Interesting Flow Data....(Long thread)
08-30-2007, 02:27 PM
#241
Originally Posted by 99blancoSS
Tony did you add the new data from the worked over 205's that Patrick and I have for comparison?
Chris,
Your reworked 205's (similar to Pat g. and a few others I have helped) are kick *** and would hold there own in this company in spite of their much smaller port but of course wont have the big sexy number on the intake side at .500 +
I may post the numbers anyway and make the footnote about the small runner and the fact they were tested on a smaller bore diameter as well, both of which puts them at a disadvantage in this group of heads. All the other tests were conducted on a 4.125 bore and most of the intake runners are over 230 cc's (BIG difference is cross sectional area).
Thanks,
Tony
08-30-2007, 06:19 PM
#243
TECH Enthusiast
Join Date: May 2007
Posts: 538
Likes: 0
Received 0 Likes
on
0 Posts
I keep seeing this mention of the AFR being such a small port. Having actually seen a set the cross section was as big or bigger then some of the competitors supposedly larger 215 offerings. Is this due to the fact that the port is overall shorter due to the factory valve angle and on top of that are their ports bigger in terms of volume only becuase of the extra length the rolled valve angle adds ? got some cross sectional data to go with these port sizes ?
Originally Posted by Tony Mamo @ AFR
Shiznitz....Thanks for chiming in with some other "real world" independent data. As you know I am patiently awaiting your dyno and track results.
Chris,
Your reworked 205's (similar to Pat g. and a few others I have helped) are kick *** and would hold there own in this company in spite of their much smaller port but of course wont have the big sexy number on the intake side at .500 +
I may post the numbers anyway and make the footnote about the small runner and the fact they were tested on a smaller bore diameter as well, both of which puts them at a disadvantage in this group of heads. All the other tests were conducted on a 4.125 bore and most of the intake runners are over 230 cc's (BIG difference is cross sectional area).
Thanks,
Tony
Chris,
Your reworked 205's (similar to Pat g. and a few others I have helped) are kick *** and would hold there own in this company in spite of their much smaller port but of course wont have the big sexy number on the intake side at .500 +
I may post the numbers anyway and make the footnote about the small runner and the fact they were tested on a smaller bore diameter as well, both of which puts them at a disadvantage in this group of heads. All the other tests were conducted on a 4.125 bore and most of the intake runners are over 230 cc's (BIG difference is cross sectional area).
Thanks,
Tony
08-30-2007, 06:49 PM
#244
Originally Posted by LS1curious
I keep seeing this mention of the AFR being such a small port. Having actually seen a set the cross section was as big or bigger then some of the competitors supposedly larger 215 offerings. Is this due to the fact that the port is overall shorter due to the factory valve angle and on top of that are their ports bigger in terms of volume only becuase of the extra length the rolled valve angle adds ? got some cross sectional data to go with these port sizes ?
The fact a certain head has a valve angle of 11' or 13.5 degrees means nothing....its where you position the valve in the chamber (fore and aft) that will make a larger difference and once again its nominal in most cases anyway. Why quote volume? Because volume is the quickest and easiest way to compare runner size and cross sectional area. You need a scanned digitized surface to accurately quote minimum cross sectional area and that's not going to happen unless you digitize every head that crosses our flowbench. Sure....within a 5cc difference a comparison of minimum cross sectional area might go one way or the other (the larger volume head could have a smaller minimum cross section) but the difference once again wouldn't likely be much anyway. For the most part and speaking in generality, a head with more than a 5cc advantage will likely have a greater minimum cross sectional area, and a head with more than 10 cc's of an advantage will VERY likely have a larger minimum cross section (probably 99% of the time).
Our 225 head usually cc's in the high 220's....looking over the list of heads in that cross section, that type of intake volume represents less than the average in the group (on the small side) yet even out of the box they flow even with, or better than, most of the larger (and much larger) cylinder heads in my database. That can only happen with a well shaped efficient port (and chamber) design which promotes high airspeed inertia aiding in good cylinder fill, less reversion issues, and a host of other positive side benefits.
