jchittick

I have on 03GT with almost 64K miles on the engine. The girl who owned the car before me put almost 80 miles a day at least everyday when she owned it (all highway). I have the basic boltons, but near the end of summer and into next year, plan on modifying the engine on a higher level - cams, forging internals, etc. I was wondering how many miles do you have on your Mustangs when you decided to start building your engine.

LilGuysWearBowTies

Its not mileage, but money for me. If I had a 06 and the money, and I wanted a built motor, I would do it with 5 miles on it. Ive got 87K on my car, with a stock (internal) motor. No probs. I've heard of these motors going 150K plus with no problems.

04BlueGT

I had about 6K on when I started the bolt ons. When the warranty expires, then the fun begins. Either 3 years from now, or 39K more miles.

HaV

Im modding mine on stock internals at 125k on the clock..
If your asking because your worried about reliability with the amount of miles you have.. if you plan on swaping internals/seals/springs etc, its a moot point.

BCisme

i started at 100K. (right after i bought it) made 300 rwhp at 130K on stock motor. pulled the stocker out at 137K for the mach block, and now at 142K looks like my built motor is going in.