351m to 400?

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Jul 21, 2002 | 08:38 PM

teamwizard

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From: Florida

351m to 400?

hey guys, i know u have to change the crank and pistons to change to a 400. do u have to do anything else with anything? is the flywheel the same, anything else i have to be aware of?
gabe

Jul 21, 2002 | 10:13 PM

GT40man

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From: Jax FL

351m to 400?

i think they use the same balancer as well. that should be it

Jul 24, 2002 | 12:58 AM

Big Blue4x4

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351m to 400?

>i think they use the same balancer as well. that should be
>it

Sorry, but the 351m and 400 use 2 totally different harmonic balancers as well as flywheel(manual) and flexplate(auto). Everything else is the same.

79 F150 4x4 410m Built Ford Tough!(9.1:1,KB pistons,custom Comp Cams X-Treme 210/218-.508/.524,roller rockers)/c6/3.5:1 gears,4.11:1 soon, Edelbrock 750, 285/75R16 BFG Mudders on alumn. mags with New Drk. Blue paint.
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Jul 24, 2002 | 07:30 AM

teamwizard

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From: Florida

351m to 400?

ok so i guess i cant use my 351m flywheel and balancer when i upgrade to a 400. Can u tell me what the difference is in the flywheel and balancer? are they a different size?
gabe

Jul 24, 2002 | 10:09 AM

beartracks

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From: Albuquerque

351m to 400?

I don't know the specifics but they are weighted differently to compensate for the larger throw crankshaft.

Jul 24, 2002 | 10:42 AM

Brian460

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From: Paola, KS

351m to 400?

If you have the engine apart already, then you can take the 400 crank and the 351m harmonic balancer and the flywheel to the machine shop and have it all balanced to work together. This would also be a good time to have the rods and pistons balanced.

Brian

Jul 24, 2002 | 07:32 PM

ecarter50

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351m to 400?

All you have to change is pistons/crankshaft. The flywheel/flexplate for 351M and 400 are the same. The 400 balancer is thicker but still balanced the same as 351m. I have done this conversion twice and there is no vibration problem.