By the way I mentioned ET purely because they have the most rolled over cathedral port opening at 11' and I have seen a handful of their product (which is very impressive) next to our own.
Hope this info helps...
Tony
Last edited by Tony Mamo @ AFR; 08-30-2007 at 07:31 PM.
08-31-2007, 12:25 PM
#246
TECH Enthusiast
Join Date: May 2007
Posts: 538
Likes: 0
Received 0 Likes
on
0 Posts
Reading this sort of makes me wonder how it is exactly that you measure port cross section?. I have alway looked at port cross section from the viewpoint as well as most others as the opening of the primary portion of the runner itself. the bowl area sort of has to be large. With the shape change the runner undertakes there if you didn't make the bowl area large enough it would flat out kill the short side turn.
Can you post upthe runner opening sizes ? easy enough to measure and most port usually only expand from that point forward if not tapper down but its a fiarly consistent measure of cross section.
Can you post upthe runner opening sizes ? easy enough to measure and most port usually only expand from that point forward if not tapper down but its a fiarly consistent measure of cross section.
Originally Posted by Tony Mamo @ AFR
The whole rolled valve angle versus cc relationship is a little exaggerated. In fact (as an example) the 11 degree ET 215 head is much closer to the cross section of our 225 (in the bowl area) than a 205. Meaning you might expect looking at the numbers that the cross section would be more in the middle (a little larger than our 205 and a little smaller than our 225), or even closer to our 205 product based on some misnomers floating around the Internet, but in reality it is actually very close to our 225 offering (and alot larger than our 205). Note that there are no special tools required to see this....it's very visible to the naked eye.
The fact a certain head has a valve angle of 11' or 13.5 degrees means nothing....its where you position the valve in the chamber (fore and aft) that will make a larger difference and once again its nominal in most cases anyway. Why quote volume? Because volume is the quickest and easiest way to compare runner size and cross sectional area. You need a scanned digitized surface to accurately quote minimum cross sectional area and that's not going to happen unless you digitize every head that crosses our flowbench. Sure....within a 5cc difference a comparison of minimum cross sectional area might go one way or the other (the larger volume head could have a smaller minimum cross section) but the difference once again wouldn't likely be much anyway. For the most part and speaking in generality, a head with more than a 5cc advantage will likely have a greater minimum cross sectional area, and a head with more than 10 cc's of an advantage will VERY likely have a larger minimum cross section (probably 99% of the time).
Our 225 head usually cc's in the high 220's....looking over the list of heads in that cross section, that type of intake volume represents less than the average in the group (on the small side) yet even out of the box they flow even with, or better than, most of the larger (and much larger) cylinder heads in my database. That can only happen with a well shaped efficient port (and chamber) design which promotes high airspeed inertia aiding in good cylinder fill, less reversion issues, and a host of other positive side benefits.
By the way I mentioned ET purely because they have the most rolled over cathedral port opening at 11' and I have seen a handful of their product (which is very impressive) next to our own.
Hope this info helps...
Tony
The fact a certain head has a valve angle of 11' or 13.5 degrees means nothing....its where you position the valve in the chamber (fore and aft) that will make a larger difference and once again its nominal in most cases anyway. Why quote volume? Because volume is the quickest and easiest way to compare runner size and cross sectional area. You need a scanned digitized surface to accurately quote minimum cross sectional area and that's not going to happen unless you digitize every head that crosses our flowbench. Sure....within a 5cc difference a comparison of minimum cross sectional area might go one way or the other (the larger volume head could have a smaller minimum cross section) but the difference once again wouldn't likely be much anyway. For the most part and speaking in generality, a head with more than a 5cc advantage will likely have a greater minimum cross sectional area, and a head with more than 10 cc's of an advantage will VERY likely have a larger minimum cross section (probably 99% of the time).
Our 225 head usually cc's in the high 220's....looking over the list of heads in that cross section, that type of intake volume represents less than the average in the group (on the small side) yet even out of the box they flow even with, or better than, most of the larger (and much larger) cylinder heads in my database. That can only happen with a well shaped efficient port (and chamber) design which promotes high airspeed inertia aiding in good cylinder fill, less reversion issues, and a host of other positive side benefits.
