Flex plate counter weight questions

Reply Subscribe

Thread Tools

Search this Thread

Jul 7, 2012 | 12:52 AM

DillonZ81ford

Thread Starter

Junior User

Joined: Feb 2010

Posts: 81

Likes: 0

From: Southeast Alaska

Flex plate counter weight questions

I am rebiulding a 300 six for my 1981 150 truck which has a 300 in it now with a C-6 Auto 2wd, The engine i i am building is out of an 1985 4wd with a 4 spd Manual. My question is this, Will my C-6 flex plate match up with my 85 engine and by match up, i mean is it balanced right for the 85 eingine? My dad rebuilt a 351 for his mustang and put a new flexplate on it. we had to pull it back out of his mustang to put the original flexplate back on because the new flex plate wasnt balanced right and caused the whole car to shudder slightly at idle, and i do not want this to happen to my Truck when i drop this engine in it.

so far my engine is coming together at full speed, i just dont want to have spent all this money to find out i have to track down the right flex plate, i should add i am building this engine at my home in southeast alaska, my truck is in the anchorage area in storage, almost 600 miles away, i am shooting for being able to swap enignes in one day, because i need my truck for college and work, so any delays to the swap would suck.

Thank you for any knowledge!

Jul 7, 2012 | 02:35 AM

68cabby

Laughing Gas

Joined: Aug 2011

Posts: 1,116

Likes: 0

Well..I use a manual tranny and a flywheel..but to my knowledge the 300 is an internal balanced engine..so the flexplate you get should have no counterweight on it..hopefully this helps your question.

Jul 7, 2012 | 03:14 AM

NumberDummy

Ford Parts Specialist

Joined: Nov 2006

Posts: 88,826

Likes: 785

From: Simi Valley, CA

D5TZ-6375-A .. C6/300 I-6 Flexplate.

Applications: 1975/96 Econoline / 1978/83 F100/350 / 1980/96 Bronco / 1984/96 F150/350.

It only takes 5 1/2 hours to fly from Anchorage to LAX. "She who must be obeyed" and I just returned from our 4th AK cruise (2004/2005/2006/2012).

Jul 7, 2012 | 01:58 PM

DillonZ81ford

Thread Starter

Junior User

Joined: Feb 2010

Posts: 81

Likes: 0

From: Southeast Alaska

[QUOTE=NumberDummy;12032328]D5TZ-6375-A .. C6/300 I-6 Flexplate.

Applications: 1975/96 Econoline / 1978/83 F100/350 / 1980/96 Bronco / 1984/96 F150/350.

My 1981 F150 Truck is all factory and has a C-6 bolted up to a 300 inline six

Jul 7, 2012 | 02:01 PM

DillonZ81ford

Thread Starter

Junior User

Joined: Feb 2010

Posts: 81

Likes: 0

From: Southeast Alaska

^ so is the I-6 the model of flex plate, and is f100/350 the F100 F150 F250 F350 ?

Jul 7, 2012 | 04:20 PM

Rogue_Wulff

Post Fiend

Joined: Dec 2007

Posts: 8,521

Likes: 16

From: Lost

When it comes to a 300, any year engine uses the same zero balanced flywheel/flexplate. Swapping a 96 300 into a 65, the original flywheel/flexplate would have the correct balance, so long as it was for a 300.
All 300's were internally balanced.

Jul 7, 2012 | 10:58 PM

DillonZ81ford

Thread Starter

Junior User

Joined: Feb 2010

Posts: 81

Likes: 0

From: Southeast Alaska

Thank you!

Thanks for the Info, this re assures my thinking!

10 Ugly Ford Trucks That We Still Kinda Love

Joe Kucinski

10 Things Every Truck Owner NEEDS (2026 Edition)

Michael S. Palmer

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Verdad Gallardo

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Joe Kucinski

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Brett Foote

Top 10 Ford Truck Tragedies

Joe Kucinski

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

Brett Foote

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Michael S. Palmer

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Verdad Gallardo

10 Best Ford Truck Engines We Miss the Most!

Joe Kucinski

Jul 8, 2012 | 02:08 PM

DillonZ81ford

Thread Starter

Junior User

Joined: Feb 2010

Posts: 81

Likes: 0

From: Southeast Alaska

Thank you!

thats all i needed to know

Jul 8, 2012 | 06:01 PM

#10

willowbilly3

Post Fiend

Joined: Jun 2003

Posts: 8,209

Likes: 12

From: Black Hills of SD

You have to be careful if you have a bunch of random Ford parts like I do. A small block flywheel will bolt to a 300-6. When I was piecing my 300 into my 92, I had a guy give me a "300" flywheel. It bolted on but turned out to be from a 302. I got the right one before it got installed though. Once when I was a kid I was mixing up FE parts and thought that big cluch and flywheel from my 428 would work good on a 390 I just planted in my 69 highboy.