iron or aluminum heads
Thread Starter
Abby Normal
Joined: Dec 2001
Posts: 53,463
Likes: 92
From: Press "2" for English
iron or aluminum heads
hey guys. now that i have the '01, it's time to start considering options for the '81. i currently have a set of 2.02 open chamber iron heads (production). what i'm looking for is just a decent, reliable, SMOGABLE 300rwhp. since i already have the 2.02s would i be better off spending the ~$1000 on a set of aluminum heads or spend that same money on other parts to make the combination better?
what i'm planning (loosely) is for a CR around 9.0 to 9.5:1, cam in the 268-274* range, bowtie intake and headers with free flow cats.
obviously, i'm leaning to using the iron heads because i don't think my goals are really so high i would need aluminum to achieve them. granted, the aluminum might seem more glamorous but i think adding a 5th or 6th gear would be money better spent.
will the regular production 2.02s be able to support 300hp and still smog?
what i'm planning (loosely) is for a CR around 9.0 to 9.5:1, cam in the 268-274* range, bowtie intake and headers with free flow cats.
obviously, i'm leaning to using the iron heads because i don't think my goals are really so high i would need aluminum to achieve them. granted, the aluminum might seem more glamorous but i think adding a 5th or 6th gear would be money better spent.
will the regular production 2.02s be able to support 300hp and still smog?
Team Owner
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Re: iron or aluminum heads (clutchdust)
OH what a good question 
I don't know of a iron head that can't match a stock alum. GM head !!!!! if you can afford a switch to Alum. look
at it !!!!!!
[Modified by comp, 6:57 AM 6/24/2004]
I don't know of a iron head that can't match a stock alum. GM head !!!!! if you can afford a switch to Alum. look at it !!!!!!
[Modified by comp, 6:57 AM 6/24/2004]
Melting Slicks
Joined: Jun 2002
Posts: 2,844
Likes: 99
From: Orrtanna Pa.
Re: iron or aluminum heads (clutchdust)
My original plan was to stroke my 350 to a 383 and go for a streetable torque monster. The money spent on the stroker kit is fairly close to a set of aluminum heads. Well I got the stroker kit and landed a side job or two and ended up with aluminum heads too. In my opinion 400hp could be easily had with stock heads and some cubes.Running just heads would require a quite lumpy cam and cost you a ton of low end in the process.
Another concideration is heads can be changed with the engine in the car, the crank can not.
Another concideration is heads can be changed with the engine in the car, the crank can not.
Thread Starter
Abby Normal
Joined: Dec 2001
Posts: 53,463
Likes: 92
From: Press "2" for English
Re: iron or aluminum heads (The Money Pit)
Another concideration is heads can be changed with the engine in the car, the crank can not.
Melting Slicks
Joined: Dec 2000
Posts: 2,041
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From: Wichita, KS
Re: iron or aluminum heads (clutchdust)
Your cam selection will demand a few changes to the cylinder heads to work properly.
You need to pin the rocker studs or relace them with screw in studs due to the heavier spring pressures involved.
The passage where the pushrod goes through the head will have to be opened up a bit; or opened up a lot and guide plates installed to allow for the increased lift.
The valve spring seats will have to be enlarged to accept a larger spring unless your cam selection calls for a 1.25 inch diameter spring.
All of the above plus lapping in a new set of valves set me back 600.00 a few years ago. It sure makes a set of aluminum heads look more attractive.
You need to pin the rocker studs or relace them with screw in studs due to the heavier spring pressures involved.
The passage where the pushrod goes through the head will have to be opened up a bit; or opened up a lot and guide plates installed to allow for the increased lift.
The valve spring seats will have to be enlarged to accept a larger spring unless your cam selection calls for a 1.25 inch diameter spring.
All of the above plus lapping in a new set of valves set me back 600.00 a few years ago. It sure makes a set of aluminum heads look more attractive.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Re: iron or aluminum heads (1979toy)
It would be tough to make 300RWHP with stock heads. It is not impossible but you would need a perfectly matched up motor, 300RWHP is alot pf power it may not seem that much the way HP numbers are thrown around here.
To get 296RWHP from my L48 I needed SportsmanII heads, 10:1 CR a CC 282S solid cam, Victor Jr. intake and Holley 750DP.
To get 296RWHP from my L48 I needed SportsmanII heads, 10:1 CR a CC 282S solid cam, Victor Jr. intake and Holley 750DP.