By the way I mentioned ET purely because they have the most rolled over cathedral port opening at 11' and I have seen a handful of their product (which is very impressive) next to our own.
Hope this info helps...
Tony
08-31-2007, 01:18 PM
#247
Originally Posted by LS1curious
Reading this sort of makes me wonder how it is exactly that you measure port cross section?. I have alway looked at port cross section from the viewpoint as well as most others as the opening of the primary portion of the runner itself. the bowl area sort of has to be large. With the shape change the runner undertakes there if you didn't make the bowl area large enough it would flat out kill the short side turn.
Can you post upthe runner opening sizes ? easy enough to measure and most port usually only expand from that point forward if not tapper down but its a fiarly consistent measure of cross section.
Can you post upthe runner opening sizes ? easy enough to measure and most port usually only expand from that point forward if not tapper down but its a fiarly consistent measure of cross section.
Perhaps this is a topic you may feel worthy of its own thread? Trying to keep things on track here. Feel free to PM or call me at AFR if you would like further clarification of some of what I touched on.
(661)257-8124 Ext. 109
Tony
Last edited by Tony Mamo @ AFR; 08-31-2007 at 01:25 PM.
08-31-2007, 02:18 PM
#248
Tony,
Thanks for helping Shiz out. Me and him have learned ALOT from each others cars over the last few years and my troubles are one of the reasons he has AFR's on the car. I will say it was one of the best things we have done to his car to date.
Who else makes out of the box 8 second heads
Steve got his short block in today, with the long weekend we should have it in and running soon. Look for some dyno numbers next weekend.
Thanks again Tony !
Thanks for helping Shiz out. Me and him have learned ALOT from each others cars over the last few years and my troubles are one of the reasons he has AFR's on the car. I will say it was one of the best things we have done to his car to date.
Who else makes out of the box 8 second heads
Steve got his short block in today, with the long weekend we should have it in and running soon. Look for some dyno numbers next weekend.
Thanks again Tony !
08-31-2007, 04:06 PM
#249
TECH Enthusiast
Join Date: May 2007
Posts: 538
Likes: 0
Received 0 Likes
on
0 Posts
Well a roof to floor measurement may be a bit decieving in and off itself. I know for a fact however the some of the rolled valve angle heads with there relocated valve geometry do in fact have ports that are long enough to make up at least 5-10 cc's.
Maybe if you want to start a thread on port shape and cros section that would be a great topic of discussion.
Maybe if you want to start a thread on port shape and cros section that would be a great topic of discussion.
Originally Posted by Tony Mamo @ AFR
The port opening and/or entrance into the port never represents the MCSA (minimum cross sectional area)....not on these engines at least or anything Gen III/IV SBC related we may be discussing. In fact the cathedral port opening is larger than it even needs to be but thats another discussion entirely. The smallest area is usually in the port approaching the short turn or directly over the short turn itself between the floor of the turn and the roof of the bowl. Take a closer look at an AFR 205 cc runner next time and how tall the short turn is (.500 taller than stock!)....the tightest point in that port is right there at the crest of the short turn speeding up the air just before it discharges from the port/valvejob.
Perhaps this is a topic you may feel worthy of its own thread? Trying to keep things on track here. Feel free to PM or call me at AFR if you would like further clarification of some of what I touched on.
(661)257-8124 Ext. 109
Tony
Perhaps this is a topic you may feel worthy of its own thread? Trying to keep things on track here. Feel free to PM or call me at AFR if you would like further clarification of some of what I touched on.
(661)257-8124 Ext. 109
Tony
08-31-2007, 04:47 PM
#250
Originally Posted by LS1curious
Well a roof to floor measurement may be a bit decieving in and off itself. I know for a fact however the some of the rolled valve angle heads with there relocated valve geometry do in fact have ports that are long enough to make up at least 5-10 cc's.
Maybe if you want to start a thread on port shape and cros section that would be a great topic of discussion.
Maybe if you want to start a thread on port shape and cros section that would be a great topic of discussion.
