AT Racing World heads? (Or other "cheap" brands...)

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This is the reason I started this thread. Few people seem to really have anything backing claims for either side. That video was the first one to pop up with any kind of real "data" about them which is why I shared it. Are there better heads out there? Most likely. Will these perform well enough for a bunch of people? Maybe. Are they better than some? Hopefully. What I'm hoping is that we can hear, and maybe see "data" to back it, testimonials about these vs "spend the money and buy "X" brand" that is so prevalent in so many places. For a good number of us, money is a factor when tearing into a project like this. So the bottom line is will these (or any other "budget" piece) be worth the money up front? So far, I think they have a good possibility. But I'd like to hear from someone - anyone - who dove into things like this to hear how they worked out for them.

Edit: changed my wording. I initially said "no one seems to really have anything...." when that's not entirely true. There are a couple posts in this thread alone.
 
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Hi guys,
I finally decided to buy a new pair of aluminium cylinder heads. I saw in your recommendations heads for 800 or maybe 600 usd. If I buy the olds 351 cast irons with 50 years plus the porting work, the difference with this new heads maybe will be around 200 usd??
I found a really good article comparing the E7, GT40, GT40p with the new ones. Somebody knows where to get the specifications intake port, combustion chamber, intake valve and exhaust valve for the 289, 302 and 351? I think will be a whole comparation.
Now the question is how much intake port it is neccesary for a 347? From 170? 180?
Just a part of the article:
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Port size isn't really the only determining factor with heads, although it does play a big role. In my comparisons, I found that the ProMaxx head flowed better than the Edelbrock Performer RPM with the same valve size and a larger advertised port size.
Edelbrock heads advertise 190cc intake ports whereas the ProMaxx heads advertise 180cc intake ports.

Edelbrock numbers posted on Jeg's website:

Valve LiftIntakeExhaust
.100''7057
.200''128104
.300''183142
.400''219163
.500''251170
.600''255174
.700''246175
Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28'' H2O


ProMaxx numbers from their website:

Flow Data @ 28″ water
lift100200300400500550600
Int70136192233257267267
Ext66118152176190195199

So, on paper, the ProMaxx are better flowing heads, especially on the exhaust side where small Fords really need the help.

Remember, when selecting a camshaft you'll want to be mindful of your flow numbers as explained in this video:


View: https://youtu.be/JPAeepqrY-0


I hope all of this helps!
 
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There is something that I don't know about the 347 stroker kit, it is the piston head volume. I guess will be the holes volume for the valves right?
I decided to buy my 347 stroker kit with Summitracing, for under 1000 usd there are two brands Scat and Eagle Street.
If I compare this two kits Eagle Street have +5.00cc piston head volume and Scat +11.00cc, what that means? It is relavant for the heads?
 
I'm open to changing my mind.
Could you provide links to the results from you and members here?
Sure, I dont have any quantifiable data yet as I am still buttoning mine up but @KZGUNS has a set of them on his car.

As an aside I have customers using the Ported versions [205-225] on turbo 351's and running down in the 8's range shifting gears.
 
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I'm more than happy with my promaxx heads. The local guy around here that ports everyones heads (not just some guy, he's a pro) looked them over and thought they were very good. Castings look much better than edelebrock heads. I was very impressed. Check your springs if you get them as we thought they were a bit light. They are performing good for me on a stock bottom end with a blower at around 10psi. I will be doing a new 347 bottom end this winter. I may have them ported a bit, although the guy said they dont need much work to improve whats already there.
 
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There is something that I don't know about the 347 stroker kit, it is the piston head volume. I guess will be the holes volume for the valves right?
I decided to buy my 347 stroker kit with Summitracing, for under 1000 usd there are two brands Scat and Eagle Street.
If I compare this two kits Eagle Street have +5.00cc piston head volume and Scat +11.00cc, what that means? It is relavant for the heads?
at zero deck with 60cc chambers 11cc pistons will get you about 9.9:1 compression and 5cc about 10.6:1 there is a calculator on summit you can use
 
If the kit is N/A is should [not] be forged.

Don't get hung up on forged pistons. Just about every other kind of piston seals better than forged.

What you [should] get hung up on is ensuring it is correctly tuned once it's all together.
 
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If the kit is N/A is should [not] be forged.

Don't get hung up on forged pistons. Just about every other kind of piston seals better than forged.

What you [should] get hung up on is ensuring it is correctly tuned once it's all together.
You are right! What do you think about this combo?
347 stroker kit Eagle Street: https://www.summitracing.com/parts/esp-b16422la030/make/ford
Promaxx heads probably
Camshaft TBD
750 Holley
Tremec T5 Mustang '95
Rear end 8.8" Mountaineer posi + 3.73
 
I don't think it sounds too bad for a "budget" 347.....

Now if you were going for broke as far as horsepower is concerned, that would probably be a different story. But then again it wouldn't be a "budget" build..... :shrug:
 
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