1966 mustang 289 flex plate????

I'm working on this 66 mustang for a guy and the starter is bad, I also noticed the flex plate is chewed up. I pulled the trans. Last night. I counted 160 teeth on the flex plate. I know the 157 is compatible. My question is do I get a 0 balanced flex plate? I also noticed someone has drilled it opposite the counter weight. There's about (6) 1/4" holes not all the way through. My other question is does anyone make a 160 tooth ring that can be put on?

Should be a 157

If the 289 has a stock rotating assembly, you'll need a weighted 157T flexplate. The drilling makes me think somebody has either rebalanced or TRIED to rebalance for some reason...maybe incorrect flexplate. Are you SURE about the 160T count?

Lots of little known details about '60's era small block balancing here: fordsmallblock.com/PDF/smallblockbalancing.pdf

I counted it twice, it's 160

That might explain the chewed teeth.

Same

I think I'm getting closer. I can use the 157 tooth, and it looks like I have to use the 28.2 oz. flex plate. I just have to make sure it wasn't rebuilt and internally balanced.

Check your harmonic balancer

My understanding on SBF only 157 or 164 every flywheel or flexplate I have ever had has been either or, 164 starter on 157 FP/FW = eaten and vise versa. Where or on what did the 160 come from...unique, crossed over, not sure. All the old SB's were 28.xx or 50 balance (newer) or 0

http://www.fordmuscleforums.com/c4-transmissions/502485-1964-260-v8-flexplate-160-tooth.html Old 260 V8 maybe?

Forgot about the 63-64 260 (early) C40Z-B /C40E-B is it a 10 3/4 bolt circle. could be a punched 260

I am thinking someone may have balanced it on a 289 because of the holes, but that is just a wild guess?

supervel45 wrote:I am thinking someone may have balanced it on a 289 because of the holes, but that is just a wild guess?

So the 260 wasn't 28oz balance?

http://www.ebay.com/itm/1963-Ford-Car-Flywheel-Ring-Gear-F-M-2-289-CID-160-Teeth-Galaxie-500-Custom-/221788897856?hash=item33a3a60240 This guy is claiming they came on 1963 289 2speed Galaxie's. It's an oddball deal, for sure.

Almost ALL 289 engines which came in factory vehicles were OEM 28.2 in/oz externally balanced. The ONLY one different was the 289 Hi-Po which had a small hatchet weight behind the damper pinned to the timing gear on the crank.

Flywheel/flexplate counter-weight never changed on the OEM 289 engines

Randy, what flex-plate was used on the Hi-Po engines?

crittersf1 wrote:Randy, what flex-plate was used on the Hi-Po engines?

A 28.2 in/oz 160 tooth flywheel/flexplate is used with some 5 bolt bellhousing engines. A 6 bolt bellhousing uses 157 tooth or 164 tooth, 28.2 in/oz or 50 in/oz flywheel/flexplate. (Except the Mustang II which used a 144 tooth 28.2 in/oz  flywheel/flexplate).
I think all Hi-Po's were 6 bolt bellhousing blocks with a standard shift trans; 157 tooth, 28.2 in/oz flywheel.

Thanks Randy. Just tore one down that looks like it was assembled by a 2 year old.