Vintage Mustang Forums banner
  • Hey everyone! Enter your ride HERE to be a part MAY's Ride of the Month Challenge!

1 - 5 of 5 Posts
G

·
Discussion Starter · #1 ·
Car is a 68 with a 289 and a 4speed. I've got a flywheel with 164 teeth. At the time I got it I didn't know there was a 157 also. With there being two different ones and I not knowing which is on my car at the moment, are they interchangable? Friend of mine that works at Autozone says they are the same diameter, but the teeth are a little closer together so will wear out the starter. I'd like your advice on if I need to locate a 157 or I can use the one I have. Thanks for any insight you can give!

Andy
 

·
Registered
Joined
·
680 Posts
Crawl under the car, remove the bellhousing inspection plate. Mark one of the teeth with a marker. Remove the + battery cable. Now, have someone turn the motor over by placing a socket and ratchet on the lower pulley(crankshaft) bolt. You count the teeth....only way to know what you have is to count the teeth...
 

·
Registered
Joined
·
5,096 Posts
It is my understanding that 164 and 157 tooth flywheels are not the same diameter. I think the application for 164 tooth flywheels were for 351w's, but I could be wrong. The 164 will be too large to fit a bellhousing intended for a 157 tooth flywheel. Be advised of the two different imbalances for small block Fords. Pre '82 it was 28oz and 82 and up it was 50oz.

Unless you have something funky, you need a 157 tooth, 28oz imbalance flywheel.
 

·
Registered
Joined
·
2,750 Posts
164 and 157 are not the same diameter! The pitch of the teeth is the same however meaning that its 164/157 x 100 percent bigger (104.458%). You need a 164 bell housing and starter to accommodate one of these. It will mount 11" clutch components whereas 157 will only mount 10.5" clutches. The block plate is also different. I don't think this set up will fit early 289 blocks.

The starter partially interchanges because the pitch of the teeth is the same. Here's the gotcha. Since the diameter is different between the two flywheels, the only way you can interchange is if you use a Lakewood or other aftermarket bell housing that allows you to move the starter position. Why? The 164 has a greater diameter than the 157 and the bell housing accommodates most of the difference but not all. The 157 tooth starter has more teeth (10) whereas the 164 tooth starter has nine. If you try using the 10 tooth starter with the 164 flywheel, the teeth will jam and chip. If you use the 9 tooth starter with the 157 tooth flywheel, it will work but not mesh completely. The result is excess wear to your flywheel ring gear and the starter gear. Starters also vary according to nose depth. Always check the nose depth to make sure you have the right starter. Note: aftermarket flywheels may use the automatic starter (depends on the position of the ring gear) so its always smart to measure. Measure from the starter mounting surface to the inside edge of the nose piece. Compare this with the distance measured from the back of the ring gear to the starter mounting surface. These measurements should be equal. If they're not you have the wrong starter!
 

·
Registered
Joined
·
1,656 Posts
As others have stated, the 164 tooth flywheel requires the larger bellhousing. The 164 tooth flywheel was typically for the 351 engines, usually had a cast iron bellhousing, and is physically larger (dia). The 157 tooth flywheel, found on 289 type engines, typically came with an aluminum bellhousing and was smaller in dia. The block plates were matched to the larger or smaller bellhousings. One gotcha here is that many 289 engines came with 160 tooth flywheels which, in my experience, are interchangeable and compatible with the 157 tooth setups. I have an original 65 fastback's 289 flywheel (C30E-6380-B) and it has 160 teeth.
 
1 - 5 of 5 Posts
Top