You can type here any text you want

Aluminum vs Irons

Welcome!

By registering with us, you'll be able to discuss, share and private message with other members of our community.

SignUp Now!

J-B Racing

Forced Induction
Joined
Sep 16, 2003
Messages
2,466
Hey guys..
I have been researching on this issue for a few years now. This is for the reason that I have been running Iron Heads for over 10 years now. I have ben told by some Aluminum Head users that on a 109 ( 231 + ) Block, the Iron 8445 Race Ported have made more HP and better ET by .2 to .3 on the 1/4 mile. A few people that I know took off their $$$ Aluminum`s to go back to Iron and picked up what they lost.. WTF is up with that!!!
Since I had to take appart my 109, I have been thinking of going with AL Heads, but I am still undecided.
Maybe the TSM Heavy Hitters can elaborate here and tell a story?

For me this is good business since I have been Porting the Buick Irons for 10 years...

Thanks
Joe
 
Hey guys..
I have ben told by some Aluminum Head users that on a 109 ( 231 + ) Block, the Iron 8445 Race Ported have made more HP and better ET by .2 to .3 on the 1/4 mile. A few people that I know took off their $$$ Aluminum`s to go back to Iron and picked up what they lost.. WTF is up with that!!!


I would think the majority of the TSM guys will tell you they have had opposite results.
 
I would think the majority of the TSM guys will tell you they have had opposite results.

That's what I would think too. But this is not the first time I hear about this.
One person told me that it has to do with the Temp in the Runners...:rolleyes:

This is getting confusing.
 
Hey guys..
..w. I have ben told by some Aluminum Head users that on a 109 ( 231 + ) Block, the Iron 8445 Race Ported have made more HP and better ET by .2 to .3 on the 1/4 mile. A few people that I know took off their $$$ Aluminum`s to go back to Iron and picked up what they lost.. WTF is up with that!!!
..........Thanks Joe

Sounds like you need to hang around with different people?:confused: They are doing something wrong?

The simple fact is that alum heads have bigger [larger diameter] valves, hence they flow more air. Since horsepower is made by getting more air and fuel in the combustion chamber, common sense then tells you more air flows through the alum heads.:smile:

Iron head valve size is limited by spacing between the intake and exhaust valve, so larger valves are not an option with them.
 
I read in Car Craft, I believe, that all other things equal, Iron heads will make more power; however, as mentioned above, things are not equal between the AL and Iron heads for our cars.
 
Funny

I guess you guys can laugh it out for a while. I got my answer from some very knowledgeable people on this Board explaining to me why their is a Loss of HP with Aluminum Heads.
I will leave it up to the Comedians to figure it out.:D

I want to thank those who took the time to answer my question..:)



Joe
 
A little "birdy" who has been around buick racing for a long time, had this same discussion with me. You can run more boost to make up for the lack of valve size in the iron head vs. the alumimum head. Iron heads tend to hold a gasket better.(more weight, etc..) The same birdy told me they made the same power on a test car with alum. heads @ about 4-5 psi less then irons. I will be testing the outer limits of some Iron heads soon...will report back. :D
 
I sure would like to hear that explanation of why FACTORY 8445 irons are better. If you are talking TSM type cars and looking to go FAST. Irons do have some great benefits but they have limits...

10 sec cars are fine with irons, awesome for a street cars. You show me one Iron headed 109 that ran 9.30 or less with a 70mm turbo.

There is one other explanation, maybe the guy was talking stage II heads... Anderson Performance is putting them on a 109 for us. Mike at Full Throttle's project I picked up and we are going to finish. That will be interesting:biggrin:

Not knocking anyones train of thought, just would like to hear a good explanation:smile:
 
I've heard this before as well however I believe it applies when you have two identical heads made out of the different materials with identical ports, valves, etc.... With TR's, ported irons and aluminum heads are quite different so you're comparing apples and oranges.
 
I've heard this before as well however I believe it applies when you have two identical heads made out of the different materials with identical ports, valves, etc.... With TR's, ported irons and aluminum heads are quite different so you're comparing apples and oranges.

Very well said!
 
I spoke with Tom at Champion at great length about this.
The irons are good to the tens ALum is the choice for faster.
Irons are alot more forgiving to detonating the alum.
I asked on a rebuild would the alum make power better/easier than the irons?
His recommendation was get the irons and sink the savings over alum in a roller cam.
Pretty straight forward.
 
Findings

I would like to start by saying that I NEVER said that the Iron Heads would be the Best Choice for going the FASTEST.
I want to give a ET Range from let say 9.70 to 10.40.
I was told that anyone running in these Times with Iron Heads and switching to Aluminums, the car would slow down.
WHY...
In this case the Answer is because of the HEAT Transfer in the Runners.
The Aluminums would retain more Heat and cause some HP loss.
CORRECTION
Someone told me to use some kind of Heat Barrier Coating in the Runners and the Combustion Chambers to adjust HP correction. ( haven`t found that yet).
Hope to get that answer soon.
Is anyone doing this!! Who would tell you. TSM cars are like building a Super Stock. Can`t share all the secrets...RIGHT:eek:
So here it is. Take or Leave it. I just share what I find. Some may find it funny. And some may find it interesting. For me it`s something I just learned and will concider it when going with Aluminum Heads...:rolleyes:
And for those guys who told me this. They are not backyard innovators..

Till next time..
Joe
 
A lot of people run a hotter thermostat with aluminum due to heat transfer. And some don't. ;)

Many imports with aluminum heads have a constant water temp in the 200 range. It's more efficient for fuel economy to keep the heat in. A colder thermostat did nothing for power.
 
The Aluminums would retain more Heat and cause some HP loss.

Hmmm, i always thought Aluminium disapates heat and iron retains heat.
Guys i need a set of ported TA heads, please sell them to me so you can go back to iron heads and make more power.:biggrin:
 
The larger .....

ports and valves may be reducing the intake charge velocity, w/all things being equal.
 
This is my experience ONLY, with Champion irons@ 28lbs peaking to 30lbs i ran 10.20, Champion GN1 ported @ 25lbs i ran 9.94, and street trim boost@ 22lbs i ran 10.16.
 
i know i plan on taking my ported irons into the 9.6-7 range....i too was debating aluminums for awhile but for now i know i can get 140mph out of the irons with some small tweaks so im sticking with them.
 
Back
Top