Now.... to only put a name to the "letters". 
Finally, a comprehensive head test....
Thread Starter
Safety Car
Joined: Oct 2001
Posts: 3,504
Likes: 25
From: Insert Wittty Comment here
Finally, a comprehensive head test....
I tried to get this done about 3 yrs ago... I tried to solict support for getting sets of each vendors heads together, and put them on the same bench on the same day, with the same operator.
My hope was to try to eliminate some of the "happy" numbers out there and get some more realistic numbers on what the average set of heads you buy from the vendor flow.
The obvious concerns were getting a set of "ringers" that were "tuned up" for a test. Well, someone did it for me. That was Tony Mamo. If it were me (since I'm not a shop, and I don't sell heads, etc...) I was actually going to post whose heads did what. In the case of Tony, understandably, he can't. I understand and respect his decision not to post names. I think in his case, taking the high ground and not posting was the best thing he could have done.
The results weren't suprising IMHO. It may be to some. But its in line with what a lot of us have seen.
Anyhow, I'm sure this will generate some discussion... Enjoy...
http://www.ls1tech.com/forums/showthread.php?t=317323
Bo White posted some good follow up information...
My hope was to try to eliminate some of the "happy" numbers out there and get some more realistic numbers on what the average set of heads you buy from the vendor flow.
The obvious concerns were getting a set of "ringers" that were "tuned up" for a test. Well, someone did it for me. That was Tony Mamo. If it were me (since I'm not a shop, and I don't sell heads, etc...) I was actually going to post whose heads did what. In the case of Tony, understandably, he can't. I understand and respect his decision not to post names. I think in his case, taking the high ground and not posting was the best thing he could have done.
The results weren't suprising IMHO. It may be to some. But its in line with what a lot of us have seen.
Anyhow, I'm sure this will generate some discussion... Enjoy...
http://www.ls1tech.com/forums/showthread.php?t=317323
Originally Posted by Tony Mamo @ AFR
Hey Guys...
Seems I have continuously gotten flack in the past for questioning some of the larger flow numbers that casually get thrown around the internet. At times I have advised getting them independently flow tested, even offered to test a few etc., and usually end up getting bashed for being "negative" or worse. Perhaps if any of you had the chance to walk a mile in my shoes you might understand why I question the results and why you should to. First off, this information isn't aimed at anyone or any shop for that matter, nor are we "above the law"....feel free to double check our advertised figures as well. The information I have compiled for you is basically the bulk of the larger factory ported LS heads I have had the opportunity to flowtest on AFR's equipment over the last 12-18 months. For that matter, some of the information you will see might have been from the very set of heads a few of you sent in for us to flowtest for you. No names will be mentioned so don't ask, but you better believe that a lot of these heads had much sexier #'s on paper (advertised)....Take this info for what it's worth, throw it in the garbage, call it BS, or possibly have an open mind and pick up something that might help you down the road.
While big flow numbers are certainly more attainable with larger volume ports, getting those kinds of numbers still doesn't come easily....especially in a "production" environment. Any highly competent cylinder head shop can certainly produce good or great results on a pair of heads they invested 50-100 hours into, but is the average Joe actually receiving a comparable set of heads with the same results for a few thousand dollars? Maybe...maybe not
Here is a compilation of some of the larger stuff I have personally flowtested and documented....I didn't bother with the smaller and medium sized stuff I have seen because most of those numbers weren't even in the hunt. Of course I have not had the opportunity to test and flow everyone’s product and a claim like that would be ridiculous, but I have seen quite a few and the flow chart below covers the BEST of what I have seen come across our flow equipment. Keep in mind guys, this IS an “apples to apples” situation, as all of these cylinder heads were flowtested on the exact same equipment with the exact same fixtures, radius plates, flow tube, etc.
For all of the guys that like to crunch numbers, this information should keep you busy for awhile.
All numbers recorded utilizing 4.125 bore unless otherwise noted.
“T” indicates turbulent and could not record any data
“Stg 3” heads were heads that I knew were advertised as such. Others might have been “Stg. 3” but I only labeled heads I was sure of.
INTAKE FLOW
Head…………Int. Valvelift…………………..........Runner
…..….200….300….400….500….550….600…….Volu me…………Comments……….
