SBC Afr Heads

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Re: SBC Afr Heads

Post by cspeier » Sun Oct 22, 2017 7:08 pm

RTR-1 wrote:
Sun Oct 22, 2017 6:36 pm
cspeier wrote:
Sun Oct 22, 2017 4:05 pm
Not all 23 degree heads (castings) are created equal....

Isn't all AFR heads cast at Edebrock's foundry?
No idea, I don't work on them.

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Re: SBC Afr Heads

Post by RAMM » Sun Oct 22, 2017 7:41 pm

I've had AFR heads on my flowbench and on the dyno and I don't see how they are all that great. They don't really flow some unfathomable amount and the engines I've tested with them haven't made some inconceivable power. Now I have witnessed some iron heads that have produced WAY more power than the vintage and flow numbers would indicate. The Sportsman II's are very good at making power with some well executed attention. If moving to aluminum is a big deal to you then ditch the Sportsman II's but don't expect a big power increase just because of some lightweight castings. J.Rob
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Re: SBC Afr Heads

Post by Walter R. Malik » Sun Oct 22, 2017 11:06 pm

It seems that just about every aftermarket company somewhat inflates their flow numbers for those people buying the airflow without regard for anything else.

For the 23 degree heads, I really liked the power capability of the G M Performance "fast burn" stuff but, I am sure their is probably better stuff available out there somewhere out of the box.
I have heard some good things about the AFR 227's but, nothing really great.
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Re: SBC Afr Heads

Post by 68post » Tue Oct 24, 2017 2:32 am

Anyone know who has a CNC program for the Sportsman II's ??

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Re: SBC Afr Heads

Post by Carnut1 » Tue Oct 24, 2017 8:44 am

Why cnc? Plenty of excellent head guys on ST that could tune these right up. Post whole combo and what you are looking for as far as output. Thanks, Charlie
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Re: SBC Afr Heads

Post by 68post » Tue Oct 24, 2017 8:38 pm

Carnut1 wrote:
Tue Oct 24, 2017 8:44 am
Why cnc? Plenty of excellent head guys on ST that could tune these right up. Post whole combo and what you are looking for as far as output. Thanks, Charlie
Thanks for the reply. They don't have a home yet, but they were an impulse buy because of very low miles and the previous owner had to have AL heads. (bought for around $200 shipped, w/o exh valves)
I'll start a thread at that time. They definitely need some love bestowed them and I figured iron ports so slow that someone has a favorite program that lets the robot do the job - especially if it's a heavy amount of work (turning these sows ears into silk purses :) ).

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Re: SBC Afr Heads

Post by Carnut1 » Tue Oct 24, 2017 9:50 pm

Depending on what the combo looks like they may not need a ton ground out of them. They can be pretty healthy around 215cc. Thanks, Charlie
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Re: SBC Afr Heads

Post by ZEOHSIX » Tue Oct 24, 2017 10:03 pm

You might want to investigate the 23 degree head Chad offers....they've been know to perform better than AFRs and can be spec'd with good quality valves/hardware.....or you can roll the dice with some parts from India if AFR feels inclined to bargain shop the planet for their parts.

The 195 Eliminators I had made 560HP/500ft/lbs on top of a pretty decent 377cu/in SBC (4.155 bore X 3.50 stroke) wet sump motor had some pretty.decent parts....2925 Edelbrock (slight rework) Holley 750HP, Comp solid roller, T&D shaft rockers, profiled 48lb Scat crank, Manley USA I beam rods, Isky tool room springs with CV Products super lite tool steel retainers and a Xceldyne belt drive.....speed costs money BUT.......RELIABLE SPEED can drastically add to the expenses.....threw away the AFR junk in the heads and ponied up for Manley Severe Duty valves....had to have those custom made....even the Super 7 headlock valve keepers were $96 as I recall (steel not Ti).....if I were building it again....I'd put a set of Profilers on it.

