Thread: Got my hands on a 305 "h.o."

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Ok i got a hold of a good working 305 out of an 84 SS and i was gonna rebuild it. I was woundering would it would it be hard or should i say pricey to get it to see 240~250 hp rang? I am mabe gonna put it in my 86 cultass or mabe find me an cheap s-10, but likley im gonna put it in my cultass.

You might want to talk with Chevy37 who posts here. This thread may be of interest to you:

http://www.clubhotrod.com/forums/sho...threadid=18062

240 isn't hard at all to get out of a 305, good set of pistons and a good cam might do it, give the heads a good machine job...JMO

here i'll list what i did.....dont have the hp numbers yet, chassis dyno is after christmas.
1981 305 5.0 block
416 castings heads, 1.84" Int - 1.5" Exh.
1976 400 crank
stock 350 rods, they are a little beefier than 305's sam length
fully ported and polished, including chambers
1 5/8" hooker super comp headers
oldschool edelbrock torker single plane intake
600 holley, re jetted, smaller power valve
Custom Colt Cams camshaft 270 magnum:
221 @.050 on a 108 degree LSA
.465" lift with 1.5:1 comp cams roller tips
(1.6:1 will bring lift to .496") have not checked piston to valve clearances yet but if the 1.6:1 clear the piston, i'm going to run them)
Other items that will changed after the intitial dyno run are using a set of 1970 3973487 LT1 heads...1.94" Int.
I am expecting about 330 RWHP......Its pretty extreme for the 305 but I did this at a cost of $1600 Canadian.
All the head work was done by myself, that saved about 600 dollars.
So alltogether it was a pretty reasonable combo for the 305, even though it lacks the cubes it will be very reliable and street friendly to a degree. That camshaft in the smaller cubes will give it a very nasty idle quality so dear to our hearts. Hope this helps, this combo in my 1981 GMC Caballero should give a low 13's in the quarter, I do have plans to add a 100 shot of spray later next year.

If the motor is good the way it is, run it but search for a 350 that is good enough to run with just a clean up, cause that will get you at least 260 the way it is, and that will cost you less than a rebuild for the 305.

Looks like you've got yourself a winner. Should put out more than my 304 HP. Looks like were running about the same cam, but I'm running a smaller carb(600cfm), and with my pistons I'm running 9:2 compression. Nice job.