The advanced tech section would be the most appropriate place to start it, but I'm not sure if it gets enough views to get the word out. This section gets the most views. I'll let you decide where you'd like to start it.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX tuning in person or via email press here.
08-31-2007, 06:40 PM
#251
TECH Enthusiast
Join Date: May 2007
Posts: 538
Likes: 0
Received 0 Likes
on
0 Posts
Ahhh I am tired of starting conversations. I don't really have a whole lot to add. This is a topic for manufacturers to prove there metal.Maybe we could all learn something. It would be interesting however to have some of the manufacutrer info or porter info in this thread. If somebody gets there feelings hurt ??? work on the product.
If i had a list of the various heads tested here I could try to arrange to have them flowed by a third party totally uninvolved in the LS1 market. this would put the total fairness questions to bed.
If i had a list of the various heads tested here I could try to arrange to have them flowed by a third party totally uninvolved in the LS1 market. this would put the total fairness questions to bed.
Originally Posted by Patrick G
Sean, you have lots of experience in this area. I bet if you started the thread, you'd get plenty of people like Tony Mamo, Brian Tooley, Greg Goode, Carey from ET, and others to chime in. Better for a shop to start the thread rather than a manufacturer.
The advanced tech section would be the most appropriate place to start it, but I'm not sure if it gets enough views to get the word out. This section gets the most views. I'll let you decide where you'd like to start it.
The advanced tech section would be the most appropriate place to start it, but I'm not sure if it gets enough views to get the word out. This section gets the most views. I'll let you decide where you'd like to start it.
09-10-2007, 06:57 PM
#254
Originally Posted by ty_ty13
can i ask who ported the afr 225's?
(BTW im the one who you just talked to)
(BTW im the one who you just talked to)
Anyway, I did all the work personally....most of it more aimed at optimizing and increasing their efficiency, not removing alot of material. Shiznity's heads (the last 225 on the last) I did spend a little more time enlarging the exhaust port clearly knowing its intended application but even that work was somewhat conservative. It may have been a cc larger than the other ported 225 a few posts above.
Hope this helps...
"As the LS1 turns" to be continued....LOL
Regards,
Tony
09-25-2007, 12:53 PM
#256
Staging Lane
Join Date: Aug 2006
Location: Suffolk, NY
Posts: 51
Likes: 0
Received 0 Likes
on
0 Posts
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 everyones 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 .Volume Comm ents .
A .136 .199 .257 .294 .305 .313 232 ccs
B .134 .195 .239 .267 .280 .289 229 ccs
C .131 .189 .240 .275 .287 .282 221 ccs (LS1 castings)
D .141 .206 .259 .291 .303 .313 231 ccs
E .145 .203 .253 .295 .309 .321 246 ccs .Stg 3
F .141 .206 .263 .300 .315 .332 245 ccc .Stg 3
G .135 .201 .260 .304 .316 .T 239 ccs Stg 3
H .140 .211 .260 .285 .286 .287 243 ccs Weak for size
I ..137 .207 .252 .290 .306 .318 242 ccs Stg 3
J. .126 .186 .231 .263 .277 .290 228 ccs
K .121 .190 .246 .278 .293 .306 230 ccs
L .146 .208 .264 .301 .314 .323 237 ccs.Stg.3 (good overall)
M 137 .207 .252 .290 .306 .318 242 ccs Stg 3
N .136 .190 .249 .288 .301 .312 241 ccs Stg. 3
"O"...147....213...264...300....308...304..... .249 cc's.....Stg. 3
"P"....144...205...259....299....316...330......24 9 cc's....Stg. 3
"Q"....129...200...258...295....305...308..... .232 cc's
"R"....135...200...251....293....311...317......25 4 cc's....Stg3 (BIG!)
