I wish.....LOL

MOST of the heads compiled in this chart were sent in by potential AFR customers and evaluated at no charge....(some were even purchased retail from various vendors thru a private party so as not to get a set of "ringers"). Obviously that works for the customer (except the part of the sobering flow numbers), and it also provides an oppurtunity for us to see how our product compares to the general cross section of heads available to the public. If any of you are interested in getting something tested you can PM or call me and we can discuss it. Assuming its not a head I have seen three times already, I'm sure we could work something out. It also helps us guage what our customers could potentially see in power improvements moving into an AFR cylinder head which is nice to know if your thinking about dropping a couple of grand on a pair of new heads.

Regarding heads meeting "advertised numbers", I must say the results seem to indicate that it is more the exception than the rule. Some came in with reasonable claimed figures and were pretty close to the mark, others missed by as much as 40 CFM's. That takes "inflated" to a completely different level....the average was probably somewhere in the middle.

Another piece of key information in this list is the size of all the different ports. Cross sectional area is probably more accurate (and more difficult to measure), but port volume is a quick, but pretty good indicator of how efficient the port design is. A more efficient port will have higher airspeed which plays a significant role in power output, torque output, throttle response, and fuel economy (something becoming more of a concern in light of recent gas prices). Who wouldn't want more power AND better fuel efficiency...I know I would.

Who wants to be "Head "V"??

Tony M.

PS....Just wanted to say thanks to the people who have helped provide some of the heads and information for this comparison.

 

Stay tuned Tony...

Ed

 

i agree.i just measured one of the intake ports from my old stg.2 heads that i removed this weekend and it came out to around 230cc's,quite a bit larger than advertised.my new heads,with peak flow being 270cfm,are definately not breaking any records.but the ports are a lot smaller (213cc int.,80cc exh.).with strong low-mid lift numbers and a smaller runner i'm hoping for better average power across the band than my old heads,and should work better with my small cam.

 

So, are the heads that have been tested freshly prepared or are they carboned up and used?

Richard

 

Hello Richard...

I've been waiting for that question....certainly a valid point I thought someone might have hit me up on already. Many of the heads tested were either never run or had very low miles end easily cleaned up with a scotch brite pad, some WD 40, and a little elbow grease. Some of the heads with more miles on them took more time to clean and on a few of them I carefully (and lightly) sandrolled the exhaust with a fine grit cartridge roll to get them clean (remove the carbon build-up)....the exhaust side is always a little tougher to get clean on the stuff thats been run awhile, but the intakes normally come clean with a scotch brite pad. I would make sure I just removed the built up carbon and not alter the shape in any way. Not to difficult to do really with the right sandroll and some light pressure, just takes a little time.

Bottom line, I spent the time to make sure that all the heads in question were being tested on an even playing field, essentially there were no advantages or disadvantages of new heads versus used heads. I also failed to mention that I wire wheeled all the valves on the used heads so the valve heads were perfectly clean and would not have a negative impact on flow from carbon and oil buildup etc. As I mentioned much earlier in this thread, this information was primarily for AFR R&D specifically to see how our heads compared to the vast array of ported factory pieces currently on the market. Trying to skew the numbers in our favor would have only amounted to cheating ourselves out of the proper information and comparisons.

Sorry for the long winded answer but I wanted people to be clear that every head I have tested has had an opportunity to look its best under similar test conditions as the others in the test. Truth be told the last head I flowed ("U") was used and needed some cleaning up and I wasnt really up for it but just couldn't bolt it up to the bench knowing the numbers would be tainted from the carbon and oil build-up etc., so I put it off till I had the time and ended up cleaning and flowing it another day.

Tony M.

 

Thanks for clarifying Tony. This thread is a nice refrence. Thanks for posting it.

Richard

 

After pointing out that you clean the heads I was wondering how much cardbon build up effects a heads performance? A few CFM's? Is there a way you could test a used set, then clean them to see if it makes a huge difference?

 

Are any of these heads All-Pro cnc hand ported don't want to know which number just if there is a possibility? Big deciding factor in up coming head purchase.

 

Hopefully Tony can comment with his experience on the effects of carbon buildup on the seats, valves and chambers and how it relates to airflow. I asked the question not as a jab or a barb, but to put to rest the thoughts that a variable such as dirt or carbon is accounted for in making direct comparisons. My experience is that high flowing heads show great sensitivity in the valve seat's curtain area and if any heavy carbon buildup exists directly before or after that curtain area there's virtually always a loss in flow. This would account for one of several reasons why racing heads are refeshed on a regular basis. It would also be helpful if members who post airflow data on their heads comment if the heads and valves are used (uncleaned), new or refreshed heads. (It's a question that always lingers in the back of my mind). It really can make a big difference in some cases. As Tony mentioned above, he spent the time to be sure that dirt and carbon was not a factor and I'm ok with that. Believe me, the time spent cleaning and prepping the test ports adds a lot of time spent on leveling the playing field.

