I recently just bought an 80-85 carbed 350 and am looking to getting up between 300-400 hp.

I don't want to replace the heads for money reasons.

I'm looking for the best setup to reach my goal, I already have a 3" flowmaster exhuast and edlebrock headers.

Everyone I've asked always tells me somthing differnt.

Can someone please help, give me some idea what it would take?

thank you

 

The heads are the single most important thing on a high horsepower engine. If you try to cheat there you might not ever reach your horsepower goals. Just my 2 cents.

 

Agreed on the heads but a little port/ valve work and you are there.
Or simply good fuel delivery and a cam combined with good exhaut 300HP+ no problem.

 

Since you want to go the cheap route you'll need a 150lb shot of NOS to help you get close to your 300hp range. Otherwise you'll need probably new heads, intake, carb etc. What type of rear do you have?

 

sorry buddy but the words cheap and horsepower dont go together. If they did wed all be driving around in 1000+ hp monsters.

 

first off, what heads are they?

what compression is the motor?

is the motor a roller block?



if the heads are ok, you may be able to do a lil port work, get the compression close with a thinner gasket, swap the springs on the heads, and put a decient roller cam in it and make your goal..

 

Cheap 300HP out of a 350 is very do-able.
I have a multiport 350 that hits 280HP with no mods all stock.
300HP is easy to get cheap. Whenyou start talking about over 1hp per cube youll have to start spending more money.

 

Gotta get heads, man. If you want cheap how bout a set of brand new vortec heads and some z28 valve springs for about 600 bucks. Thats not too much more than rebuilding and porting your old heads. Slap a comp extreme energy 274 cam and a good carb with about 10:1 compression and you've got over 400 horses.

Car Craft did an article on this engine a while back.

Have fun

 

I never said I was cheap, but everywhere I look heads are the most expensive.

I'v been porting them and makeing the ports as smooth as glass.

I planned on getting better roller rockers, to try and upgrade the heads without actually getting new ones.

I was also looking into replacing the stock intake manifold with a new one with matching cam kit.

Also what are the benefits to getting flat top pistons? Some one mentioned that to me but didn't explain why.

 

im sure you know, but incase you dont, and before SOMEONE i know on this board yells about it.... dont make your intake port perfectly smooth..... leave it at about a 80 grit rough...

 

Flat top pistons = higher compression

You don't need all that for your goals here though.
You can get over 300 HP with nothing but a cam some port work and upgraded intake and exhaust.
Yes heads will make a big difference but they'll also cost about doubble the cost of internals for a basic better than stock rebuild.
If you shop arround you should be able to get your internals (bearings$40,Gaskets$55,Rings$40, hot tank$70, cam and lifters$110) done for about $300 then you have intake and headers to consider. You'll still want to do all that stuff with or without heads but you might change your mind on what exact parts to get depending on the chosen heads. So if new heads are in your plans for the future you might want to keep that in mind when choosing cam grind, ring material, etc...

You can spend $99 on headers or you can spend $800 on em. You can buy new or used. It's really up to you. Cheaper usually means leaks(there are plenty of good leak fixes for cheap headers) and a short life. I personally wouldn't spend more than $150 on em unless I was going all the way up to stainless.

As far as an intake goes a stock aluminum flows plenty enough for 300hp or you could get a performer for under $100 I am sure.

Seriously any engine builder with some experience will tell you heads are the most important part of a high perfomance build. They will also tell you that 300HP out of a 350 is no challenge.
If you are more inclined to the 400 side of your chosen power range you'll be wanting new heads and more expensive/stronger internals. If your planning on 350 HP or less you should have no worries.

 

popping some 305 heads on it should increase your compression by about one point.

 

and they will also choke the heck out of his motor... lol.

 

Actually that is a common mod and on the 4" bore the 58cc heads can run 2.02 valves and flow quite well extremely hogged out.