"S"....148...200...247....289....301...304......23 1 cc's...LS6 head w/ 2.02
"T"....132...195...240....283....296... "T"......227 cc's...LS1 head w/ 2.02
"U"....136...194...248....267....275...281......23 4 cc's....5.3 head/weak #'s
"V"....128...186...238....274....287...293......23 1 cc's
"W"...141...206...256....299....315...324..... .236 cc's ...LS6 Casting/Good#'s
"X"....143...207...265....298....313...."T'......2 40 cc's....Ported 6.0 Casting
"Y"....136...197...242....281....294....293.....23 0 cc's...Stg 3 (soft #'s)
"Z"....137...211...270....310....324....336.....240 cc's ..New "Best" peak #'s
"a"....138...205...259....295....304....309.....25 4 cc's ..CNC Ported Dart/BIG
"b"....160...240...305....342....N/A....368.....275 cc's ..."b" for BAD AZZZZ!
"c"....141...214...267....303....306....311.....21 5 cc's....Very good #'s (11')
"d"....138...215...264....304....317...."T"......2 29 cc's....Rolled Valve (13.5')
"e"....158...228...279....315....324....331.....230 cc's....Huge area under curve
"f"....161...225...272....312....321....323.....240 cc's....Very solid #'s!
"g"...159...228...281....314....324....330.....230 cc's....Ported AFR 225's
AVG..137 .200 .252 ..289 .302 .308.... 237 ccs
AirFlow Research #s
205 .145 .210 .257 .290 .301 .308 205 ccs...(205 w/ 4.125 #s)
225 .151 .221 .270 .306 .315 .322 229 ccs
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 ccs
B .107 .147 .196 .218 .228 .85 ccs
C .107 .153 .184 .205 .217 .82 ccs
D .112 .165 .195 .215 .228 .86 ccs
E .111 .156 .202 .235 .246 ... 88 ccs
F .126 .170 .204 .226 .236 .85 ccs
G 117 .164 .201 .229 .242 87 ccs
H 113 .156 .189 .221 .231 85 ccs
I .114 .145 .179 .211 .237 87 ccs
J ..97 .133 .166 .193 .213 89 ccs Very weak for size
K .117 157 .194 .218 .228 83 ccs
L .114 .155 .214 .238 .252 ..90 ccs Big, but good #s
M 120 .177 .219 .240 .251 ..87 ccs .....good #s
N .105 .144 .177 .208 .222 ..89 ccs Very weak for size
"O"....115...166...202...228...241............ .88 cc's
"P"....116...163....211...236...241........... .84 cc's
"Q"....109...156....208...224...227........... .89 cc's.....Weak for it's size
"R"....113....156...195...227...241........... .91 cc's......(BIG!)
"S"....108....146...188...226...235........... .84 cc's....Soft low/midlift #'s
"T"....120....171...200...217...224........... .84 cc's...1.570 vlv, good low#'s
"U"....111....147...189...209...224........... .84 cc's
"V"....111....144...168...186...194........... .86 cc's....VERY weak Exh #'s
"W"...126....177...215...230...241............ 82 cc's.....Good #'s
"X"....115....150...177...194...208........... .89 cc's....Very weak for size
"Y"....119....160...182...195...200............83. 5 cc's..Small port/Very soft #s
"Z"....117....170...215...241...253........... .95 cc's.....BIG port / strong #'s
"a"....114....153...193...220...233........... .90 cc's.....BIG port / avg. #'s
"b"....120....176...205...221...230........... .86 cc's.....Needs MORE!
"c"....118....164...207...232...245........... .96 cc's.....Good numbers / BIG
"d"....110....174...213...231...240........... .84 cc's.....Good #'s
"e"....128....184...228...245...253............85 cc's.....Big numbers everywhere
"f".....124....164...203...226...235.......... ..84 cc's
"g"....131....179..230...249...255............85 cc's.....Ported AFR 225's
AVG...113 .157 .194 .219 .230 .86 ccs
AirFlow Research #s
205 .118 .171 .206 .226 .240 ..84 ccs
225 .120 .180 .220 .241 .250 ..85 ccs
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 everyones 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 .Volume Comm ents .
