what are the advantages/disadvantages of both. weight is the biggest factor I can think of. on ARIs website I saw that they have aluminum heads. did any GM car come with them stock?

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Josh

Under Construction

Sure lots came with aluminum heads stock.....Vega........chevette....LOL..just kidding! The 3400 pushrod had aluminum heads and quite a few others actually. Which engine specifically did you wanna know about?

Phil

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GTDude
OVER 25 years GM experience

Just don't even think about swapping aluminum heads over onto your 2.8 - there's been many a thread on that topic.

Aluminum heads are more prone to warping than cast iron. Cast iron can take more of a sh*t kicking. The most prominent difference is weight, and even that isn't much change.

My .02

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I WAS thinking about putting them on 3.1...I guess not from the response...are they more prone to warping on the 2.8 block? Why? aluminum heads are staple on most high. perf. V8s. right?

Does anyone know what kind of weight savings we might be talking about? I gonna go do a search. thanks for the input fellas.

If they have proper cooling, they are great. My old Cutlass has aluminum heads on the 2.8, the car ran cool and I never had a problem with them.

Our cars are more susceptible to overheating and running at higher temps. So if the car is driven hard or in contiguous races, the heads will be more likely to warp with aluminum than cast iron.

That's my understanding anyway. Please correct me if I'm wrong.

As for weight savings, I would have to look up the weight of each, because I'm not entirely sure. I don't think there is much difference between the weight of two.

from what i got in the archives...the aluminum heads have a different intake...I want to keep the stock fiero appearance...not to mention I don't want to have to worry about warped heads. you never know when a fiero might overheat.

The aluminum heads flow much much better than the iron ones..

But you need the 3100 or 3400 intake, and you can't install a distributor with those intakes, so you'd have to swap the computer over and go DIS, etc etc.

BTW, the main reason for blowing head gaskets on iron block/alloy head engine is revving the heck out of it while it's still cold. Doesn't last long when you do that. My quad is an iron block/alloy head, I've never had any problems, but I don't rev it above 3,000 until it's fully warmed up.

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1988 Quad 4 Coupe 5 speed
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The aluminum heads from a GM front wheel drive 3.1 will bolt up to the Fiero 2.8, but the aluminum heads use completely different intake and pistons (combustion chamber is shaped differently and you must use the correct pistons made for that head). Since the fuel injection is different, you'll need to swap over the computer, some of the sensors, and wiring from the donor car too. These aluminum heads do flow quite nicely. Aluminum heads require special head gaskets and they are slightly more prone to warping if you overheat 'em. Small block Chevy V8 aluminum heads are at least 40 pound lighter than the cast iron version. I don't know what the weight dif is on the V6 heads. Oh yeah, forgot about the different ignition system too (thanks Standard).

[This message has been edited by batboy (edited 07-06-2002).]

"All things being equal Iron heads will make more power but on a low HP/Weight aluminum heads may be faster because of the weight loss!"

That was from Pop mechanics a few weeks back.

I would love Aluminum heads on my car. Not for the power but handling.

Aluminum heads are used on modern high tech and high perf engines. Given an equal design, the aluminum will allow more advance, or compression (or both depending n application) because the aluminum will dissipate heat at a faster rate which will decrease the probability of detonation. But w/ regard to the 60 degree V6, the aluminum heads have a different valve configuration (splayed), which will flow better. Also they are obviously lighter. On the downside, if you car's cooling system is not up to par, you can damage them. Also if you lose a piston, rod or whatever, they are also more likely to be severely damaged.