Steve Bryant

iTrader: (1)

I've been very pleased that Toyota was joining the NASCAR fray for the 2007 season since I knew that their entry would turn up the heat on GM/Ford/Daimler Chrysler. Sure enough, GM is running a new engine series that is largely based on the Gen III/IV design from what I can determine http://media.gm.com/servlet/GatewayS...75&docid=33365. This development, the offering of the new LSX engine series, and the newly patented twin cam pushrod design with three valve heads and direct injection foretell the future. GM is advancing the breed.

What do you think?

Steve

Boosted LS1

Sounds very exciting. Any pictures of the engine schematics anywhere?

Mike.

Stang's Bane

iTrader: (22)

Speaking of Toyota, what engine is their powerplant based on??

Steve Bryant

iTrader: (1)

I've seen a TV documentary on the Discovery Channel chronicling the development of the Toyota engine. It is a NASCAR specific pushrod V8 with a layout pretty similar to what I suspect this new GM engine looks like (which I haven't seen at all). I'd like to see more, but I suspect that this GM NASCAR design is largely a derivative LSX concepts with a 4.5 inch bore center.

Steve

Stang's Bane

iTrader: (22)

I noticed the larger bore centers, sucks for us

CTSmechanic

iTrader: (2)

If you saw a Toyota engine on Tv it prob wasnt the new motor they run in Cup... but the truck series motor called a phase 9 ... When I was working for a Toyota Cup team the "New motor" was just getting put into vehicles to test while I was there...late summer early fall...

racer7088

The new GM engine is very similar to a Yates Ford engine with Dodge Bore Spacing now and the Ford sealed and Toyota super high cam tunnel. It's not too LSx derived really and has canted valves too like the Fords and Dodges and SB2 etc. It is now fully symmetrical like the Fords and the LSx though so no more hot spot anymore in the middle of the head like all the other GM stuff before it. It should rock.

A-man930

iTrader: (2)

You had me goin' for a second there! I've seen the scematics for that design, definately Intriguing...

gun5l1ng3r

I never understood what canted valve meant.
Could you explain a little bit?
My guess would be that the valves are more angled in the middle of the chamber(like a Hemi) vs being more flat like the LSx heads...

Torovair

The switch from Mirror ports to Symmetrical ports is interesting. When the SB2 first came out, I thought GM made a bunch of noise about how they R&D’d Symmetrical ports vs. Mirror ports and concluded that, in a single 4 barrel, carbureted application (NASCAR), the Mirror port arrangement was superior. They stated that the more even fuel distribution of the mirrored port intake manifold outweighed the hot spot issues of the mirrored exhaust ports.


GM appears to be retracting that statement with the R07.

-steve

BLKWS6

what kinda stroke would you use to get 358ci with that size bore????

NoRice

the phase 9 is basicly a dodge block, our mock up engines had dodge numbers on them the cup stuff is alongthe same lines.

Steve Bryant

iTrader: (1)

The more that I think about this, the program was on ESPN or ESPN2 and it was on Darrell Waltrip Racing and the affiliation with Toyota to help bring them into NASCAR. This program was not on the truck engine derivative, but was about the engine development (in California I believe), the car development, sponsorship, and all of the logistics that would go into making a viable team by Daytona.

Steve

purdueranger

iTrader: (11)

Vd = (# of cylinders )*(Pi/4)*(B^2)*S

S = 2.8137" with 358ci and 4.5" bore.

BLKWS6

yeah thats what i came up with...i was thinking it couldnt be right...that tiny of a stroke seems crazy...

carado1984

Did you ever see what those motors rev to when they do those in car shots of the speedo/rpms... ? Im guessing thats why the stroke is so small...

Steve Bryant

iTrader: (1)

Guys,
The bore centers on the new Chevy NASCAR engine have a bore center spacing (bore centers) of 4.5 inches (as opposed to 4.4 inches on other small blocks Gen 1 through Gen IV). If you know the bore (which I don't) then you could calculate the stroke of an engine. It's just the displacement (358 CID in this case) divided by 8 (the number of cylinders) to give you the displacement for one cylinder. Then multiply pi (about 3.1416) times the radius of the cylinder squared to find the area of one cylinder. Divide the displacement of the cylinder by the area of the cylinder and the result is the stroke. However, to do this, you need to know the bore regardless of the bore center spacing.

Steve

NoRice

most of the people shown on that show i worked with at TRD high point on the truck stuff. all the races engines are built in cali, shipped, then get redynoed in NC them handed to the teams by however, all i knew was i get the two of the better ones for the two trucks i put the engines in :o .

unless something has changed they run their cup program the same way the better running teams get the better stuff

racer7088

Yes the valves are canted into the middle of the cylinder instead of just opening toward the cylinder wall they now open more into the middle. This unshrouds the valve and port more as the valve opens. Most all of these race heads are canted valves in general. Basically instead of one simple angle the valve also lean inward as well and are also rotated around to make the intake port more line of sight and the exhaust like that as well also.

Stang's Bane

iTrader: (22)

Compare a BBC head to a sbc and it will give you the general idea..