it was my understandling that NASCAR veto'd the new chevy motor...

 

They didn't like the ROX motor after about 6 revisions. It was previously the RO99, RO03 etc.... then Chevy said screw it and just made it available to the drag racers with a 4.500" bore spacing and a SB2 and Splayed Valve head.

Bret

 

whats the point of changing up the engines when nascar will just make them run restrictor plates anyway?!?!?

 

There are only a few tracks that require restrictor plates. The "super speedways" where they can reach 200+mph speeds.

And the point is to move away from the dated technology and embrace the changing market. If the motor was LS based they would definately "win on Sunday, sell on Monday"

 

i see what your saying, but if they wind up making another 100hp on average, some of the tracks that are currently not using restrictor plates will begin using them.
its cool that they are still running the v8's in that it makes better parts available to the public, but if they REALLY wanted to get back to the grassroots of nascar they would run the v6's that come in the cars from the factory. no restrictor plates and ease up on the rules, too!

anyways, i am seeing this aftermarket lsx block advertised right now and it is looking damn good!! if the cylinder heads available for it can step up its gonna be the way to go, imo. sb2.2 who? lol

 

With that 850 Main Body Carb, 358 cubes and 9500rpm limits they are not going to magically find another 100hp.

NASCAR's job is making the cars equal. GM wanted a new block to compete with the Toyota and Mopar Blocks. Right now Ford is still behind everyone else in terms of their blocks.

Bret

 

It's not power that makes them go that fast, because even with substantially less they reach that 200mph mark on the big tracks. It's simply how much time they have to get up to that speed before the corners.

And Bret is right, the new block isn't going to result in that much more horsepower.

 

A few more details were released on this engine the other day.

http://media.gm.com/servlet/GatewayS...75&docid=33365


"the R07's cylinder heads resemble production LS-series small-block cylinder heads with alternating intake and exhaust valves. While production small-block V-8 engines employ electronic fuel injection, the R07 port layout is optimized for the single four-barrel carburetor mandated by NASCAR."

"The R07's key technical advances over the SB2 include 4.500-inch cylinder bore centers (vs. 4.400 inches in SB2), a raised camshaft that improves valvetrain dynamics, a new six-bolt head bolt pattern that reduces cylinder bore distortion, and a targeted cooling system that minimizes temperatures at critical locations. A cast camshaft tunnel, integral piston squirter galleries, and overhead oil feed galleries reduce engine assembly time. Relocating the fuel pump to the inboard side of the car and eliminating external oil and coolant lines enhance safety."

I'm wondering if the LSX block was a huge hint at what this engine may be like? Does anybody have any idea if the deck height has been altered? I would assume that for these short stroke engines a short deck height would be used (if allowed by NASCAR rules...)

Who's gonna be the first to build an EFI street version of this?

And is it R o 7 or R 0 7?

 

R ZERO 7..... For the year 07

When I talked to a GM engineer he said that they had to limit the amount of castings each team was getting. I'm guessing it's going to be some time before the teams are running them in a race, as of December each team I think had enough castings for ten full motors, still a lot of time for R&D.

Bret

 

i'm very interested in hereing more about this

 

the newest issue of Circle Track (june 07) has an article with pictures of the new cylinder head. It's definitely worth picking up to read this article alone.

Does anybody have pictures of the block yet?

 

Saw one down in NC, they look a lot like the Mopar and Toyota stuff and not like a SBC.

Yeah take that Circle Track article with some salt.... the stuff on the head is good but MBE is another story. Not to say anything too bad but I know of some of his stuff works super as a door stop.

Bret

 

I know those guys.

 

:from USA Today