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Author Topic:   305? or buy a 350? Street Stock Question?
posted November 10, 2003 10:24 AM
350 will murder a 305. Sell both running 305s to someone that needs one for their beater car, buy a core 350 and throw a rering kit, cam/lifters/timing chain and valve springs in it.

The only 'good' 305 heads came on 82-85ish HO 305's in Camaro's and Firdbirds. Casting number is 601. Any other 305 head will be a big cork on a 350 especially with the lift rule. I'd even take a set of 624 or 882 350 heads (late model, crack prone smog heads) over any 305 head except the 601. Yes, the CR will go up, but the valves and ports are to small.

posted November 10, 2003 02:23 PM
Weren't some old caprices outfitted with the 400? Why not go for the cubes with that heavy of a car and get a 400? Bore it 30 over and call one of the cam MFGR's for a recommendation to work with the lift rules that you've got....

Otherwise go for the 350, build as much compression as the rules allow - heck if you can run the later "factory" tubular corvette headers (from '87-up or so) I'd run those... Look for every HP advantage that you can in the engine (i.e. late model Caprice roller cam engine??)

Biggest thing to adress is a weight loss program and get the chassis set up to handle so whatever HP you produce will be put to the ground...

posted November 10, 2003 02:29 PM
I have raced against some 350's with my 305. I have a .410 lift cam, and a four barrel, and they are only allowed a 2 barrel, but alot more lift. (NOPA rules) But being I run the smaller cube motor, I am not required to meet minimum wieght of 3200. My car probably weighs 2800-2900. I kept up with them cars pretty good, but I wouldnt have if I had to weight 3200, and not have a 4 barrel.

So basically I am saying, ditch the 305's, and get a 350. if you build a 305 with the same stuff as the 350 on it (cam carb, and weight) the 305 will get killed. And dont use the 305 heads, they arent worth the extra copression, concidering small valves and ports.

posted November 10, 2003 04:53 PM
305 will keep up with a 350 a guy i race with runs right up front with us 350 guys

posted November 10, 2003 04:54 PM
find someone that has a big boat and sell them the anchors you've got. put together a 350 with some doublehumps

posted November 10, 2003 06:51 PM
i know from exsperiance the only time you want to run a 305 is if you plan on clai ing somebody that week i ran a 307 for 2 years and unless the tracks was super greasey or slick as ice i got stomped. and i'm gonna agree with everybody else the small valves will kill you on a small cam like that

posted November 10, 2003 07:23 PM
the 601 heads came on 305 4 barrel pickup motors also

posted November 11, 2003 05:56 PM
what would happen if you put big valves in the 305 heads?

posted November 11, 2003 10:45 PM
Junk the 305 heads and engines and get a 350 or 400 and have something that will run. There is no way to make a 305 that will run with a 350 running heads up.

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