Roush VS. Ford Racing Engines

[Mr427]

FORGED!
Great discussion! Jack Roush has been one of the top FORD engine builders in America for over 30 years. Along with Wayne Gapp he ensured more FORD wins in Pro Stock (specifically categorized for Bill "Grumpy" Jenkins" and small block Chevrolets after 1971) than any single competitor at that time. After he quit racing himself, he became one of the architechts for a lot of high performance parts that Ford marketeted through its revived Muscle Parts Program. Yeah, I know, they called it SVO, the Motorsports, the SVT and now Ford Racing.

I have very little to add to the tech talk above, but I am appalled at Ford and Roush to even thinking about building ANY engine that they KNEW was going to be used for high performance applications WITHOUT forged pistons.

The term "hypereutectic" is a euphemism coined by TRW in the nineties. It means CAST CAST CAST. Nothing else. No engine, irrespective of size should have cast pistons if it is EVER supposed to see the south side of 5500 RPMS.

In its high performance supplementary publications, Ford talked about the "High Rev World of 5000 and Beyond". This sentence has meaning, because they all knew by then that an engine that passes this mark under stress is subjected to all new barriers of thermodynamics, fuel instability, ignition timing issues and a whole myriad of obstacles. It is like flying through the sound barrier. The RPM range from 5000 and up REQUIRES a different set of mechanicals, BEGINNING with forged pistons. The rest is a little more subjective, but there is one exception to all of this:

Ford´s early 429 engine is a case in study of how to do things right. Everything about this engine is amazingly correct. I am talking about the 1968 - 1971 N-code engine that was used to power hundreds of thousands of Ford vehicles. This engine has a nominal CR of 11,7 :1 and gets along with cast pistons. This engine in its stock form with headers and a 780CFM Holley would border on 400hp and run cars like the 1970 Torino and Cyclones into the mid 13-sec. time zone. It could take more ignition advance than ANY comparable engine of its time and it did all this, reaching high compression and power with flat top pistons.

Why am I going on about this? Because this engine is the exception to what I just said about forged pistons. :-)

[Don]

The specs for the 2006 Z06 Corvette 7.0 litre, 427 CI engine indicate the pistons are cast aluminum:

http://www.corvettemuseum.com/specs/2006/LS7.shtml

The 505 HP is at 6,200 RPM

[scottj]

Originally Posted by Don

The specs for the 2006 Z06 Corvette 7.0 litre, 427 CI engine indicate the pistons are cast aluminum:

http://www.corvettemuseum.com/specs/2006/LS7.shtml

The 505 HP is at 6,200 RPM

but... what does it tell you when Chevy builds 50 "performance" LS7s for a special project and the only difference between the production engine and the "performance" engine is that the performance engine has forged pistons.

[Anthony]

Originally Posted by Mr427

Ford´s early 429 engine is a case in study of how to do things right. =====. It could take more ignition advance than ANY comparable engine of its time and it did all this, reaching high compression and power with flat top pistons.

I generally thought that the more advance in timing an engine could take means the greater the combustion inefficiency, a bad thing.