Got to looking on Weiands site and found this. http://www.holley.com/index.asp?division=Weiand .
Looks like some good numbers for for a l31 block and cam with the blower.

 

chevy hi performance built a 383 w/ vortecs, a good cam, and manifold and made 460 hp and 500 ft/lbs N/A. but it was a magazine article so...

 

I dont think I'd advertise only 462HP with a blower on a Vortec head motor... You can do that N/A with the right parts.

Friend of mine has a 3600lb Malibu with a 400, unported/stock valved Vortec heads, and a fairly mild solid cam and hes been 11.70 @ 113mph N/A... I'd say 460HP out of stock Vortec heads N/A is very doable

 

Well the 383 and 400 have more cubes than the 350 and Im taking it as its a stock L31 short block with a cam. You cant compare apples with oranges.

 

yeah the vortec version is just enough more expensive than the non-vortec version to make you just go buy nice aluminum heads instead of vortecs.

 

Yeah the vortec version is pricey but I already have vortec heads. The guy I work with talks imortall crap about the vortec heads but im staying with them.

 

how does he talk crap when you run 12.5 w/them, unless he runs 10's on stock l98's N/A

 

He was basing this off of his stock 327. Dome pistons, double hump heads with mild port work, and the .493 .512 solid cam for the 327. We have the same cars ,5 speed and 4.10 gears. His an 84 hard top mine an 85 t-top. I simply tell him. I have a smaller cam, stock heads, flat tops.. I just laugh because he actually drove my car and got the 12.56, lol

 

oh, so his motor is a lot more built up than yours. theres only one way to stop his trash talking then, isn't there.

that and it just shows the supremecy of the 327 over everything doesn' it.
j/k lol

what does he run?

 

He ran a 12.6 with the 327 revving the hell out of it. I was riding with him one time and he burried the stock camaro tach and it was still pulling!!

 

your faster, he shouldn't talk crap, YOU SHOULD.

 

The nice thing about a blower is that you can run it real mild and still make good power. My 142-blown 383 lays 390HP to the rear wheels (about 480 at the crank with a 20% drivetrain loss factor), which is OK, but nothing Earth-shattering. Certainly it could be made to put out that kind of power running N/A as well.

But it idles almost like stock, gets reasonable fuel economy, and works just great with a stock stall converter and highway rear gears. Compared to the alternative of a big cam, high stall converter and steep gears, I prefer the blower. Some people will not, however.