I agree with this. I think the OP mentioned that his car is just a "street' car, so if it were me, I would just keep the 915 heads, and do a little work on them to work with the cam and intake. No reason to go overboard for a street car, a street/strip car that goes to the track often, or a full bracket car would be a different story obviously.

I like the fact that the stealths are aluminum and you can run 10:1 compression ratio and and it does not detonate. Can’t do that with iron heads and pump gas very easily.

With flow and all other things equal an aluminum head needs almost a point higher compression to equal the power of the iron heads.

Nice replies Guys.

Here in the ‘old country’ we is seen as dynosaurs with our 50+ year old cars.
I remember a guy in the 80’s asking me “why do you put engine management on a model T”?
That’s how he saw us back then and I hate think how they see us in 2021 lol...

So where are we now?

Building a 528ci hemi for a Moparmate and he is talking EFI at me...
I’m thinking iron heads or aluminium heads and he is thinking about engine management...

So what’s right and what’s wrong?

Neither, it’s all about what you is happy with.
Seen a lot of bowed and buggered aluminium heads as a lifelong engineer.
That’s not to say that iron doesn’t go outta shape too...

This extra one point of compression thing haunts me!

So you take off your open chamber 906 and put a closed chamber Eddy head and.

The engine sounds like a bag of nails and wrecks the piston skirts...

Been there done that and I think it’s Tosh (English for trash)...

Nope,,, with pump gas it really hurts the engine so I’m sticking with IRON...

Count me in the group that simply took my Stealths out of the box, changed the valvesprings to the ones that came with my cam. Also added 10* locks, and bolted them onto the car. Went a decade with Zero issues. Finally pulled them a couple of years ago and sent them to MCH for a full CNC port and prep. Everything with that process went great, now flow 320+ (according to MCH). I have never had an issue of any kind with mine.

Not true and if you have documented evidence to state otherwise I'd be happy to see it.

Hotrod ran a comparison of an AL head vs an FE head, they saw nothing to support any of the old wives tales about AL needing more compression, or FE being more sensitive to detonation.

https://www.hotrod.com/articles/ccrp-0602-iron-versus-aluminum-cylinder-heads-test/

What I think, and this is only supposition on my part, is that the reason AL heads got a rep for being more detonation tolerant, or even for making more power, than an iron head is that people were taking iron heads designed in the 50's, 60's or even 70's and comparing them to modern design heads that happened to be made of aluminum. I firmly believe that the combustion chamber design and port improvements account for the differences, not the materials chosen.

A good example of this is sbc vortec head[iron] much better flow and port design.

In NHRA Stock a lot of Mopars changed over to the acceptable aluminum replacements and were very disappointed. Some combos are factored higher with the original iron heads than the aluminum, the chamber CCs must remain the same. Back before all of the aftermarket heads became legal a well known BB Chev engine builder and Stock racer told me the iron heads are faster.

Building to race rules is a whole different animal. You have to meet their rules regardless if that is the most efficient setup. Also, anecdotal evidence, i.e. someone told me, is not documented evidence. I gave you a link to some relevant and documented testing, that is what I am looking for in this regard. Now if you had a dyno run that showed 915 heads made more power than Stealth heads, ALL ELSE being the same, then that would be interesting.

Years ago one of the big name aftermarket head makers ran an add showing something like 50hp gain with their heads over stock heads. If you read the tiny fine print it said compared to stock 305 heads on a 350. LOL, well no chit cherlock as my Dad would have said. Wonder how it compared to stock 350 heads on a 350?

Building to race rules is a whole different animal. You have to meet their rules regardless if that is the most efficient setup. Also, anecdotal evidence, i.e. someone told me, is not documented evidence. I gave you a link to some relevant and documented testing, that is what I am looking for in this regard. Now if you had a dyno run that showed 915 heads made more power than Stealth heads, ALL ELSE being the same, then that would be interesting.

Years ago one of the big name aftermarket head makers ran an add showing something like 50hp gain with their heads over stock heads. If you read the tiny fine print it said compared to stock 305 heads on a 350. LOL, well no chit cherlock as my Dad would have said. Wonder how it compared to stock 350 heads on a 350? [/quote] Here's a good example, A 69 Camaro 396/375 in Stock with auto which is the most popular, is rated at 412 HP with iron heads, the same car everything else equal with identical factory aluminum heads is rated at 405 HP. In NHRA Stock, it's common knowledge that 10K spent for a 3 hundredths gain is a good deal so with money being no object, they can't get the aluminum heads to equal the iron heads all other things being equal. The aluminum head car can run 56 lbs lighter but most guys pull the extra weight to run the iron heads. The same thing with the 62-67 383, 7 HP more for the iron heads and nobody is running the aluminums. That's an extra 80lbs for the 63 383 to pull in H/SA to run the iron heads. The combo's that show more HP for the aluminum heads on the Mopars are rarely built.

Unfortunately Motortrend stops us from viewing all the wonderful info by HotRod!

A great loss to us overseas wannabees...

So, I saw a vid from the man in Canada called Nick.

He did a back to back 'Iron versus Aluminum' hemi dyno run and the ALI heads didn't do very well at all...
Stock heads 'no porting' and both cast by Mother Mopar!

I bet the ALI heads needed 'MORE' compression lol...

Once a myth starts they is hard to break!

My greatest pleasure on my trips to the US of A, was watching MYTHBUSTERS!

Hopefully one day they will do some realtime-useful car stuff like ALI v IRON...

Best myth of ALL time 'BUSTED' by Brandon at 440 source...

Late model iron 440 blocks ARE THINWALL castings...

Why DID Mother Mopar write that in the BIBLE of Mopar Performance???

AND who would take the TAILGATE off the back of their pickups???
All your stuff falls out onto the FREEWAY you JACKASS...

ALTHOUGH i STILL BELIEVE THE 915 IN BOTH BIGBLOCK AND SMALLBLOCK ARE AS GOOD AS IT GETS...
(Oops wrote that with Caplock on)

I have taken the plunge and in the process of building a 413ci 1962 MAX-WEDGE, surely the KING off IRON>>>

Some ifs here to consider. "What ifs" actually. What if the guides in the iron 915 heads are still good? Possible but unlikely But if they are still good that saves about what $300 in machine shop costs? Its possible a good set of street heads can be made from a vintage set. I mean when were talking an honest 350-400 hp home build these heads are more than capable. Factor in a DIYer sensible porting job and you have some really great heads. Just things to at least point out.

If the steel heads don't need guides, and the valves are good to use, having the steel heads cleaned, lap the valves and install the springs needed for your cam is the way to go. If you can do all this yourself all the better, but to find a good set of steel heads is the key. If you have a bare set of heads, that need vales and than need guides, adds up quickly. I had $500 in a repairing of set steel heads I had on car. Broke the motor, bent 7 valves. Had a machine shop plain the heads to clean them up and install 2 guides. My dad did all the other work and installed new valve springs.

I remember reading somewhere, maybe here, maybe in one of the car mags that due to aluminum's ability to dissipate heat better than cast iron, you COULD run more compression. I don't think it said that you HAD to. I think it was said that you could run ABOUT one extra point of compression with the aluminum before you had the detonation issues that you would have had with the cast iron. And I may have misunderstood all of that and gotten it wrong.

I charge 100 for thin wall bronze bronze guides, parts and labor. 360 for clean and mag, guides, comp valve job and cleanup mill, any porting, flow testing or parts are extra. These heads are still worth using IMO.