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Discussion Starter #1
The heads that came on my 350 when I got it are as follows.
14102191- not great heads from what I could find. Well they have been worked.
1.94 intake
1.50 exhaust
3 angle valve job
Dual springs
1.52 roller tip rockers-comp cams
Screw in studs
Milled and now has 65cc chambers
Paired with and Edelbrock cam that I have pictured.

A couple of the intake valves tapped the Pistons.
My question is should I put some new valves in and use their heads, are they worth the cost of putting new valves in. And what is the potential with the cam.or should I change heads or cam or both. But first I would like to know the limits of this head/ cam combination, also I have a 600cfm carb and performer intake.
 

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using the same carb, intake, and 305 heads (14014416 casting #) cam is unknown, car has lots of punch we're having tuning probs. at the moment though. that's the way I got it haven't torn it down yet to look for 4 bolt or cam specs, still runs too good.
How much did the heads get milled for the 65cc chambers
 

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Be careful with the stock dual valve springs & coil bind at full lift. .540 lift is probably why your valves kissed the pistons. Just my own preference--i went with aftermarket aluminum heads,with springs that can take .600 lift. Can you do your own head work ? Those heads were 76cc before you milled them i think.
 

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Discussion Starter #5
I want aluminum heads but $100 for new intake valves is a lot cheaper than 900 for heads. No I can’t do my own machining this is just how I bought it. I’m pretty sure the springs are not stock
 

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305” heads are ran on “claimer class” circle track cars, they are a very inexpensive way to increase compression. That cam is too big for a driver car and your heads are very limited at higher RPM, the combination seems odd. You would be far ahead with a set of used Vortec heads and a much smaller hydraulic cam: this combo would make more power at ANY rpm level.
 

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Compression is over rated. To make power you need flow. Think of your engine as a big air pump. You cannot get more air in unless you can get the same amount out. I would much rather have a flat top piston with the right head over a point or two in compression with old, outdated, restrictive heads. If you just want to get it up and running I'm sure you can put valves in your heads. If you actually want to see the engine perform as it should put a set of heads on it. As already stated a good set of vortec heads can make very good power . If possible, put the best heads you can afford and match it with the right camshaft.

I'm running a similar sized hydraulic roller camshaft in my 65. It is in a ATK crate 385 engine with their 195 cc aluminum heads. It is fuel injected. I drive it any where I want to go, with cold air blowing and it gets 16 mpg but everything is matched. It has the right gear and converter and was built to drive. I do not even own a trailer. If it breaks I'm going to have to borrow one to go get it. So far it has 5500 miles and has been to cruising the coast three years running.
 

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You have a crate engine with matched components, that has sufficient valve to piston clearance. This situation is a little different, Alan has already bent some valves with his combination. And he seems to be looking for an affordable solution to this. Vortecs and a tiny hydraulic cam is an absolute foolproof setup that is very easy to install and maintain. Every car magazine around has written up dyno test on this same idea, it’s hardly original. A cam with about .440” lift, is easy on the valvetrain, makes excellent low end torque so your stock rear gears/ torque converter will be fine, and will idle with any carburetor you happen to have.
 

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"Compression is overrated" Seriously? It is an incredibly important piece of any good running NA package.
My advise: pack-in as much as you can while still using pump gas.
 

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Minimum compression is fine, Flattops with small chamber heads give you about 10:1. This is enough, and dome pistons are a bad idea on a pump gas motor. I truly don’t think any other mod on a budget motor gives the performance increase of Vortecs: the 64cc chambers are just about perfect on a 350 with flattop pistons, the modern heart-shape is extremely tolerant of low octane fuel.
 

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First question to the OP, what is the rear end gear ratio? And converter stall speed?
What is the intended use of the car? Cruiser? Just a little more power? Street/strip car?
With the performer intake and 600 cfm carb, that cam is pretty big, would need some gear and a stall converter to be happy, and a different intake manifold.
If it's just a fun cruiser, repair what you have, pull that camshaft out and go with something smaller, less lift and duration, .450 -.480 lift and like 206-210 duration at .050 with an rpm range of 1500-5500, sounds like what the rest of your parts are designed around.
 

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Obviously your heads have to flow but look at the old L76 365 HP 327. That little engine absolutely thumped. It wasn't so much the rumpty-rump 30-30 cam or the dbl hump heads, it was the 11:1 compression.
A monster in it's day
 

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Let me clarify the compression statement. Just as Midmo Joe said. A flat top piston with decent combustion chamber is plenty enough on a street engine. Anything around the 9.5:1 or 10:1 mark can build decent power. On a small block chevy it is all about the over all combination especially the head/camshaft combination. Once again, I think building a car is like putting a jig saw puzzle together. You put the parts in the right places and it will do what it is supposed to do once it is dialed in. Mix up a couple of pieces of the puzzle and it simply isn't going to do what is wanted. Any time you are messing with new camshaft, head or component changes piston to valve clearance should be checked. The components listed in the opening of this thread are mismatched. To get the most out of the engine some changes need to be made.
 
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