“A”….136….199….257….294….305….313………232 cc’s
“B”….134….195….239….267….280….289………229 cc’s
“C”….131….189….240….275….287….282………221 cc’s…(LS1 castings)
“D”….141….206….259….291….303….313………231 cc’s
“E”….145….203….253….295….309….321………246 cc’s….Stg 3
“F”….141….206….263….300….315….332………245 cc’c….Stg 3 (Best peak)
“G”….135….201….260….304….316….”T”………239 cc’s……Stg 3
“H”….140….211….260….285….286….287………243 cc’s……Weak for size
“I”…..137….207….252….290….306….318………242 cc’s……Stg 3
“J”.….126….186….231….263….277….290………228 cc’s
“K”….121….190….246….278….293….306………230 cc’s
“L”….146….208….264….301….314….323………237 cc’s.Stg.3 (good overall)
“M”…137….207….252….290….306….318………242 cc’s……Stg 3
“N”….136….190….249….288….301….312………241 cc’s……Stg. 3
AVG..136….200….252…..294….300….308………237 cc’s
AirFlow Research #’s
205….145….210….257….290….301….308………205 cc’s...(205 w/ 4.125 #’s)
225….151….221….270….306….315….322………229 cc’s
EXHAUST FLOW w/ 1.875 pipe (curved to simulate header)
Head………….Exhaust Valvelift…………………..Runner
……...200….300….400….500….600............ Volume
“A”….113….150….180….208….230…………….84 cc’s
“B”….107….147….196….218….228…………….85 cc’s
“C”….107….153….184….205….217…………….82 cc’s
“D”….112….165….195….215….228…………….86 cc’s
“E”….111….156….202….235….246………...…88 cc’s
“F”….126….170….204….226….236…………….85 cc’s
“G”…117….164….201….229….242………………87 cc’s
“H”…113….156….189….221….231………………85 cc’s
“I”…..114…145….179….211….237………………87 cc’s
“J”…..97….133….166….193….213………………89 cc’s……Very weak for size
“K”….117…157….194….218….228………………83 cc’s
“L”….114….155….214….238….252……………..90 cc’s……Big, but good #’s
“M”…120….177….219….240….251……………..87 cc’s….....good #’s
“N”….105….144….177….208….222……………..89 cc’s……Very weak for size
AVG...112….155….193….219….233…………….86 cc’s
AirFlow Research #’s
205….118….171….206….226….240……………..84 cc’s
225….120….180….220….241….250……………..85 cc’s
What's interesting to note is how well the AFR 205's faired among a group of cylinder heads that have a huge advantage in port volume. It becomes a little clearer why the 205 has consistently put up good numbers on the dyno and great results on the street.
Hope you guys enjoyed the data....It represents quite a bit of time invested.
Regards,
Tony Mamo
Seems I have continuously gotten flack in the past for questioning some of the larger flow numbers that casually get thrown around the internet. At times I have advised getting them independently flow tested, even offered to test a few etc., and usually end up getting bashed for being "negative" or worse. Perhaps if any of you had the chance to walk a mile in my shoes you might understand why I question the results and why you should to. First off, this information isn't aimed at anyone or any shop for that matter, nor are we "above the law"....feel free to double check our advertised figures as well. The information I have compiled for you is basically the bulk of the larger factory ported LS heads I have had the opportunity to flowtest on AFR's equipment over the last 12-18 months. For that matter, some of the information you will see might have been from the very set of heads a few of you sent in for us to flowtest for you. No names will be mentioned so don't ask, but you better believe that a lot of these heads had much sexier #'s on paper (advertised)....Take this info for what it's worth, throw it in the garbage, call it BS, or possibly have an open mind and pick up something that might help you down the road.
While big flow numbers are certainly more attainable with larger volume ports, getting those kinds of numbers still doesn't come easily....especially in a "production" environment. Any highly competent cylinder head shop can certainly produce good or great results on a pair of heads they invested 50-100 hours into, but is the average Joe actually receiving a comparable set of heads with the same results for a few thousand dollars? Maybe...maybe not
Here is a compilation of some of the larger stuff I have personally flowtested and documented....I didn't bother with the smaller and medium sized stuff I have seen because most of those numbers weren't even in the hunt. Of course I have not had the opportunity to test and flow everyone’s product and a claim like that would be ridiculous, but I have seen quite a few and the flow chart below covers the BEST of what I have seen come across our flow equipment. Keep in mind guys, this IS an “apples to apples” situation, as all of these cylinder heads were flowtested on the exact same equipment with the exact same fixtures, radius plates, flow tube, etc.
