Rebuild 915 heads or go aluminum?

[496 polara]

For a mild build I would go Sidewinder heads from Todd at Marsh Performance.He can build them mild to wild to suit your needs.
If you are going for a strong effort then TrickFlow or even CNC ported Edelbrock or Stealths would suffice.
How fast you want to go depends on how much $$$ you are willing to spend.

 

[72Duster440]

ALUMINUM! Spent 1k on my Stealth heads (stock shape/appearance), they are much lighter than stock (like 60 lbs) they flow waaaaay better out the box, have smaller chambers, etc... We had them looked over and squared up for like nothing...
In my opinion much more desirable than some super heavy, very needy, 1967 tech...

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What did you need to have done to them? I was looking at them for a while, but have read a lot of bad reviews.

Hotrod did an article a while back comparing them to 915's. They said they were worth the money, but their dyno results showed about a 10 horse and 10 ftlb increase compared to the gasket matched 915's. That's a lot of money for 10 horse.

 

[1970dartcustom]

What did you need to have done to them? I was looking at them for a while, but have read a lot of bad reviews.

Hotrod did an article a while back comparing them to 915's. They said they were worth the money, but their dyno results showed about a 10 horse and 10 ftlb increase compared to the gasket matched 915's. That's a lot of money for 10 horse.

Just had them looked over and squared up... They weigh like 60 lbs less than the stock heads! That's a lot of weight loss... SO that adds into the equation. Also, the newer ones have better parts on them, and are better quality than the older ones... 915's are only good with porting and such done to them, stealth flow better out of the box...
My setup is not finished yet, still doing some electrical...

 

[Tedshredz]

Hey guys, got a few questions.

I recently stuck a 440/727 into my Duster. It runs and drives good, just doesn't have the power I thought it would. I am almost certain its a later year block, and I will verify when I get home tonight. With that being said I think its probably low compression motor. I am going to check cranking compression and leakdown test tonight as well.

After some digging around I found that the 915 casting heads are the most desirable stock head at least if you want to bring up the CR. Talked with my dad and just so happens he has a set. They will need to be gone through and freshened up.

My question is, is it worth the $$$ to rebuild the 915's or go aluminum now? Also should note that I am going to put together a good bottomend from parts we have around. 67 or 68 block, couple different crankshafts to choose from, good rods(cant remember brand) and have some KB10:1 pistons and have some speedpro (I think) 11:1 pistons. Would be buying a camshaft that will work with whatever we decide to build.

Any advice would be greatly appreciated!

I know this has been around for 8 years, and I have the same question today: is it better to go with aftermarket aluminum *(al la www.440Source.com) or find what’s become a bit of a grail in a set of unmolested 915 heads offered for a single year 56 years ago. If I were racing, and to fit into the stock categories, I’d have to stay with the iron. Then there’s the cool factor of find a set and porting them as per David Vizard, and creating a head that might compete with the aftermarket and run with the modified at the track, too.

But, if it were a time thing and I wanted to be up and on the road, the aftermarket would be the way to go, because the back yard gems and junk yard bones have been well picked over in 2024…not to mention there’s lots of junk and failed projects being sold as functional or core quality….so you’d have to know what to look for with the item right in front of you.

 

[33IMP]

I know this has been around for 8 years, and I have the same question today: is it better to go with aftermarket aluminum *(al la www.440Source.com) or find what’s become a bit of a grail in a set of unmolested 915 heads offered for a single year 56 years ago. If I were racing, and to fit into the stock categories, I’d have to stay with the iron. Then there’s the cool factor of find a set and porting them as per David Vizard, and creating a head that might compete with the aftermarket and run with the modified at the track, too.

But, if it were a time thing and I wanted to be up and on the road, the aftermarket would be the way to go, because the back yard gems and junk yard bones have been well picked over in 2024…not to mention there’s lots of junk and failed projects being sold as functional or core quality….so you’d have to know what to look for with the item right in front of you.

Well prices of aftermarket heads have gone up (more than) a bit in eight years, but......
I had a set of iron heads freshened a couple years ago. Paid $900. The catch... they were professionally ported max wedge heads.
I'm guessing it will cost more than that today to freshen 915s. Then you will have heavy, stock flowing heads. Unless you port them, and you know what you are doing. I don't know anybody that ports iron heads for customers anymore, and if I did, you wouldn't want to pay the bill.
So, if it were me, I'd scrape the money together for lighter, better flowing heads for just a few hundred bucks more than old heavy iron.
Unless it was for a valuable, numbers matching restored collector car.... I wouldn't put ten cents into a set of 906s.

