anyone ever pep up a 305

[casey]

or is it a waste of time, I bought the old 305 that came out of my neigbors 84 chev p/u, It had 120,000 babied miles reg oil changes, couldn't resist for 100 bucks, I thought I might try and rebuild it myself, so look out boys the questions will come.

[69Elky]

i've got one in my 69 el camino moves quite good will beat the crap out of neighbors 71 ss350 elkyhis cars stock i've got 4.11's but who cares
mines got a stock bottom end polish and ported heads,edelbrock performer intake,650 edel carb, .480 lift ,hei dist,headers and dual 2 1/2 in exhaust with 2 chamber flows.moves alright


i bought 98% of my parts from powerhouse forget what the website was they sell a 335 stroker kit put a big cam and some heads on it and you'd be moving.

[Longhorn Man]

A couple years ago, car craft did a build up on the 305. They managed to get 325 horses on a dyno out of it.
They did all they typical bolt ons... intake, carb, HEI, double roller chain, headers, and a cam. This got them to a decent level, but then they got some Vortec heads and milled the crap out of them (to maintain compression...not to increase it) and the power increase was consideable.
I could try and locate the issues that ran the articles, but that may take a little time. (I've saved every mag I have bought since '90)

[mooneyes]

.......most people say its a waste of time..but i've got less thwn $400 in mine and it really surprised me how it runs...mine is out of a camaro with crossfire injection which came factory with flat top pistons..i tore it down put in new rings, bearings oil pump small summit cam and a offenhauser intake with a carter 600..and i've only ever had one mild built 350 that ran better...by the way if your going for a cheap rebuid i've had lots of luck with moly rings when not boring the block..they say they'll take up to .005 clearence..so if your bore isnt to lose its a cheap way out

[Smooth68]

bore it out to a 350 and change the heads and it will have some get up and go.

[67cst]

casey if you do i got an aluminum intake for ya, its an edelbrock preformer...

[Class of 69]

The compression ratio has alway's been the limiting factor on the 305, but you've seen some answers to that here. If your leaving the stock comp, use moderation. If you change pistons, then let it all hang out! Remember... a 69 Z28 only had 302 cubes, but lots of compression! Two fours, on a tunnel ram under a cowl induction hood would be awesome!!

[lukecp]

305's arent really a bad motor....but now one of the best GM produced. Every 305 powered truck i have drove (a '76 LWB and a '84 LWB), had good low end power, but when i put the pedal more than 1/2 way down, neither of them "go" anywhere near as good as my 350. I think this is because of the 305's tiny bore. They stroke is the same as a 350 (3.48"), but the bore is only 3.74" if i remember correctly. You could proably pick up a pair of Vortec 305 heads if you wanted, or maybe even a pair of heads off a TPI 305 (they are proably much better than stock truck heads). I have rode in a '97 Chevy with a Vortec 305, and it had no problem getting out of its own way. Acutally quite suprising for a 305.

[73stepside]

do not bore it to a 350. you can't. the bore is too small. they run really good. they are weak in the torque numbers but they will and have surprised alot of 350's. it is not a waste of time to work on a 305. just don't expect gobs of horsepower if you want it streetable.

[68C10]

Casey,
I am putting one from a '79 Caprice in my '68 because I got it for free. It's not that they aren't decent engines it's just that you get more bang for your buck with a 350. The parts cost the same but with the larger displacement of the 350 you get more torque and with our heavy trucks torque is what you need. Those of us who are old enough to remember the high winding 283s and 302s know that they came on strong at high RPM but didn't have much at low revs.
I'm doing a mild cam, Edelbrock Performer intake w/600 CFM carb and headers. It will give me decent running small block while I build a more stout 383.

[PanelDeland]

The biggest problem with the smaller smallblocks is what is called shrouding of the valves.This is because there is not enough area between the edge of the bore and the edge of the valve for good airflow.This means the engine gets less fuel/air mixture and less fuel/air means less power.Anything you can do to help airflow will help the 305.You will be limited on valve size especially with a higher lift cam.Make sure you have clearance between the piston and valves and between the cylinder wall and the valve(some 2.02 valves may hit the cyl.wall ;with some high lift cams I beleive the 1.94 valves may hit.).As stated before the smaller ones tend to run better in the midrange up so you could gear accordingly albeit at the expense of fuel economy.

[Longhorn Man]

I have always understood that you can not use 2.02 valves on a 305 becouse the bore is so small...is that correct or is it BS speculation?

[casey]

Originally posted by 67cst
casey if you do i got an aluminum intake for ya, its an edelbrock preformer...

depends on if I do it or not I know were I can get a intake Thanks 67cst and thanks for all the input everyone