A .136 .199 .257 .294 .305 .313 232 ccs
B .134 .195 .239 .267 .280 .289 229 ccs
C .131 .189 .240 .275 .287 .282 221 ccs (LS1 castings)
D .141 .206 .259 .291 .303 .313 231 ccs
E .145 .203 .253 .295 .309 .321 246 ccs .Stg 3
F .141 .206 .263 .300 .315 .332 245 ccc .Stg 3
G .135 .201 .260 .304 .316 .T 239 ccs Stg 3
H .140 .211 .260 .285 .286 .287 243 ccs Weak for size
I ..137 .207 .252 .290 .306 .318 242 ccs Stg 3
J. .126 .186 .231 .263 .277 .290 228 ccs
K .121 .190 .246 .278 .293 .306 230 ccs
L .146 .208 .264 .301 .314 .323 237 ccs.Stg.3 (good overall)
M 137 .207 .252 .290 .306 .318 242 ccs Stg 3
N .136 .190 .249 .288 .301 .312 241 ccs Stg. 3
"O"...147....213...264...300....308...304..... .249 cc's.....Stg. 3
"P"....144...205...259....299....316...330......24 9 cc's....Stg. 3
"Q"....129...200...258...295....305...308..... .232 cc's
"R"....135...200...251....293....311...317......25 4 cc's....Stg3 (BIG!)
"S"....148...200...247....289....301...304......23 1 cc's...LS6 head w/ 2.02
"T"....132...195...240....283....296... "T"......227 cc's...LS1 head w/ 2.02
"U"....136...194...248....267....275...281......23 4 cc's....5.3 head/weak #'s
"V"....128...186...238....274....287...293......23 1 cc's
"W"...141...206...256....299....315...324..... .236 cc's ...LS6 Casting/Good#'s
"X"....143...207...265....298....313...."T'......2 40 cc's....Ported 6.0 Casting
"Y"....136...197...242....281....294....293.....23 0 cc's...Stg 3 (soft #'s)
"Z"....137...211...270....310....324....336.....240 cc's ..New "Best" peak #'s
"a"....138...205...259....295....304....309.....25 4 cc's ..CNC Ported Dart/BIG
"b"....160...240...305....342....N/A....368.....275 cc's ..."b" for BAD AZZZZ!
"c"....141...214...267....303....306....311.....21 5 cc's....Very good #'s (11')
"d"....138...215...264....304....317...."T"......2 29 cc's....Rolled Valve (13.5')
"e"....158...228...279....315....324....331.....230 cc's....Huge area under curve
"f"....161...225...272....312....321....323.....240 cc's....Very solid #'s!
"g"...159...228...281....314....324....330.....230 cc's....Ported AFR 225's
AVG..137 .200 .252 ..289 .302 .308.... 237 ccs
AirFlow Research #s
205 .145 .210 .257 .290 .301 .308 205 ccs...(205 w/ 4.125 #s)
225 .151 .221 .270 .306 .315 .322 229 ccs
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 ccs
B .107 .147 .196 .218 .228 .85 ccs
C .107 .153 .184 .205 .217 .82 ccs
D .112 .165 .195 .215 .228 .86 ccs
E .111 .156 .202 .235 .246 ... 88 ccs
F .126 .170 .204 .226 .236 .85 ccs
G 117 .164 .201 .229 .242 87 ccs
H 113 .156 .189 .221 .231 85 ccs
I .114 .145 .179 .211 .237 87 ccs
J ..97 .133 .166 .193 .213 89 ccs Very weak for size
K .117 157 .194 .218 .228 83 ccs
L .114 .155 .214 .238 .252 ..90 ccs Big, but good #s
M 120 .177 .219 .240 .251 ..87 ccs .....good #s
N .105 .144 .177 .208 .222 ..89 ccs Very weak for size
"O"....115...166...202...228...241............ .88 cc's
"P"....116...163....211...236...241........... .84 cc's
"Q"....109...156....208...224...227........... .89 cc's.....Weak for it's size
"R"....113....156...195...227...241........... .91 cc's......(BIG!)
