Within Stock rules???

[Ed Carpenter]

I was joking some people pm me need to lighten up!

[SSDiv6]

The cylinder heads are CNC ported as shipped by GM and they are part number 17802818.
They feature:
• 12 Degree Valve Angle
• 2.205" titanium intake valves
• 1.615" sodium-filled exhaust valves
• Max-Life Beehive-type valve springs
• Valve retainers and locks
• Intake and exhaust stem seals
• Intake lash cap
• 275cc Intake Port
• 90cc Exhaust

There is also another version of the 427 COPO engine used for Factory Stock that runs the LSX-DR cylinder head engine with larger valves and a 313 cc intake port and 110cc exhaust port. This cylinder heads run a CFE designed intake manifold with a Holey Dominator sized throttle body.

http://www.chevyhardcore.com/news/ne...take-approved/

There is another similar article on an LS3, 396 CID LS engine built by Patterson.

http://www.enginelabs.com/engine-tec...-stock-racing/

[Larry Hill]

More interesting reading on the ERL block that SAM uses.




http://www.enginelabs.com/engine-tec...-ls-lt-blocks/

[Tony Corley]

The Sam's guys are smart and know the rules. I would be willing to bet that they would pass teardown anywhere.

[Peter Ash]

Originally Posted by Tony Corley

The Sam's guys are smart and know the rules. I would be willing to bet that they would pass teardown anywhere.

Stock Cars Section 10A, page 3

CYLINDER HEADS

Porting, polishing, welding, epoxying and acid-porting prohibited.
Combustion-chamber modifications prohibited

External modifications prohibited.

and from the article "http://www.enginelabs.com/engine-tec...liminator-ls7/"

“The maximum intake port volume we’re allowed is 275cc, so we milled down the intake flange surface to shorten up the length of the port just slightly. This gives us some extra room to touch up the short-turn radius, bowl, and valve job area and increase the cross-section a bit without exceeding the cc limit,” Judson reveals.


hmmm?

[Tony Corley]

Originally Posted by Peter Ash

Stock Cars Section 10A, page 3

CYLINDER HEADS

Porting, polishing, welding, epoxying and acid-porting prohibited.
Combustion-chamber modifications prohibited

External modifications prohibited.

and from the article "http://www.enginelabs.com/engine-tec...liminator-ls7/"

“The maximum intake port volume we’re allowed is 275cc, so we milled down the intake flange surface to shorten up the length of the port just slightly. This gives us some extra room to touch up the short-turn radius, bowl, and valve job area and increase the cross-section a bit without exceeding the cc limit,” Judson reveals.


hmmm?

The heads come from the factory cnc ported. When you can start with a bare, unported version and run your own cnc program, you can make it virtually undetectable. If you read my statement, I said those guys are smart, and I would bet money it would pass teardown. And if it can pass teardown, then it must be legal, right?

[Peter Ash]

Originally Posted by Tony Corley

The heads come from the factory cnc ported. When you can start with a bare, unported version and run your own cnc program, you can make it virtually undetectable. If you read my statement, I said those guys are smart, and I would bet money it would pass teardown. And if it can pass teardown, then it must be legal, right?

After publishing their sneaky bits, they should get to experience an immediate and thorough looky loo!

[Dan Fahey]

These engines are 1970 Pro Stock Engines!

Originally Posted by Tony Corley

The heads come from the factory cnc ported. When you can start with a bare, unported version and run your own cnc program, you can make it virtually undetectable. If you read my statement, I said those guys are smart, and I would bet money it would pass teardown. And if it can pass teardown, then it must be legal, right?

what makes you think that the heads are not the best they can be right from GM? Why would you have to start with a new head anyway? These cars were build in a max effort capacity to begin with by a company that has every resource.

[Mike Keener]

There is nothing illegal about what ERL does to an otherwise stock GM block that bears the correct casting number. Here are the facts. The GM block as it comes from the factory is JUNK and is not usable beyond .005 over bore so there is no good reason for a serious racer trying to win in the Factory Shootout to leave the "maximum allowable" over bore rule on the table just because GM built a crappy block. If GM had built a "decent block" for these engines in the first place the work ERL does would not be necessary.

The only other legal option is to run a replacement LSX block that is easily over bored to the maximum allowable specification. However, there are not to many COPO's that can deal with the extra 100 or so pounds on the nose and still be able to race at the minimum weight for the Shootout.

Why do I know this stuff you might ask? The reason is because I did it and the LSX iron block over a sleeved block that is prepped correct!y is maybe 5 hp MAX which is not worth putting 100# on the nose of the car. However, the gain from an LSX block compared to a "stock" COPO block is worth at least 25 HP, but this is largely due to the gain from the extra cubic inches that can't be achieved with a stock GM aluminum block.

Bottom line is that it costs money to go fast, and going fast just isn't for everybody. Doesn't mean those of us that wish to compete at the very highest level shouldn't be able to do it with a clear conscience as long as there is nothing illegal in doing so.