Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: jcassity on October 21, 2014, 04:40:40 PM

Title: Flywheel help
Post by: jcassity on October 21, 2014, 04:40:40 PM
302 block being machined now
rotisserie will be a 331.
running an AOD on this build

machine shop called a few days ago asking I supply them with the harmonic and flywheel I plan to use so they can balance the bottom end.

I gave them the harmonic off a 1988 tbird and a flywheel off 5.0 explorer
they called today telling me I need to supply them with a 28oz flywheel.

what do I do?  I have a flywheel from a "D0" 302 block.

Are the Explorer 5.0's 50oz?

I thought I was good from the data in my diy link,,,,,,,,,,,,,,


Balance Factor Information
 --------------------------

 1981-and-up 5.0 HO - 50.0 oz-in
 1981-and-up 302 (non-5.0 HO) - 28.2 oz-in
 Pre-1981 289/302 - 28.2 oz-in
 351W and 351C-400 - 28.2 oz-in
Title: Flywheel help
Post by: jandmmustangs on October 21, 2014, 06:46:48 PM
Most 331 and 347 rotating assemblies use a 28oz balance flywheel/flexplate and harmonic balance. Long and short, find the correct plate/wheel and balancer to make it work. Remember, used balancers maybe have the outer ring spun. Me personally, I believe in using new parts for a new build. Especially a performance build. We can talk in depth about this over Halloween.
Title: Flywheel help
Post by: jandmmustangs on October 21, 2014, 06:51:16 PM
Also, all 81 and up 302 engines are 50oz. HO or not
Title: Flywheel help
Post by: jandmmustangs on October 21, 2014, 06:58:15 PM
Also again, all 351w engines used a 28oz balance and the damper does not interchange.
Just an FYI

Exploder 5.0 engines are 50oz balance
Title: Flywheel help
Post by: Aerocoupe on October 22, 2014, 12:06:13 AM
I'm pretty sure you can use one from say a 1987 F150 351W motor that you can buy at Autozone, Pep Boys or whatever car parts store you have.  The trick is making sure that the crank pulley will bolt up to the balancer and that the crank pulley will line up with the other accessory pulleys when you are done.  Just have them pull the correct balance for your accessory setup and then start pulling balancers and you should be able to find one.  I think all the early model 302's that were 28 oz are three bolt and the late model 50 oz stuff is four bolt with regards to the crank pulley bolting up.

While I do not recommend this I have read where people have done it and no issues.  I only run SFI balancers like Romac, FMS, or ATI but they are not cheap.

Darren
Title: Flywheel help
Post by: jcassity on October 22, 2014, 01:39:11 PM
well well..
interesting...
my harmonic needs to be 50oz yet the flywheel needs to be 28oz... that to start out.

sound odd to any of you stroker guys?

shop needs to take 28 grams off the crank.

Im just going to get new harmonic & flywheel from Liberty engine parts and be done with it.  not going to chance a used harmonic with a rubber that may or may not be perfect.

my spare flywheel is of an 88 Linc, so its a big weight , 50oz.  was considering getting a bone yard flywheel but for the price its moot since both will be under 170$.
Title: Flywheel help
Post by: jandmmustangs on October 22, 2014, 05:32:59 PM
I'll give you a ring here shortly. Lots to discuss
Title: Flywheel help
Post by: Haystack on October 22, 2014, 09:44:42 PM
Truck flywheels are all 164 tooth and have a different offset for the starter ring.

You just need a 28oz imballance flexplate.