"S"....108....146...188...226...235........... .84 cc's....Soft low/midlift #'s
"T"....120....171...200...217...224........... .84 cc's...1.570 vlv, good low#'s
"U"....111....147...189...209...224........... .84 cc's
"V"....111....144...168...186...194........... .86 cc's....VERY weak Exh #'s
"W"...126....177...215...230...241............ 82 cc's.....Good #'s
"X"....115....150...177...194...208........... .89 cc's....Very weak for size
"Y"....119....160...182...195...200............83. 5 cc's..Small port/Very soft #s
"Z"....117....170...215...241...253........... .95 cc's.....BIG port / strong #'s
"a"....114....153...193...220...233........... .90 cc's.....BIG port / avg. #'s
"b"....120....176...205...221...230........... .86 cc's.....Needs MORE!
"c"....118....164...207...232...245........... .96 cc's.....Good numbers / BIG
"d"....110....174...213...231...240........... .84 cc's.....Good #'s
"e"....128....184...228...245...253............85 cc's.....Big numbers everywhere
"f".....124....164...203...226...235.......... ..84 cc's
"g"....131....179..230...249...255............85 cc's.....Ported AFR 225's
AVG...113 .157 .194 .219 .230 .86 ccs
AirFlow Research #s
205 .118 .171 .206 .226 .240 ..84 ccs
225 .120 .180 .220 .241 .250 ..85 ccs
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
I like graphics...
Does anyone have bench flows for the stock LS6 heads?
11-19-2007, 01:32 PM
#258
The soap opera continues! Just had the opportunity to look over and flowtest what was described as a killer set of hand ported AFR's....specifically designed for a solid roller engine (small letter "h" at the bottom of my flowthread on page one).
These cylinder heads actually started life as our own 205 CNC castings and word has it were extensively hand ported by a well known and respected LSx head porter (don't ask). I will let you guys be the judge of the results. I would like to add that the chamber, port design, and runner volume on the intake side was very condusive to high lift flow but it took till .650 lift (328 CFM) to finally clear the much smaller AFR 225 right out of the box. However, the downside of the "high lift" design approach was weak low and midlift figures. An AFR 225 is 10-20 CFM stronger from the crack of the valve to .400 lift with much higher airspeed to boot.....it would take a huge cam and an enormous amount of peak flow gains to make up the airflow lost in the bottom of the curve.
While this big runner actually did pull a clean .700 number (336 CFM), that represents purely a bragging right number than anything else. Its simply not usable for 99.5 % of the people reading this, not to mention would have been too little too late to make up for weaker low/midlift numbers.
The exhaust port was weak....no way to sugar coat it. It was obvious looking at these castings that the bulk of the time was spent on the intake side (there was epoxy on all of the intake port floors and short turns). To be honest, the out of the box 205 CNC exh. port would have been far more efficient and about 10 CFM stronger had it been left alone as delivered from us. I was short on time and didnt have a chance to pour it, but my best guess was a port a few cc's larger than a stock 205 (perhaps it was 86 cc's or so). I suspect the valvejob hurt it more than the actual port shape.
In a few months we will be releasing the AFR 235 and that will be an interesting comparo against this head. The way its shaping up it looks to match this big heads's .700 number by .600, and clear it by another 5 CFM or so at .650, inspite of the fact it will be almost 15 cc's smaller. Note the big numbers come at a far more user friendly lift point and there will be no penalty of low and midlift flow with our new design either. The exhaust port will also be impressive, clearing every head on the flowthread (including a few of my handworked 225 ports) with a legit 255-260 CFM @ .600 lift and huge low and mids to compliment that figure. Its shaping up to be the best overall large port cathedral head I have had the opportunity to test regardless of valve angle or size.
Im putting the last few finishing touches on the prototype design as we speak (hoping to eek out a few more precious CFM!) and with a little luck should have it in the Engineering Dept's hands in a few weeks if things go well (and I dont get to sidetracked with other responsibilities which inevidably always happens). My best guess is availability in early 08'....I will keep you guys posted.
Cheers,
Tony
BTW....This new head design is aimed at the larger displacement crowd....a 4" or larger bore minimum and preferably a 4" or larger stroke. You could consider it on an aggressive very high strung 6.0, especially with a solid roller. It will also work extremely well on aggressive 400+ CID blown applications as well, however if you primarily drive it on the street, the smaller 225 would still be your best bet.
