[66&04]

New to posting, but been reading on here for a while. Need help.....

I finished doing a C4 to T5 conversion on my 66 w/289 and have a problem.

There is a BAD vibration while in neutral & starts at around 1900 RPM & upward.

It does it either with the clutch pedal depressed or not.

Also really bad vibration driving down the road & again, pass the 1900 RPM.

I didn't have this vibration with the C4.

When I did the swap, I installed a pilot bushing (roller type), PP, flywheel, etc. All new parts & mounts.

Also had the drive shaft cut 3/4" & balanced.

My engine is a 289 & the new flywheel is supposed to be a 28 oz. that came in the kit.

I used the dowel pins for centering the pp & the disk alignment tool.

Torqued to specs.

I'm using a clutch cable setup.

Anyone have any ideas what the problem is?

I did notice the new flywheel had 2 allen screws holding the counter weight on, & is about 3" length & 1" in wide if that helps.

I'm wondering if I received a wrong flywheel?

If it is a 50 oz flywheel, how can I tell the difference between the two.

I mail ordered the complete clutch kit as a package.

The T5 I installed was used with unknown condition.

Could the older T5 cause this?

I've since bought a brand new Ford T5Z to use. But, I don't want to install this just to pull it back out if the vibration is still there.

[MustangOne]

Did you use the stock 157 tooth bell housing from the 66 289 or did you use the 164 tooth bell housing from a 1983 & up?

It sounds like to me that you use a the late model 164 tooth 50oz flywheel.

[66&04]

It is a 157 tooth bell and 157 tooth flywheel

[66&04]

Is it possible to get the flywheel balanced to confirmed that it is a 28 oz?

[MustangOne]

Can you see the the weight on the flywheel and compare it to the one on your flex plate?

The 50oz is noticeable longer.

[tireshredder]

dont you need 50 oz flywheel with the older 289, 302 and the 28 oz flywheel with the newer 5.0 (302)

[MustangOne]

1983 and After uses a 50 oz Flywheel

1982 and before uses a 28 oz Flywheel

[66&04]

I took both the auto flexplate, new flywheel & PP to get checked out.

Turns out that where the 3 alignment dowel pins go into the flywheel, the holes had not been machined deep enough to except the dowels,

Hence, the PP did not go flush against the flywheel.

Also, the balance was out 30 grams.....

I'm installing all this tomorrow (Saturday) & am hoping this has fixed the problem.

I'll let you all know.

[66&04]

Well, everything is in sinc now and works great. No more vibration.

A lesson learned. Always check to make sure those dowel pins go down all the way on after market flywheels....

[MustangOne]

Good to hear it is fixed.