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Author Topic:   305 vs. 350
Dirt Roller

Total posts: 24
posted February 06, 2003 05:44 PM
I need some help - I got a sbc with casting #355909. Mortec shows this motor to be a 305 Year: 76 - 79 2 bolt main. Can I make a 305 competitive with a 350ci in a Factorystock division on a 1/2 mile track? Compression is to be no higher than 9:1 according to track rules. The car is to weigh 3400# minimum. Would a Holley 4412 be better than a quadrajet for this motor as well in regards to volumetric efficiency? This is going to be my first year of racing but I do want to be highly competitive! This motor also has a TH350 behind it. Any help or information I can get would be greatly appreciated! Also what type of cam would be best for this motor? Thanks, Kent

Dirt Roller

Total posts: 15
posted February 06, 2003 05:56 PM
Last year I raced a Mustang with a 302 in it and was middle to end of the pack on a 3/8 mile. We took the car to a big race at a 1/2 mile track and looked like we should have been in the cruiser class. Most of the folks at that track were running 350's and 406's.

Just my experience.....Hope it helps.....Moved to a Camaro this year with a 350 in it.....Hope that this will be enough motor for the 1/2 mile.

Dirt Roller

Total posts: 24
posted February 06, 2003 06:05 PM
Thanks Dirtbandit! I guess I will keep looking for another motor!

Dirt Forum Champ
Total posts: 1565
posted February 07, 2003 12:16 AM UIN: 54865418
if you gear it right you might be able to keep up but not be very competative in that heavy of a car with a 2 brl get a 350 you'll be much happier i ran a stock 307 a few years back real good on super dry slick or sloppy but if the other guys could hook it up forget it bye bye birdy. if all else fails you can stroke it with a 400 crank we have guys around here that do that but it works best when it's not in traffic

Dirt Freak

Total posts: 346
posted February 07, 2003 10:43 AM
Chances are you are going to be racing against guys who are trying to cheat up a 350 to make more power than the other guy .... running 13% less cubic inches doesn't make sence (unless there is some significant weight incentive, but even then...).

don't give your competitors that much of an advantage.


Dirt Roller

Total posts: 17
posted February 08, 2003 09:12 PM
To put it in perspective, the bore of a 305 is 3.736, the bore of a 350 is 4.000, the stroke is the same so a 350 is like having a 305 bored out .264 (that's over a quarter of an inch) if you are locked into a compression rule, definetely the 350, it simply makes more power right out of the box.

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