I just picked up an engine today, needs a rebuild, but I'm wondering what I can expect out of it when its done, as far as HP and torque. looking for estimates of course.
I don't know much about it, except that according to the casting numbers its a 68-76 2bolt 350. it has a quadrajet on factory manifold, the heads that are on it are 70-80 1.94/1.50 76cc combustion chambers. I know that there are a lot of variables that can effect the results, compression ratio, cam, etc.
But if I keep it all stock with the block and heads that I have, what would be the minimum HP and torque I'd be looking at?

 

i'm not a speacilist on those years but im guessing 200hp/250tq if it came out of a truck, maybe 230hp if out of camaro. Am I close does anybody know? wait what am I talking about, 69 z28 with soild cam was rated at 360 hp. i have that cam in my drag car. If its that dont scrap it, keep the lifters together with each lobe when you disassemble it, and that year had "camel hump heads" check casting numbers as you can see it could be a wide range unless you know exactly what you have.

 

A '69 Z28 Camaro with a solid cam was a 302 rated at 290 HP. Not very likely that's what he has, as the country has been pretty well scoured for those gems.

You're looking at about 180 net flywheel HP, compared to an LG4 that had 145-165 HP. Since it needs a rebuild, keeping it stock doesn't make much sense. I understand budget limitations, but it's all about cost vs. benefits. A lame rebuild will cost at least half of what a good one will, so carefully consider how you're going to spend your money.

The heads and the intake manifold should be considered scrap metal. Stock LG4 parts are better than those pieces. I used to have LG4 heads. I still have a couple of stock manifolds; if you want a cheap replacement, let me know.

If you're willing to spend a little more, you can get Vortec heads, manifold, rockers, bolts, and gaskets, everything needed to install them on a 350 shortblock, from sdparts.com for about $1000. Money well spent, in my opinion.

Where you go from there really depends upon what choices you've made regarding the above. But, with a fairly inexpensive cam and those heads, you're looking at 300 HP easily.

 

thank you for the info. I REALLY appreciate it. 300 horses does sound nice :] I'd be happy with 250, but 300 would be nice too, LOL
We pulled the engine apart today, and I don't think I've ever seen an engine that clean before. NO sludge, harldly any carbon on the pistons or in the combustino chambers. the rod and main bearings were still all one color. there are visible marks in bottom of the lifters where the cam touches them, but you can't feel the mark yet, theres cross hatches in the bottom half of the cylinders. It looked like all the gaskets were new. All the oil and water passages were clean.
It must not have been together very long.... but long enough to blow two head gaskets and burn 4 intake valves, LOL

 

All the more reason to get rid of those heads. You might want to check the block deck flatness while it's apart.

 

that's exactly what I had in mind. I was originally planning on having the block tanked, honed, etc etc etc... but it looks like its been done recently. I may just be better off making sure the deck is flat and running a hone through the bores.
I still have to have everything measured for bearings and rings since I don't have any micrometers anymore.

 

for sake of arguement... lets say I use the stock heads, I won't because they are probably warped... but for sake of arguement, its a good baseline.
so what should I expect from that engine, with an eldbrock performer manifold, hedman headers, stock distributor, stock crank, pistons, rods, and an aftermarket cam big enough to add a little power, but not big enough to cause drivablity issues with the automatic. I need a converter anyway, but I don't want to go very high on the rpm on it, I was thinking 2000rpm stall for drivablity issues.
so, I have NO idea at this point what cam that would be but I'm sure you guys have some good ideas :]
so how much could I hope to add to that 180 with the headers, perormer intake, cam, no AC, no emissions, electric fans.

 

You don't have to worry about getting too big for the transmission, because the heads won't support very much.

With what you mentioned and an inexpensive Summit cam kit, you can expect somewhere in the 220-240 horse range. About what an L98 put out.

 

how much difference does boring make? I had the engine checked out today and they said the engine has been bored .60 over.

 

220-240 plus whatever I gain from the heads... I can live happily with that :]
I don't know what heads I'm going to wind up with yet, but I'll be sure to post when I do :] I've got a guy checking on a set of older heads that he THINKS had 202 valves.

 

1.94" Vortecs will outrun most older 2.02" valve heads.

 

I'd like to have Vortec heads... but, it looks like I am going to be picking up a cheap parts engine that already has an Edelbrock performer and I figure I might as well use that... so I don't have to buy a Vortec intake.

 

Proportional to whatever the displacement increase is.

For the sake of simplicity, assume 1 hp/cubic inch. A 350 would have 350 HP, a 355 would have 355 HP, and a 360 would have 360 HP.

So, if you have a 350 making 220 HP, a 360 making the same proportional HP/CID would have 226 HP. Assuming no limitations on the 220 HP - which probably isn't a good assumption.

 

so in other words, not enough to notice, LOL