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Re: SBC Afr Heads

Post by 68post » Wed Oct 25, 2017 2:22 am

Carnut1 wrote:
Tue Oct 24, 2017 9:50 pm
Depending on what the combo looks like they may not need a ton ground out of them. They can be pretty healthy around 215cc. Thanks, Charlie
Thanks Charlie, that's very useful info ! Tim

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Re: SBC Afr Heads

Post by G72Zed » Wed Oct 25, 2017 9:51 pm

Steve K wrote:
Sun Oct 15, 2017 9:33 am
Carnut1 wrote:
Sun Oct 15, 2017 8:43 am
Make horsepower or buy horsepower? Expect to have a pro go through those brand new AFR's and check guides, valve seat concentricity and spring load. Just needs to be done. I would buy a cheap electric grinder, speed control and a sharp burr do some metal removal with guidance and then get the iron heads guides, vj, and flat mill, upgrade springs maybe ti retainers and custom cam. Sportsman 2's can make some power. Still way cheaper than new AFR 's. Thanks, Charlie
You're right on this. I ported those Sportsman II's and put them on a 383 with the same cam and made 465 hp on the dyno with the same cam. Other than the weight penalty they can be made to work
x2^^ Yep, that's what I did, bought complete '91 Sportsman II heads used back in 1995,($300) they proved reliable and OK for HP in stock form over many years. I decided to work them over carefully to see what I could get out of them before I pulled the trigger on the AFR's. Up hear in the great white North, those 195 Comp Ported AFR's where like $2,500 with exchange and taxes (2014), so decided to try and "make" HP first.

I was told by more than a few "hot rodders" that they where old and outdated, and a couple of them said they are "door stops".

After my porting work, I had them shaved, and a 3 angle VJ done, then I got them flowed, 2 different benches to be sure, they came in at 252 CFM @ .500 on Intake and 180cfm on exhaust. I used the "AFR" reference for HP per CFM rule, that math said the "potential" HP could be 518, did not believe this number.

I put them on my 327+40 over short block, 10.57cr, 91 pump gas, solid FT crane cam, 252@.050, .510 lift after lash, 112 lsa, ported single plane with 750HP Holley. Made 534 hp at 6,900 and 447 tq at 5,400. The Dyno operator was very surprised at the results to say the least, and so was I.

Just my 0.02 and experience with these heads, as per RAMM's quote, they do perform better than what the flow numbers would indicate.In my case anyway.

PS: I just joined this forum late last year, and this is my first post.

Thanks
G.

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Re: SBC Afr Heads

Post by ProPower engines » Thu Oct 26, 2017 12:31 am

GARY C wrote:
Sun Oct 15, 2017 3:08 pm
Carnut1 wrote:
Sun Oct 15, 2017 8:43 am
Make horsepower or buy horsepower? Expect to have a pro go through those brand new AFR's and check guides, valve seat concentricity and spring load. Just needs to be done. I would buy a cheap electric grinder, speed control and a sharp burr do some metal removal with guidance and then get the iron heads guides, vj, and flat mill, upgrade springs maybe ti retainers and custom cam. Sportsman 2's can make some power. Still way cheaper than new AFR 's. Thanks, Charlie
This thought seems to be reaching the point of urban legend. I am sure that most OTB heads don't have what some think they should have but when you consider the 10's of thousands of OTB heads with thousands upon thousands of miles on them or even worse the millions of mass produced vehicles over with over 300,000 miles on them without an issue you have to wonder would AFR really risk having to replace thousands of heads over something as simple as honing guides?
What do you think happens to the valve seats after a virgin head has been tq-ed and run through a heat cycle?
If you are truly concerned about that then you should run the engine in and do 30 or so dyno pulls and then check all that, other wise you are changing something that is going to change again before it needs to be changed.
Or maybe the pro engine builders just do that for peace of mind.


Gary is correct in saying they change after being run. the OTB heads are bad to start with. I have had no less then 15 customers bring in AFR heads this past year with complaints of valve leakage from the seats not being concentric to the guide center.
I had a customer that was very skeptical and I demonstrated to him what happens when a head is bolted to a block.
he had a questionable set of Afr heads that leaked past the valves on the bench by just pouring some solvent in the ports.
He was flabbergasted to see his new heads that he spent well over $2000 on were that bad.
I disassembled them and checked the run out of the seats and valve seat faces and again WTF did I pay for here.
Now I bolt them to an iron torque plate I use to do VJ's on alloy heads with and preformed the same run out check on the seats and again Holy f*** were they out of wack even more.
Now I am not sure if us guys in the great white north get a different quality level shipped up here but I have never seen a head from them that did not need work OTB.
Like Chad mentioned he don't work on them and I bet for a good reason. ](*,) ](*,)