 

[MOPARMAGA]

I know this has been around for 8 years, and I have the same question today: is it better to go with aftermarket aluminum *(al la www.440Source.com) or find what’s become a bit of a grail in a set of unmolested 915 heads offered for a single year 56 years ago. If I were racing, and to fit into the stock categories, I’d have to stay with the iron. Then there’s the cool factor of find a set and porting them as per David Vizard, and creating a head that might compete with the aftermarket and run with the modified at the track, too.

But, if it were a time thing and I wanted to be up and on the road, the aftermarket would be the way to go, because the back yard gems and junk yard bones have been well picked over in 2024…not to mention there’s lots of junk and failed projects being sold as functional or core quality….so you’d have to know what to look for with the item right in front of you.

The 440 source head is basically a 915 chamber with big valves and a 906 intake runner that was ported then made into a mold. I've owned a set, they are a little better than an okay head. However I personally would have a machine shop look them over and set the spring up properly and or replace them, touch up the valve job too, they're made and assembled quickly for profit not quality.
I have worked on a couple sets and both have been pretty close but both needed a better valve job for sure.

 

[AndyF]

These days it costs a small fortune to find a good set of cast iron cores and to have them fully rebuilt. Getting cast iron heads ported so they make decent power is going to cost a whole bunch more. The only customers that I've seen spend money on cast iron heads are the resto guys, or the NHRA stock eliminator guys.
20 years ago I tried to build a super nice set of 906 heads. By the time I was finished I had more money invested in them than what a set of aluminum heads cost. And the cast iron heads were still down on power. I haven't messed with cast iron heads since.

 

[1WildRT]

Haven't read any of the responses yet... FWIW I have three sets of 915's... Obviously I like them... That said unless your building an engine that needs to be visually stock I see absolutely no reason to run 915's... Aluminum hands down...

 

[1968rt]

Keep this in mind. If you buy aluminum heads you still have to have them checked out!!! Dont run anything out of the box. I bought my Stealths for $1000 and still had to have $450 worth of work.....recut seats....checking guides.....replacing retainers and locks. Now days with prices up to $1499 then having them corrected we are talking 2k for a set of Stealths, really?? I would see how much work the 915s will be or pay up for better heads like Trick Flows or Indys.

 

[pittsburghracer]

Keep this in mind. If you buy aluminum heads you still have to have them checked out!!! Dont run anything out of the box. I bought my Stealths for $1000 and still had to have $450 worth of work.....recut seats....checking guides.....replacing retainers and locks. Now days with prices up to $1499 then having them corrected we are talking 2k for a set of Stealths, really?? I would see how much work the 915s will be or pay up for better heads like Trick Flows or Indys.

And what you are going to be able to just bolt the TrickFlow or Indy heads on out of the box. Lol. Good luck.

 

[AndyF]

Trick Flow heads are typically ready to use right out of the box. None of the other brands are currently, but things change over time as employees come and go.

 

[pittsburghracer]

Trick Flow heads are typically ready to use right out of the box. None of the other brands are currently, but things change over time as employees come and go.

Typically maybe but are you going to chance it.

 

[66fs]

I'll be running 915 heads on my "68" 383. Stainless valves, milled .020, gasket matched, pocket ported.

 

[Dartswinger70]

Lemme ask this would you go iron for just under a grand or aluminum for $1200 or more...? all things being the same in CFM and just saving the weight?

Personally my whole issue with "go Speedmaster" is if I order them I want to bolt them on and skip the machine shop (which is where Im spending the money with iron)

if I need to send new Speedmaster to the machine shop I dont see it as more than shaving weight for 500 more after the machine shop.

I have a set of SBM 915 Js in the shop right now with the works being done to them(no porting) for $950 out the door just for the backstory.

The one thing that I think is great about the interwebs is there are plenty of people who will tell you how to spend your money

 

[PRH]

Lemme ask this would you go iron for just under a grand or aluminum for $1200 or more...? all things being the same in CFM and just saving the weight?

I have a set of SBM 915 Js in the shop right now with the works being done to them(no porting) for $950 out the door just for the backstory.

Unported J heads aren’t even close in terms of flow to ootb SM heads.
So, all things are not the same.

Of course, this thread is about BB 915 heads.

 

[Dartswinger70]

Unported J heads aren’t even close in terms of flow to ootb SM heads.
So, all things are not the same.

Of course, this thread is about BB 915 heads.

May the fleas of 1000 camels infest your armpits and your arms be too short to scratch...