Mustang Flywheel Guide | 1996-2023 Mod Motors

The main difference everybody talks about on mod motor flywheels is whether it's a six-bolt or an eight-bolt. That refers to the number of bolts it takes to retain the flywheel to the crankshaft.

To start off, the 1999 and 2000 Mustang GTs are a little confusing! Why? There was a fire at the Romeo engine plant, meaning they had to put Windsor motors from the F-150s into Mustangs. Most of your 1999, 2000 (and even some of the early 2001 models) will be Windsor-based and therefore have an eight-bolt crankshaft. However, some did slip through with a six-bolt crank. It is in your absolute best interest to check before you order a new flywheel.

When purchasing a new flywheel, there will be two main materials: billet steel and billet aluminum. A billet steel flywheel will be best suited for street use or in drag race applications that need that extra inertia to help you get off the line. A billet aluminum flywheel is best served in a road race-type application where you want instant acceleration out of the corners. Either way, you can't go wrong because mod motors respond well to both.

Unlike pushrod motors, you don't have various engine balances that you have to worry about. All of your mod motors, whether a 4.6, 5.4, or 5.0, will be a zero balance, meaning they're all internally balanced in the engine. On your pressure plate bolts, you have to ensure that you get the right ones because your 10-1/2 inch clutch uses a different set of pressure plate bolts than your 11-inch clutches. While I'm at it, just to throw another wrench in there, all your pressure plates will be 6 bolts up until 2011. In late 2011, Ford went to a nine-bolt pressure plate that carried through to 2014. And that's pretty much the long and short of flywheels for 1996 to 2023 V8 Mustangs!

Mustang Flywheel Applications

6 Bolt Flywheel

• 1996-1998 GTs
• Some 1999 & 2000 GTs
• 2001-2004 GTs
• 2005-2010 GTs

8 Bolt Flywheel

• 1996-1998 Cobras
• Some 1999, 2000, and early 2001 GTs
• 1999-2001 Cobras
• 2003-2004 Cobras
• 2003-2004 Mach 1s
• 2007-2014 GT500s
• 2011-2014 GTs
• 2015-2023 GT/GT350

People Also Ask

What Is The Function Of A Flywheel?

• The main function of a flywheel is to smooth the delivery of power from a motor to a machine by storing rotational or kinetic energy.

What Are The Signs Of A Bad Flywheel?

• Difficulty changing gears, a slipping and vibration in the clutch immediately after releasing the clutch pedal, or a burning smell.

How To Check Do I Check To See If My Flywheel Is Out Of Balance?

• Check for imbalance by revving to roughly 2500-3000 RPMs with the clutch pedal depressed and feeling flywheel vibration. If vibration increases with engine speed, then it is out of balance.