These cylinder heads actually started life as our own 205 CNC castings and word has it were extensively hand ported by a well known and respected LSx head porter (don't ask). I will let you guys be the judge of the results. I would like to add that the chamber, port design, and runner volume on the intake side was very condusive to high lift flow but it took till .650 lift (328 CFM) to finally clear the much smaller AFR 225 right out of the box. However, the downside of the "high lift" design approach was weak low and midlift figures. An AFR 225 is 10-20 CFM stronger from the crack of the valve to .400 lift with much higher airspeed to boot.....it would take a huge cam and an enormous amount of peak flow gains to make up the airflow lost in the bottom of the curve.
While this big runner actually did pull a clean .700 number (336 CFM), that represents purely a bragging right number than anything else. Its simply not usable for 99.5 % of the people reading this, not to mention would have been too little too late to make up for weaker low/midlift numbers.
The exhaust port was weak....no way to sugar coat it. It was obvious looking at these castings that the bulk of the time was spent on the intake side (there was epoxy on all of the intake port floors and short turns). To be honest, the out of the box 205 CNC exh. port would have been far more efficient and about 10 CFM stronger had it been left alone as delivered from us. I was short on time and didnt have a chance to pour it, but my best guess was a port a few cc's larger than a stock 205 (perhaps it was 86 cc's or so). I suspect the valvejob hurt it more than the actual port shape.
In a few months we will be releasing the AFR 235 and that will be an interesting comparo against this head. The way its shaping up it looks to match this big heads's .700 number by .600, and clear it by another 5 CFM or so at .650, inspite of the fact it will be almost 15 cc's smaller. Note the big numbers come at a far more user friendly lift point and there will be no penalty of low and midlift flow with our new design either. The exhaust port will also be impressive, clearing every head on the flowthread (including a few of my handworked 225 ports) with a legit 255-260 CFM @ .600 lift and huge low and mids to compliment that figure. Its shaping up to be the best overall large port cathedral head I have had the opportunity to test regardless of valve angle or size.
Im putting the last few finishing touches on the prototype design as we speak (hoping to eek out a few more precious CFM!) and with a little luck should have it in the Engineering Dept's hands in a few weeks if things go well (and I dont get to sidetracked with other responsibilities which inevidably always happens). My best guess is availability in early 08'....I will keep you guys posted.
Cheers,
Tony
BTW....This new head design is aimed at the larger displacement crowd....a 4" or larger bore minimum and preferably a 4" or larger stroke. You could consider it on an aggressive very high strung 6.0, especially with a solid roller. It will also work extremely well on aggressive 400+ CID blown applications as well, however if you primarily drive it on the street, the smaller 225 would still be your best bet.
Last edited by Tony Mamo @ AFR; 11-19-2007 at 02:18 PM.
01-19-2009, 12:13 PM
#260
Quite an excellent thread. Why not a sticky?
Through a MAF, have recorded 438 g/s max airflow. MAF table has been calibrated & PCM tuned for all current mods. Assuming (I know....that word is gonna get me into trouble) that 2.45 cylinders are filling simultaneously, this resulted in a calculated 294 CFM per runner. Only thing I'm not sure of is exactly how many cylinders are filling. For sure there are two & then figured the .45 being related to others beginning to pull air.
Do these numbers seem reasonable? How many cylinders are actually pulling air @ one time? Seems like the 2.45 is a close estimate. Thank-you for any input.
(438 x 60) / 36.53 = 720 CFM...............720/2.45 = 294 CFM per runner.
Through a MAF, have recorded 438 g/s max airflow. MAF table has been calibrated & PCM tuned for all current mods. Assuming (I know....that word is gonna get me into trouble) that 2.45 cylinders are filling simultaneously, this resulted in a calculated 294 CFM per runner. Only thing I'm not sure of is exactly how many cylinders are filling. For sure there are two & then figured the .45 being related to others beginning to pull air.
Do these numbers seem reasonable? How many cylinders are actually pulling air @ one time? Seems like the 2.45 is a close estimate. Thank-you for any input.
(438 x 60) / 36.53 = 720 CFM...............720/2.45 = 294 CFM per runner.