The "AFR 225" Thread
10-27-2004 | 05:11 AM
#21
Originally Posted by Tony Mamo @ AFR
Hey Guys...
For our next "AFR installment"…..How about we talk about FLOW NUMBERS??
Sounds like a plan and I know it’s the “meat and potatoes” you have all been waiting to see. First off, if your even thinking about comparing flow numbers from one source to another….don’t bother. At best it might be close…..at worst you might be 40 CFM away, and the reality is that in most cases, the actual results if compared on the same bench will be somewhere in the middle. Too many variables, and I know this has been hashed to death in the past, but to name a few….What make or type of flow bench?...When was it calibrated last?....What size bore fixture?.....Does it leak any air?....What type of a radiused inlet was used (clay or otherwise)…..How was the head positioned on the fixture?......Was a pipe used on the exhaust?......Was it actually shaped like most production headers (curving almost immediately exiting the port)?......Who operated the equipment and how was the data recorded? Etc…Etc….Etc. Not to mention are the flow numbers “advertised” that you are comparing actual production numbers or are they the best numbers recorded off the best port of a prototype head the was copied and your actual results might “vary”. Bottom line, even the AFR 205 at an actual 298-301 CFM’s (about the average from many production pieces tested) has outflowed 85-90 % of factory ported castings that I have seen from all over this country (and accomplished this with a considerably smaller intake port). AFR has been obtaining, borrowing, and in some cases BUYING, products from our competitors as part of the exhaustive R&D effort just to see how we truly stack up against as much of the competition we could get our hands on….not to mention we will continue to do so in the future. Don’t ask for names because I WON”T even go there….Have I flowtested every product every manufacturer offers?….of course not. But the products I have had the opportunity to evaluate have been quite a bit off of their advertised #’s….at least on our testing equipment….some of them off as much as 40 CFM!! (that would ruin your day after laying out you hard earned dollars).
With that said, let me cut to the chase….Our goals with the 225 head was to stay true to our beliefs that big power is not made with huge ports and “sexy” big peak flow numbers….big power is made with a cylinder head that has a moderately sized cross section (and runner volume) and moves a lot of air…everywhere…at high airspeeds for better cylinder filling….especially all thru the low and mid-lifts where the valve actually spends MUCH more time than close to a peak number on a cam card. You know how much time in crank degrees a .610 lift cam actually spends over .600 lift….probably NONE. At higher RPM’s , deflection in valvetrain parts coupled with hydraulic lifters slightly compressing under load would probably knock .010 -.020 lift right off the top. BUT….do you know how many crank degrees are spent between .500 and .550 with the same cam ….if its an XER lobe, probably 60-80….not to mention all the time spent on the way to those lifts as well as all the time spent on the way back down from those lifts.
During the “design phase” of the 225, I made several conscious decisions in shaping the port, shaping the valve job etc., that HURT peak flow because I saw a significant increase in flow from .200-.500 lift. I felt it was a “good trade” that would actually enhance power output, although I can’t lie….it always killed me knowing I was losing some “bragging” rights in our catalog and website.
On to the numbers….This information was recorded utilizing an SF600 Superflow with a 4.125 bore, radiused inlet, “hooked” 1.875 exhaust tube (about 10 inches in total length, and represents an “average” of many of the 72 cc 225 heads tested as we “dialed” in the program over the last few weeks. Advertised numbers you will soon see in our catalog and website might vary slightly by a CFM or two.
Intake Flow @ 28”
.200 152 CFM
.300 221 CFM
.400 268 CFM
.500 306 CFM
.550 315 CFM
.600 322 CFM
Exhaust Flow @ 28” w/ a 1.875 Flow Tube
.200 122 CFM
.300 180 CFM
.400 220 CFM
.500 241 CFM
.600 250 CFM
By the way, the exhaust numbers are crushing everywhere and reflect some of the best numbers I have personally witnessed from a small block “production” style cylinder head (versus what I would call more “exotic” like a raised runner 12 or 14 degree head).