For all of the guys that like to crunch numbers, this information should keep you busy for awhile.
All numbers recorded utilizing 4.125 bore unless otherwise noted.
“T” indicates turbulent and could not record any data
“Stg 3” heads were heads that I knew were advertised as such. Others might have been “Stg. 3” but I only labeled heads I was sure of.
INTAKE FLOW
Head…………Int. Valvelift…………………..........Runner
…..….200….300….400….500….550….600…….Volu me…………Comments……….
“A”….136….199….257….294….305….313………232 cc’s
“B”….134….195….239….267….280….289………229 cc’s
“C”….131….189….240….275….287….282………221 cc’s…(LS1 castings)
“D”….141….206….259….291….303….313………231 cc’s
“E”….145….203….253….295….309….321………246 cc’s….Stg 3
“F”….141….206….263….300….315….332………245 cc’c….Stg 3 (Best peak)
“G”….135….201….260….304….316….”T”………239 cc’s……Stg 3
“H”….140….211….260….285….286….287………243 cc’s……Weak for size
“I”…..137….207….252….290….306….318………242 cc’s……Stg 3
“J”.….126….186….231….263….277….290………228 cc’s
“K”….121….190….246….278….293….306………230 cc’s
“L”….146….208….264….301….314….323………237 cc’s.Stg.3 (good overall)
“M”…137….207….252….290….306….318………242 cc’s……Stg 3
“N”….136….190….249….288….301….312………241 cc’s……Stg. 3
AVG..136….200….252…..294….300….308………237 cc’s
AirFlow Research #’s
205….145….210….257….290….301….308………205 cc’s...(205 w/ 4.125 #’s)
225….151….221….270….306….315….322………229 cc’s
EXHAUST FLOW w/ 1.875 pipe (curved to simulate header)
Head………….Exhaust Valvelift…………………..Runner
……...200….300….400….500….600............ Volume
“A”….113….150….180….208….230…………….84 cc’s
“B”….107….147….196….218….228…………….85 cc’s
“C”….107….153….184….205….217…………….82 cc’s
“D”….112….165….195….215….228…………….86 cc’s
“E”….111….156….202….235….246………...…88 cc’s
“F”….126….170….204….226….236…………….85 cc’s
“G”…117….164….201….229….242………………87 cc’s
“H”…113….156….189….221….231………………85 cc’s
“I”…..114…145….179….211….237………………87 cc’s
“J”…..97….133….166….193….213………………89 cc’s……Very weak for size
“K”….117…157….194….218….228………………83 cc’s
“L”….114….155….214….238….252……………..90 cc’s……Big, but good #’s
“M”…120….177….219….240….251……………..87 cc’s….....good #’s
“N”….105….144….177….208….222……………..89 cc’s……Very weak for size
AVG...112….155….193….219….233…………….86 cc’s
AirFlow Research #’s
205….118….171….206….226….240……………..84 cc’s
225….120….180….220….241….250……………..85 cc’s
What's interesting to note is how well the AFR 205's faired among a group of cylinder heads that have a huge advantage in port volume. It becomes a little clearer why the 205 has consistently put up good numbers on the dyno and great results on the street.
Hope you guys enjoyed the data....It represents quite a bit of time invested.
