tntz28

Do you think it is possible to get around 400 hp in a 1984 305 with a carb? and how quick will the get up and go be?

89RsPower!

anything is possible, the question is how much are you willing to pay? The cheapest route would involve a larger ci engine

tntz28

well i mean using that block, like with cams, intake etc do you think 400 hp is possible

five7kid

iTrader: (14)

There is a famous magazine article that took a carb'd 305, dyno'd it; changed cam, got more power; changed intake, got more power; changed heads, got more power; changed cam & intake again along with a bigger carb, got over 400 GFWHP.

What most people leave out when they mention that article is the engine puked a rod shortly after hitting the 400 GFWHP mark.

HP = torque x RPMs / 5252. The typical SBC makes about 1 ft-lb of torque per cubic inch, give or take a little (typically drops off as RPMs increase). That means an engine making 305 ft-lbs needs to turn about 6900 RPMs to make 400 HP. While 6900 RPMs isn't that big of a deal for a properly prep'd SBC, doing it repeatedly with a stock rotating assembly is a rod failure waiting to happen. But, properly prep'd means at a minimum high-end valve train parts, and is usually accompanied by forged (read: expensive) rotating assembly materials.

On the other hand, getting 400 HP out of a 350 shortblock under the rest of your '84 305 stuff would be much easier. Under the same assumptions, a 350 only needs to turn 6000 RPMs - much safer with factory rotating parts. Of course, if you're going this route, you'll likely do the right things to the 350 first, such as ARP rod bolts. And, you can choose to start with an '87-later 350 block which is roller-lifter ready, which makes it even easier to make good power.

And if you really meant 400 RWHP, forget it (unless you go power adder - in which case you're going to use forged rotating assy parts, high-end valve train parts...).

five7kid

iTrader: (14)

Oh, the "get up and go" part - it'll be a dog on the street. You'll need high ratio rear end gears, high stall torque converter if auto trans, and until you get some healthy RPMs up, it'll feel like the park brake is on.

1983cameroman

i remember it well i had 82 z28 t top car then i may still have mag put away at moms house

Street Lethal

iTrader: (16)

Here is a decent 305 buildup article for what it is....

http://www.popularhotrodding.com/eng...s/viewall.html

midias

As I recall the last 400hp carbed 305 I saw was very short lived.

But on the other hand a 350 with vortec heads can make 400hp very easy.

Jon87Z28

Thanks for putting up that article. You have given me inspiration and probably mapped out my "what's next" ideas.