I know some of you have asked some questions which I will address tomorrow as soon as I find some time….This post is already way too long but hopefully you hung with it and maybe picked up on some things you haven’t considered in the past.
Regards,
Tony Mamo
For our next "AFR installment"…..How about we talk about FLOW NUMBERS??
Sounds like a plan and I know it’s the “meat and potatoes” you have all been waiting to see. First off, if your even thinking about comparing flow numbers from one source to another….don’t bother. At best it might be close…..at worst you might be 40 CFM away, and the reality is that in most cases, the actual results if compared on the same bench will be somewhere in the middle. Too many variables, and I know this has been hashed to death in the past, but to name a few….What make or type of flow bench?...When was it calibrated last?....What size bore fixture?.....Does it leak any air?....What type of a radiused inlet was used (clay or otherwise)…..How was the head positioned on the fixture?......Was a pipe used on the exhaust?......Was it actually shaped like most production headers (curving almost immediately exiting the port)?......Who operated the equipment and how was the data recorded? Etc…Etc….Etc. Not to mention are the flow numbers “advertised” that you are comparing actual production numbers or are they the best numbers recorded off the best port of a prototype head the was copied and your actual results might “vary”. Bottom line, even the AFR 205 at an actual 298-301 CFM’s (about the average from many production pieces tested) has outflowed 85-90 % of factory ported castings that I have seen from all over this country (and accomplished this with a considerably smaller intake port). AFR has been obtaining, borrowing, and in some cases BUYING, products from our competitors as part of the exhaustive R&D effort just to see how we truly stack up against as much of the competition we could get our hands on….not to mention we will continue to do so in the future. Don’t ask for names because I WON”T even go there….Have I flowtested every product every manufacturer offers?….of course not. But the products I have had the opportunity to evaluate have been quite a bit off of their advertised #’s….at least on our testing equipment….some of them off as much as 40 CFM!! (that would ruin your day after laying out you hard earned dollars).
With that said, let me cut to the chase….Our goals with the 225 head was to stay true to our beliefs that big power is not made with huge ports and “sexy” big peak flow numbers….big power is made with a cylinder head that has a moderately sized cross section (and runner volume) and moves a lot of air…everywhere…at high airspeeds for better cylinder filling….especially all thru the low and mid-lifts where the valve actually spends MUCH more time than close to a peak number on a cam card. You know how much time in crank degrees a .610 lift cam actually spends over .600 lift….probably NONE. At higher RPM’s , deflection in valvetrain parts coupled with hydraulic lifters slightly compressing under load would probably knock .010 -.020 lift right off the top. BUT….do you know how many crank degrees are spent between .500 and .550 with the same cam ….if its an XER lobe, probably 60-80….not to mention all the time spent on the way to those lifts as well as all the time spent on the way back down from those lifts.
During the “design phase” of the 225, I made several conscious decisions in shaping the port, shaping the valve job etc., that HURT peak flow because I saw a significant increase in flow from .200-.500 lift. I felt it was a “good trade” that would actually enhance power output, although I can’t lie….it always killed me knowing I was losing some “bragging” rights in our catalog and website.
On to the numbers….This information was recorded utilizing an SF600 Superflow with a 4.125 bore, radiused inlet, “hooked” 1.875 exhaust tube (about 10 inches in total length, and represents an “average” of many of the 72 cc 225 heads tested as we “dialed” in the program over the last few weeks. Advertised numbers you will soon see in our catalog and website might vary slightly by a CFM or two.
Intake Flow @ 28”
.200 152 CFM
.300 221 CFM
.400 268 CFM
.500 306 CFM
.550 315 CFM
.600 322 CFM
Exhaust Flow @ 28” w/ a 1.875 Flow Tube
.200 122 CFM
.300 180 CFM
.400 220 CFM
.500 241 CFM
.600 250 CFM
By the way, the exhaust numbers are crushing everywhere and reflect some of the best numbers I have personally witnessed from a small block “production” style cylinder head (versus what I would call more “exotic” like a raised runner 12 or 14 degree head).
