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Author Topic:   305 or 307?
8 fan
Member
posted September 27, 2004 05:47 PM
I am going to run a pure stock class next year and was wondering what engine would be better, olds. 307 or chevy 305? cannot modify engine in any way no audible cams, stock heads must be used, can use 2 or 4bbl. carb. stock manifolds.I will be running a 1983 olds. cutlas body.will be 1/3 mile dirt, any suggestions?


racer17j
Member
posted September 27, 2004 06:07 PM
i would go with the 305 or a 307 chevy if you can find one but not the olds. to heavy and if you planned on doing an over haul would cost you more too


51racing
Member
posted September 28, 2004 07:57 AM
quote:
Originally posted by 51racing:

What track is this for?
The rules sound to me like my usual track, Kopellah's in St. Croix falls.

it is monster hall near unity wi.

51racing
Member
posted September 28, 2004 02:55 PM
quote:
Originally posted by 51racing:
Oh, sounds like the rules are pretty similar. We are simply limited to a 320 inch motor, cast intake and 2 or 4 barrel that matches manufacturer (gm-quadrajet etc.).
I run a 307 in mine, I think it's a much better motor, has the same stroke as a 327, uses the smaller balancer etc. The factory heads are where it is lacking. Do you have a head rule, or can you go with something other than the heads for that motor?


we are limited to either a 305 chevy or 307 olds for gm vehicles, must use stock heads for either motor with a limit of 1.84 for intake valves 1.50 exaust


jakedawg23
Member
posted September 28, 2004 09:16 PM
late model 305. Olds 307 have small intake and haed ports,I had trouble geting over 5000 rpms.


BrianW
Member
posted October 01, 2004 11:26 AM
Vortec headed '97-up 305's will be the best power - add a true flat-top piston and mill the heads a bit to gain some compression and it'll be a great combo. You'll have to run the GMPP or Marine carbed intake manifold and then Go with a "vacuum rule" cam and you should be able to make as much power as the rules allow and still remain "legal"