Regards,
Tony Mamo
Originally Posted by Bo White
Lets add a little math to this:
INTAKE
head - average #s - average #s per cc
A - 250.67 - 1.0804
B - 234 - 1.0218
C - 234 - 1.0588
D - 251.17 - 1.0916
E - 254.33 - 1.0339
F - 259.5 - 1.0592
G - 243.2 - 1.0176
H - 244.8 - 1.0075
I - 251.67 - 1.0399
J - 228.8 - 1.0036
K - 239 - 1.0391
L - 259.3 - 1.0942
M - 251.67 - 1.0399
N - 246 - 1.0207
Mine222.6 - 1.0211 (3.900 fixture)
205 251.83 - 1.2284
225 264.17 - 1.1535
EXHAUST
A - 176.2 - 2.0976
B - 179.2 - 2.1082
C - 173.2 - 2.1122
D - 183 - 2.1279
E - 190 - 2.1591
F - 192.4 - 2.2635
G - 190.6 - 2.1908
H - 182 - 2.1412
I - 177.2 - 2.0368
J - 160.4 - 1.8022
K - 182.8 - 2.2024
L - 201.4 - 2.2378
M - 201.4 - 2.3149
N - 171.2 - 1.9236
Mine173.4 - 2.1146 (3.900 fixture)
205 192.2 - 2.2881
225 202.2 - 2.3788
Average #s are just that, average #s per cc is my way of seeing how effiecient that port is.
INTAKE
head - average #s - average #s per cc
A - 250.67 - 1.0804
B - 234 - 1.0218
C - 234 - 1.0588
D - 251.17 - 1.0916
E - 254.33 - 1.0339
F - 259.5 - 1.0592
G - 243.2 - 1.0176
H - 244.8 - 1.0075
I - 251.67 - 1.0399
J - 228.8 - 1.0036
K - 239 - 1.0391
L - 259.3 - 1.0942
M - 251.67 - 1.0399
N - 246 - 1.0207
Mine222.6 - 1.0211 (3.900 fixture)
205 251.83 - 1.2284
225 264.17 - 1.1535
EXHAUST
A - 176.2 - 2.0976
B - 179.2 - 2.1082
C - 173.2 - 2.1122
D - 183 - 2.1279
E - 190 - 2.1591
F - 192.4 - 2.2635
G - 190.6 - 2.1908
H - 182 - 2.1412
I - 177.2 - 2.0368
J - 160.4 - 1.8022
K - 182.8 - 2.2024
L - 201.4 - 2.2378
M - 201.4 - 2.3149
N - 171.2 - 1.9236
Mine173.4 - 2.1146 (3.900 fixture)
205 192.2 - 2.2881
225 202.2 - 2.3788
Average #s are just that, average #s per cc is my way of seeing how effiecient that port is.
Melting Slicks
Joined: Dec 2003
Posts: 2,857
Likes: 2
From: pawleys island sc
I'm noy qualified to say which heads are "the best", but in my opinion Tony Mamo is one of "the best" members of this forum - the guy has been nothing but helpful to anyone who ever asked for his help and I believe he's truly a "straight shooter".
Former Vendor
Joined: Mar 2004
Posts: 1,518
Likes: 7
From: Valencia CA
Originally Posted by kumar75150
AFRs are nice but not top of the line IMO. I wonder why people like Cartek are still using their own ported heads on their all out packages.
Funny you should post because I offered you a chance firsthand to prove your theory and when the smoke cleared you never sent me the heads, nor made any follow up contact with me. I was quite disappointed how the whole situation panned out. Ironically, it was that situation (on LS1 Tech) which prompted me to start gathering all my data that you see presented above.
As far as why some other shops choose to endorse or not endorse AFR products....have you even considered the fact that one of the reasons could be simple economics? Why does one shop use Lunati cranks and another shop use Callies? There both good crank manufacturers...I'm sure they each have their reasons why they choose one over the other. There is plenty of product (cylinder heads) and shops to go around. The information I have presented you guys with is simply that...information. Its not going to convert a fan of Head Shop "A" over to AFR. It might be food for thought though for someone considering all of his possibilities...
Also...look over the test results....The AFR 225's aren't the highest flowing heads on the list, and some of the other heads you see featured have good flow numbers as well, but put together just about any .600 ish lift engine combination and my money is on the 225's coming out on top....this is my opinion of course and we are all entitled to that. There is alot more to making power than just big peak numbers and most of you already know that. We will soon see alot more 225 headed combo's (including a 383 buildup currently on deck that I am personally involved in) hitting the street and the track in the following months. I'm hoping the results will speak for themselves.....stay tuned.
Tony M.
Last edited by Tony Mamo; May 6, 2005 at 09:22 PM.
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