Never heard of this????

[GTJAMMER]

Hey fellers,
I was looking at a 98' Cobra today. The fellow said that the engine was built by Dallas Mustang and they put undersize pistons in on purpose to make sound a certain way. I've never heard of this, how 'bout you. Is this for real or a bunch of b/s to pass off a blown engine. The car only had 34,000 miles, so I'd like to have it.

Thanks GTJAMMER

 

[bdcardinal]

ive never heard of using undersize pistons. i dont even think they make undersize pistons. undrsize pistons would create massive amounts of blow-by and would not allow enough compression.

 

[98SteedaStang]

Why would you want to change the pistons just to get different sound from a car? Mufflers would be a hell of a lot cheaper. Have you heard the car yourself? What does it sound like?

 

[jimfitzgerald]

That's total BS.

 

[70stangcoupe]

The only thing even relatively close I can think of is an old redneck saying "built loose for racing" meaning that the tolerances were wider so that you didn't have to wait for the motor to break in to run the piss out of it.

Undersized Pistons? They have NO IDEA what they're talking about. I'd call Dallas Mustang if I were you.

 

[n0v8or]

Perhaps they used pistons with a deeper recess or different height (length) to reduce the compression ratio, thereby permitting more boost without detonation.

The terms oversized and undersized usually refer to piston diameter. They may be using the wrong term, thus the confusion.

 

[geegee]

The DOHC 4v engine has wider tolerances owing to having forged pistons. We're talking about 0.002" or less overbore when compared to the SOHC 2v engine with hyperutectic pistons. The reason for this is forged pistons expand more under heat and need more space to grow.

The BS given you is just that,

 

[KaPPaBaLL]

if anything i'd talk to the previous owner to see what really got done to it.

 

[Blev]

Pull the VIN and call DM yourself. They may have the car somewhere in their system and could tell you exactly (if anything) was done to the car.