72-76 Cylinder Head Mods?

I honestly don't think I will ever "put" stage 1 valves in another set of heads,.. aluminum just makes more sense in every way. The larger valves themselves aren't worth the hassle.

 

Well i guess I have to start saving up! Maybe for the mean time if these stock heads are in good condition ill use them.

 

If they are later open chamber heads, don't expect much.

But please be aware, there are many a stout Buick big block roaming the streets with iron heads, so it's perfectly doable to have a good hard running engine with iron heads. But once you get hung up on a number north of 500 with street manners, aluminum heads make it much easier!

 

Lets say I rebuild the engine, bore it 30 over, get all good aftermarket parts, but i use stock heads, what hp should i expect?

 

I think that "all good aftermarket parts" leaves a lot of variables in terms of how much money you can spend. For my budget build I'm adjusting that to "only good aftermarket parts that I absolutely need to keep the engine from blowing up."

I just asked this question in my thread, but I think I may get some good answers here as well. If the OP is using stock style dished pistons, how much benefit will earlier, closed chamber irons heads have versus later 75-76 closed chamber heads? I was reading this:

http://www.automachperf.com/quench.html

And it got me wondering if the 1976 heads are actually the boat anchors people say they are for a stock type rebuild. To add some context, I'm considering spending money on earlier heads to replace my 76 heads and trying to figure out if it is worth it while reusing stock 1976 dished pistons.

Has anyone ever done a back to back comparison of late and early iron heads on a stockish 455?

 

Ive been looking at cams, can you recommend some? or just good companies?

 

a static compression test is just a regular compression test right? but how do I perform a compression test when the motor needs to built still?

 

I believe you are confusing two different things!

Static Compression Ratio (SCR) is the ratio between the swept volume of your cylinder(s) and the volume of your combustion chamber(s). Here is a good picture of SCR:



You can read about it here, along with DCR (Dynamic Compression Ratio):

http://cochise.uia.net/pkelley2/DynamicCR.html

DCR takes into account your cam choice but is based off of your SCR, hence why Larry doesn't want to recommend a cam until you know what your SCR will be. Most of the time SCR changes are made by changing the volume of the piston dish (or dome), the compression height of the piston (how far it sits in the bore), or the combustion chamber size (heads). Other possible ways are by changing the connecting rod length or stroke of the crankshaft (this is where "stokers" come from).

A Cylinder Compression Test is done on an assembled motor to help determine the sealing qualities of the engine's internals. I think you're getting it confused with SCR because they sound similar, but they are very different things. In this case SCR is used when planning an engine build and a Cylinder Compression Test is used on an already assembled motor.

 

Thank you that what was very informative! All understood now.

 

Have you been able to pull the casting numbers from your engine yet? That way you can know for sure what year components you're working with.

 

http://www.v8buick.com/index.php?threads/nos-1973-stage-1-heads-complete-ready-to-bolt-on.335311/

Wouldn't be a bad move should your heads turn out to be '76ers

 

Today im gonna start identify the block and heads. I dont think its a 76 but well see later.

 

Okay guys, I found some important casting numbers. So its a 74 block and heads.

 

What are your thoughts on hot tanking the block? Is it worth going to the machine shop or is it maybe something you can do at home?

 

I have all intention getting the cylinders bored and the decking the block after it's sonic checked. I was just asking about thoughts on hot tanking the block and heads at the machine shop vs at home.