I know some of you have asked some questions which I will address tomorrow as soon as I find some time….This post is already way too long but hopefully you hung with it and maybe picked up on some things you haven’t considered in the past.
Regards,
Tony Mamo
10-27-2004 | 06:32 AM
#23
TECH Apprentice
Joined: Jan 2004
Posts: 305
Likes: 0
Ok..My 02 cents and a comment/question..
I have also found great disparity in head flow #'s from advertised to the actual. Testing I had done on most of the venders heads in here certainly show they typically flow 30 or so CFM less than advertised. And yes, All the testing was done the same way from head to head, radiused inlet,SF600 calibrated,Same shop and operater, blah blah..
But, Here is the interesting things, We tested 4 different style AFR heads (Ford and GM) and all flowed within +/- 3 CFM of advertised. Only AFR and Trick Flow (Ford heads) flow as claimed, Period. Now keep in mind..We paid $75 bucks a head to find this out, and it was the best investment we made in the long run.
Now, for the real question to Tony..FLow #s on a 3.90 or even a 4.0" bore. Something a bit more representitve of the normal user.
Dave
I have also found great disparity in head flow #'s from advertised to the actual. Testing I had done on most of the venders heads in here certainly show they typically flow 30 or so CFM less than advertised. And yes, All the testing was done the same way from head to head, radiused inlet,SF600 calibrated,Same shop and operater, blah blah..
But, Here is the interesting things, We tested 4 different style AFR heads (Ford and GM) and all flowed within +/- 3 CFM of advertised. Only AFR and Trick Flow (Ford heads) flow as claimed, Period. Now keep in mind..We paid $75 bucks a head to find this out, and it was the best investment we made in the long run.
Now, for the real question to Tony..FLow #s on a 3.90 or even a 4.0" bore. Something a bit more representitve of the normal user.
Dave
10-27-2004 | 11:43 AM
#26
Small Bore Flow #'s... OK....
Quick update...
Here is the same 225 head I quoted flow numbers on earlier, but flow tested on the stock 3.900 bore. Notice how even with the additional "shrouding" of the larger 2.08 intake valve, the correct shapes and contours of the new 225 still provide very impressive gains right from "jumpstreet". Bottom line, I started my R&D on this project with the smaller 2.055 valve but when the smoke cleared, I found a way to utilize the larger 2.080 with better results at every lift point even with the stock 3.900 bore.
Also, I pulled a 205 out of production to compare at the exact same time I flowed the 225 this morning...note how close to "advertised" the 205 actually flows, and how the larger 225 has significantly more "area under the curve" starting immediatly.
Intake @ 28" (3.900 Bore size)
205 225
.200 142 CFM 151 CFM +9
.300 202 CFM 210 CFM +10
.400 246 CFM 258 CFM +12
.500 280 CFM 292 CFM +12
.550 292 CFM 305 CFM +13
.600 300 CFM 314 CFM +14
Guys, as far as the exhaust number go, I ALWAYS flow test every "small block" cylinder head (Ford, Chevy, Mopar....whatever) with the SAME 1.875 flow pipe....I have used this same pipe for 8 years or so....this way when I look at all my documentation so I can personally compare one head to another (even if i flowtested it 6 years ago) I don't have any variables to consider. However, I will obtain a 1.75 pipe to quote you guys the information you request, but once again, all of the "factory ported" castings I have flowtest all had the same 1.875 pipe on it and trust me when I tell you that I haven't seen anything else come close....especially in the low and midlift #'s.
I might not be able to provide you with that info till I get back from SEMA, but I will post it as soon as I have completed the testing.
Thanks,
Tony
Quick update...
