tx_zstang

Nice, Ken04. Thanks for finding this.

Ken04

I had some experiience with the whole thing with some previous mod motors. Had piston slap in my 6.8 liter V10. The whole hypereutetic word seems like something cool, but it's actually just a word manufacturers use to make it sound like something really cutting edge, ha ha.

ABQstang89

Hey good find ken04. Always nice to have some clarification on what we actually have in our motors.

Wangstang

For what it's worth, I pointed out that Ford was using these in performance orriented production engines in 1993. Either way, Keith Black Piston company turns out performance orriented hyper pistons and these are used in many succesful all out racing applications. I know because I purchased a complete 302 bottom end from Jack Hidley of Maximum Motorsports...their in house engineer...from his race car when he was building a new motor. It used KB pistons. There are also plenty of examples of the 96-2001 Cobras and 2002-2004 Mach 1 32V 4.6L engines running around on road course and drag strips with blowers and no issues as long as Red Line issues are watched.

Livernois Motorsports did an indepth study probably 8 years ago on the factory 32 valve engines and piston failures. What they found by building a test stand and running the snot out of engines on a dyno was that excessive piston speed caused the failures. Essentially, when the pistons transition from moving up to TDC and quickly change their direction and start heading for BDC, the speed the pistons are required to move at higer RPM's is higher. The sudden transition resulted in the pistons failing in race applications due to excessive piston speed. When you reached a certian point in the RPM band, the piston pin would pull the piston pin supports/skirt off of the top of the pistons, tearing the piston in two.

Wes

ABQstang89

Piston pin failure is what I was talking about earlier in the thread when I mention the rods were the next to fail. piston pin...rod...guess I could have further clarified.

Wangstang

The piston failure in the boosted 32 valve engines has everything to do with engine speed and not power production which is a significant thing to keep in mind. If you can get a well designed blower kit on a 4.0L that could push a stock engine to 400hp before you get to 5K rpm, it should live a long healthy life. If we were talking about the traditional "cast" pistons, we would have a significantly different expectation for engine life. That's why the "Hypereutectic" term came along. It's more than marketing hype, it's a significantly different type of product than traditional cast pistons.

Hyper type pistons are probably the standard type piston in most production cars today beacuse they help control emmisions as they hold their size better as they heat up but in the Mustang world, Cast pistons were being used in engines through 93, perhaps a little later as well in the 94-05 3.8 V8's, but I'm guessing they also transitioned to hyper pistons as well.

Wes