Quote:

---

I keep saying that using aluminum heads is NOT an advantage over iron heads on today's lower octane gas, whether they are BOTH 8:1, 10:1, or 12:1.

---

yes, you keep saying it, and I'll again say you're wrong.

We'll have to agree to disagree on this one

Quote:

---

I keep saying that using aluminum heads is NOT an advantage over iron heads on today's lower octane gas, whether they are BOTH 8:1, 10:1, or 12:1.

---

Go and try your hand at welding aluminum and then tell me that it doesn't have VERY different heat transfer qualities.

Detonation is caused by excessive heat in the combustion chamber. Because aluminum transfers heat away from the combustion chamber faster than cast iron, you are less likely to create the proper conditions to induce detonation.

Can you run a 10:1 motor with cast iron or aluminum, sure probably. Depends on lots of variables like cam, fuel octane and tuning. But all other things being equal, an iron headed motor is more likely to ping than an aluminum headed one.

Quote:

---

Quote:

---

some people should not post answers when they are wrong and or don't know!

---

Whether gas was better or not has nothing to do with what we are talking about.

The comment was made:

Quote:

---

10.1 comp might be to much with iron heads...

---

I said that iron heads were as high as 12:1 in the 60's.

W*T*F does that have to do with the quality of gasoline?

YOU don't know what you are talking about.

But don't take it from me. Here:
Iron vs aluminum heads

Quote:

---

guess what we learned? ...zero difference anywhere in the power or detonation characteristics of the iron versus aluminum heads

---

some people should not post at all when they are wrong and or don't know!

---

You are definitely challenged mentally and I guess we should recognize that and take higher ground.
BUT the limk you supplied is for a 10.88 to 1 CHEBBY RACE engine with race heads that have specially designed chamers and all. The cam is 260/260 duration @ .050 which on a little engine like that would be like a 272 @ .050 duraion cam in a 440 race race race you get it.

They set out to prove that the power loss myth that aluminum heads make less power than iron with everything being equal. the heads are the same race heads one aluminum and one cast with what will be a rich mixture (resist detonation as it slows burn) and they admit they never loaded it till high RPM's like having a 5000 stall and you are past detonation zone anyways

Plus their quote
"We're not going to be quite so cocky about debunking the claim that you can run higher compression on pump gas with aluminum than with iron. Our test does not definitively prove that. It may not have even tested it. We can say with complete confidence that we did not encounter detonation at any point during our testing, even at 10.88:1 compression. That could be because the cam was pretty big, with an intake-closing point 79 degrees ABDC. With cranking compression in the 185s, it was not taxing the detonation point even with 91 octane. Also, the Engine Masters thing has pretty well demonstrated that a dyno seems to have far more detonation tolerance than do actual driving conditions in a car. So, ultimately, we don't think we pushed that limit enough to make a positive finding."

You need to go back to real world school

Quote:

---

W*T*F does that have to do with the quality of gasoline?

---

Quote:

---

The original poster listed what he had to work with. On top of that he probably has tight budget. Why do members automatically start calling for aftermarket heads, forged pistons, roller cams ect. He has some template ported iron heads. If they are good to go and dont need $$$$$$ they are fine! (Great actually) I hope the original posters goal is realistic- what he is doing is like a stock muscle car kicked up slightly. Super drivable with no fussiness and runs 13s in the 1/4. An honest 375-400hp..ish?

---