compatible
2) get one for a 429/460
3) get one for a 390 (but why would you do that?)

 

i have a 78 460 that had a 390 flywheel. its ok if you only plan to pull start your truck every time you wanna drive it which i highly doubt. ive put a new flywheel on once and have been through two brand new starters. it eats the teeth off every time. dont use a 390 flywheel they wont match up. you cant put a 390 starter on it.

 

I know for a fact you cannot use a 80s or 90 stock 460 flywheel with the 351M/400 bellhousing. I tried to do it and the flywheel is too thick and the geometry of the throwout arm is off and it binds up. Best advise is bite the bullet and pay the $600 for the L&L flywheel and clutch set. Use a pilot bearing for a 302 motor(it installs in the smaller of the 2 holes in the back of crank). This combo works. The 390 flywheel, I don't know about. I have heard this as well, but haven't tried it.