FW10001 Buick 401 & 425 Nailhead Flywheel

This is a BRAND NEW steel Flywheel that fits Buick Nailhead 401 & 425 engines. The Flywheel is drilled to accept either a 10-1/2 inch or 11 inch GM clutch assembly.

This Flywheel is balanced for the 401 & 425 engines, so be sure you have a 401 or 425, as the 364 is a different balancing weight.

The 401 & 425 have the same balance. These Flywheels are machined in a way that you do not have to do any grinding on the crankshaft for them to work on all Nailhead engines from 1957 thru 1966. The Flywheels all have new ring-gears on them.

NOTE:
- If you are buying a Flywheel for a 1957 thru 1963 engine, you will have to use a starter from a 1964 thru 1966 Buick Nailhead engine.

- This Flywheel will NOT fit the 264 or 322 engines made from 1953 to 1956 in the cars. The 322 was also used in GMC trucks up until 1959.
It is important to check to make sure you ID which engine you have before ordering.

*Remember that the Buick Nailhead engines are externally balanced and you will have to take precaution to correctly orient the Flywheel to the crankshaft. Failure to do this will result in a severe vibration.

There is a sight hole machined in the Flywheel so you can see the alignment hole in the crankshaft while bolting the Flywheel on.


These Flywheels are machined right here in the U.S.A.!

We try to maintain stock levels of our Kit Components for fast delivery!

Please give us a call if you're not seeing what you need or if you have any questions!

*Matching our adapter kits with your engine can be tricky. If you are unsure of which kit to purchase for your engine, please call customer service at (763) 767-4480. Speed Gems is not responsible for return shipping costs of mismatched kits.

Speed Gems
806H S. Division St., Waunakee, WI 53597
PHONE: (763) 767-4480
EMAIL:  sales@transmissionadapters.com