Discussion in 'The Garage' started by hammermachine, Jul 10, 2006.
Does anybody know about how much should a rebuild of a 305 cost?
more than its worth.
So it would be better to just replace it.
yes with a 350
If you get a 305 then I highly recomend getting an HO like one with an RPO like L69. Ones like that came out of 80s Monte Carlo SS, Camaros, and Firebirds.
The 305 HO I have is from an 83 Firebird and the RPO is LU5. Which means it originally had cross fire injection which sucked so now I have a carb on top of it.
My 305 HO has got some pretty good power. People don't give 305s a chance because they are labeled as the smog era's attempt at efficency.
305s can be made into screemers don't let anyone tell you otherwise.
having built quite a few performance engines, i have yet to see a "screamer" 305. i'll give it to you, a 305 is a good engine, but its no powerhouse. its main problems are the heads with smaller ports (which are barely enough to feed a 305), and the small bore which shrouds the valves. shrouding the valve only compounds the problem of too little flow in the heads. the 350's 4.00" bore breathes much better. the added flow, plus the added displacement will always equal more power. while most people think more power = more fuel, on mild engines the opposite is actually the case. an engine requiring less effort to move the vehicle is going to be more efficient. as you know, this is a truck site, and trucks are heavy. its very likely you will see a noticable difference in fuel economy as well as performance. take a 350, and you will absolutely blow the doors off of a similarly built 305.
305s make great car or light truck engines though.
Agreed, stock 305 heads suck. If you give them to machine shop they can port them to get a lot better flow out of them and fit bigger valves in them. This creates much more power than stock.
agreed, the ports can be helped a little. bigger valves however, will actually make them worse with the bore shrouding them. the only good reason i can see to run a 305 over a 350, is a CID displacement rule in a racing sanctioning body, or something where power and economy really doesnt matter that much (ie a demolition derby- what i use my 305 for). the advantages of the 350 are just too great.
The biggest valves you can put on a 305 is a 1.94 intake and 1.5 exhaust. Stock came with 1.84 intake and 1.5 exhaust.
some came with 1.94/1.50 from the factory, which is WAY too big for the bore.
Which 305s were they on? The 1.84 is stock even on the HO.
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