Respectfully,

Richard

 

Way back when I did a test on a BBC head that was pretty dirty with a fair amount of crud built up on the backside of the valve etc., and I was surprised that after I cleaned it up the results weren't a whole lot different (considering how carboned up it was). If my memory serves me well I want to say the head flowed 3-7 CFM better after I cleaned it up (both ports, the chamber, and the valves). However, considering this was a BBC head with large valves, I'm thinking it might not be as sensitive as a smaller port might be. I would guess that an average condition used "LS" head would lose somewhere around 4-6 CFM's depending on the lift point in question versus the same head perfectly clean. The next used head I get in that has a reasonable amount of carbon build-up on it I will test before and after and post the results. The other thing that needs to be considered is the newer fuel injected motors of today are MUCH cleaner when they come apart (versus say a carburated performance engine)...If you would have seen how dirty that BBC head was you would have guessed a 15 CFM loss!

BigNuts, regarding the AllPro head, I would tell you that as of right now I haven't had the opportunity to flow one (to new....not many out in circulation yet). What I have heard (and read) is the All Pro starts as cast at 230 cc's and flows between 280 and 300 CFM depending on who you want to believe. I don't know your intended application but I would imagine the All Pro would be getting fairly sizable in "ready to run" trim. If your building something for a dual purpose car with a cam around .600 lift, the size (volume and cross section) and airflow figures the AFR 225's put up are a tough combination to beat....especially for the money spent. I would imagine you would have easily cleared 3K when the smoke clears on the All Pro build.

Regards,
Tony

 

I wonder how the Edlebrock 203CC heads are gonna stack up...

 

I'm more than up for testing a pair if anyone gets their hands on them

 

you like trouble don't you?

everybody wants to know what they will do against yours. and atleast half of them will scream fowl if yours are better!

p.m me when you find out.....

 

Well Dave S. at Edlebrock tells me there at least 4 months away...They are still working on them from what I've gathered and what I was told is,"They'll come out when they work as good as the OTHER guys heads"

 

And we are back to the top once again.....

Just flowed another head I wasn't initially going to put on the "list" but after seeing finished volumes on both intake and exhaust I felt there was no reason it shouldn't be there. It is one of the less expensive alternatives on the market currently. While the intake port wasn't much different (flow wise) than a lot of other "Stg II ish" heads, the exhaust was quite a bit off (I flowed two intakes and two exhausts just to be sure the numbers were representative. They were both extremely close to one another and YES, the exhaust was flowed with the same pipe as the others....1.875" curved like a typical header).

Thanks guys...

Tony M.

 

Tony, I know you been asked a million times and pm'd to death about it. But...I gotta know where I can get, who sells, or any info on, those 225's heads listed at the bottom of each respective list. Those appear to be a wise investment, if I know who makes them, or ports them then I can get some info on combustion chamber sizes and the likes.



i Smilies on!

 

Your last set of flow numbers look a lot like what this member experienced in this thread:https://ls1tech.com/forums/generation-iii-internal-engine/351379-if-you-bought-prc-heads-considering-check-out.html

Here's a little of what he found:
Those numbers look surprisingly similar to Tony's latest results. Could they be the same brand of head?

 

What I think is strange is the flow #'s from the other post claim to be from a local bench. If this is the same results & the same cylinder head then we are not getting honest information. Who really flowed what?!!?!?

 

I am copying my own response regarding this situation from another thread just to also end the controversy on this thread as well....I want to keep this thread as informative as possible without all the typical Internet BS.


[QUOTE]
Lets put this to bed right now....

I did flow the heads in question and I also requested long before actually having seen them that I specifically didn't want to be involved in any potential "drama" after the fact, (assuming the results I gave him wasn't to his liking).

Regarding "having an interest in these heads flowing poorly", I think the implication is poor. These heads flowed exactly what was posted (on our equipment)....I thoroughly checked (and poured) two different ports just to make sure. There wasn't barely a CFM between them on both the two intakes I tested as well as the exhaust and the cc's were the same.....very consistant.

I don't have any interest in getting pulled in to this controversy, and Matt was simply covering for me because he knew I didn't want to be involved but obviously that doesn't seem to be possible any longer.

Jason, it's good that your stepping right up to the plate and trying to get your customer handled, but trust me the results posted on THAT particular set are valid and would be repeatable an another Superflow bench using the same 3.900/4.125 fixturing, exhaust tube, etc. I spot checked a production 205 a few hours later that went 297/232 with all the same equipment.

If you want to PM or call me feel free to do so....I would be more than happy to discuss any of the testing.

Thanks,
Tony M.
[QUOTE]

 

I will be contacting you Monday morning Tony & I hope that you read my other post. I would like for you to test a set of heads that we now cnc in house. If we are going to compare cylinder heads I would like for it to be a cylinder head that was actually cnc'd, finished & flow tested here

Jason
Texas Speed