Mass advertising is how the word gets to the mass's and the more you see a product being advertised or talked about it gives a sense of quality or a poor product. Thats up to the buyer to find out for themself [-o<
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Re: SBC Afr Heads

Post by GARY C » Thu Oct 26, 2017 12:49 am

ProPower engines wrote:
Thu Oct 26, 2017 12:31 am
GARY C wrote:
Sun Oct 15, 2017 3:08 pm
Carnut1 wrote:
Sun Oct 15, 2017 8:43 am
Make horsepower or buy horsepower? Expect to have a pro go through those brand new AFR's and check guides, valve seat concentricity and spring load. Just needs to be done. I would buy a cheap electric grinder, speed control and a sharp burr do some metal removal with guidance and then get the iron heads guides, vj, and flat mill, upgrade springs maybe ti retainers and custom cam. Sportsman 2's can make some power. Still way cheaper than new AFR 's. Thanks, Charlie
This thought seems to be reaching the point of urban legend. I am sure that most OTB heads don't have what some think they should have but when you consider the 10's of thousands of OTB heads with thousands upon thousands of miles on them or even worse the millions of mass produced vehicles over with over 300,000 miles on them without an issue you have to wonder would AFR really risk having to replace thousands of heads over something as simple as honing guides?
What do you think happens to the valve seats after a virgin head has been tq-ed and run through a heat cycle?
If you are truly concerned about that then you should run the engine in and do 30 or so dyno pulls and then check all that, other wise you are changing something that is going to change again before it needs to be changed.
Or maybe the pro engine builders just do that for peace of mind.


Gary is correct in saying they change after being run. the OTB heads are bad to start with. I have had no less then 15 customers bring in AFR heads this past year with complaints of valve leakage from the seats not being concentric to the guide center.
I had a customer that was very skeptical and I demonstrated to him what happens when a head is bolted to a block.
he had a questionable set of Afr heads that leaked past the valves on the bench by just pouring some solvent in the ports.
He was flabbergasted to see his new heads that he spent well over $2000 on were that bad.
I disassembled them and checked the run out of the seats and valve seat faces and again WTF did I pay for here.
Now I bolt them to an iron torque plate I use to do VJ's on alloy heads with and preformed the same run out check on the seats and again Holy f*** were they out of wack even more.
Now I am not sure if us guys in the great white north get a different quality level shipped up here but I have never seen a head from them that did not need work OTB.
Like Chad mentioned he don't work on them and I bet for a good reason. ](*,) ](*,)

Mass advertising is how the word gets to the mass's and the more you see a product being advertised or talked about it gives a sense of quality or a poor product. Thats up to the buyer to find out for themself [-o<
I believe it was Darin Morgan that said when he does heads he wants to remove the very least from the seat possible because they need to be redone after being ran to get them truly consistent.

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Re: SBC Afr Heads

Post by ProPower engines » Thu Oct 26, 2017 1:07 am

I talked with Darin about some issue like this a few years back and he said it is really an issue with heavily ported heads. He told me heads he uses are made with extra material in specific problem locations to help combat the issue of seat distortion after the initial running of any engine they build.

Sort of explains why most street type heads have this issue #-o as they are a 1 head fits all applications kind of deal [-X
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Re: SBC Afr Heads

Post by F-BIRD'88 » Thu Oct 26, 2017 2:37 am

Maybe the cylinder head manufacturers that want to deliver a head that has a advantage would
pre age the heads (run them on a running engine) then touch up the valve job before shipping.

Now the head has done its moving around and is now a more stable constant better performing head.

Is there a market for this?

Is there a method to "pre age" the new head that is not actual running it on a running engine but achieves the same thing? Say bolt the head to a jig and expose it to heat and pressure and vibration and water circulation over many cycles/time to PRE stabilize it by simulating the effect of running it on a running engine.
A power advantage? A power advantage that people will pay for to get a better cylinder head?

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Re: SBC Afr Heads

Post by cgarb » Thu Oct 26, 2017 3:13 am

Yes, there is a market for that. It's the LS1 market. Pull a junkyard core, have it CNC ported and build a performance engine out of it.

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