Here is the same 225 head I quoted flow numbers on earlier, but flow tested on the stock 3.900 bore. Notice how even with the additional "shrouding" of the larger 2.08 intake valve, the correct shapes and contours of the new 225 still provide very impressive gains right from "jumpstreet". Bottom line, I started my R&D on this project with the smaller 2.055 valve but when the smoke cleared, I found a way to utilize the larger 2.080 with better results at every lift point even with the stock 3.900 bore.
Also, I pulled a 205 out of production to compare at the exact same time I flowed the 225 this morning...note how close to "advertised" the 205 actually flows, and how the larger 225 has significantly more "area under the curve" starting immediatly.
Intake @ 28" (3.900 Bore size)
205 225
.200 142 CFM 151 CFM +9
.300 202 CFM 210 CFM +10
.400 246 CFM 258 CFM +12
.500 280 CFM 292 CFM +12
.550 292 CFM 305 CFM +13
.600 300 CFM 314 CFM +14
Guys, as far as the exhaust number go, I ALWAYS flow test every "small block" cylinder head (Ford, Chevy, Mopar....whatever) with the SAME 1.875 flow pipe....I have used this same pipe for 8 years or so....this way when I look at all my documentation so I can personally compare one head to another (even if i flowtested it 6 years ago) I don't have any variables to consider. However, I will obtain a 1.75 pipe to quote you guys the information you request, but once again, all of the "factory ported" castings I have flowtest all had the same 1.875 pipe on it and trust me when I tell you that I haven't seen anything else come close....especially in the low and midlift #'s.
I might not be able to provide you with that info till I get back from SEMA, but I will post it as soon as I have completed the testing.
Thanks,
Tony
10-27-2004 | 01:13 PM
#27
Tony,
How do you think this combo would work?
346CID forged piston and rod
AFR 225s hand finished 12.0:1 CR
Comp Cams XER 250/258 .6xx .6xx 112LSA Hydro setup
Fast 90mm Intake
Nick Williams 90mm TB
Jesel Adjustable Rockers
Phil
How do you think this combo would work?
346CID forged piston and rod
AFR 225s hand finished 12.0:1 CR
Comp Cams XER 250/258 .6xx .6xx 112LSA Hydro setup
Fast 90mm Intake
Nick Williams 90mm TB
Jesel Adjustable Rockers
Phil
10-27-2004 | 01:47 PM
#29
Originally Posted by Phil99vette
Tony,
How do you think this combo would work?
346CID forged piston and rod
AFR 225s hand finished 12.0:1 CR
Comp Cams XER 250/258 .6xx .6xx 112LSA Hydro setup
Fast 90mm Intake
Nick Williams 90mm TB
Jesel Adjustable Rockers
Phil
How do you think this combo would work?
346CID forged piston and rod
AFR 225s hand finished 12.0:1 CR
Comp Cams XER 250/258 .6xx .6xx 112LSA Hydro setup
Fast 90mm Intake
Nick Williams 90mm TB
Jesel Adjustable Rockers
Phil
The combination looks good....I just question whether the Hyd. can effectively get the job done....It would be a "sin" to have to short shift the car to keep the valvetrain out of float.
Regards,
Tony
10-27-2004 | 02:40 PM
#30
TECH Resident
Joined: Sep 2003
Posts: 848
Likes: 1
From: Working in the shop 24/7
Originally Posted by Tony Mamo @ AFR
The combination looks good....I just question whether the Hyd. can effectively get the job done....It would be a "sin" to have to short shift the car to keep the valvetrain out of float.
Regards,
Tony
Regards,
Tony
You know what we can do with those hydraulic rollers..
Dump the XER lobes, use the right ones and it'll run 'til the rods break...
Ed
Last edited by Ed Curtis; 10-27-2004 at 02:49 PM.
10-27-2004 | 03:44 PM
#31
Tony,
How well would the 225 heads perform on your 347 Corvette setup, same compression, 224/228 cam, 3.90 gear, etc.? Compaired to the 205's, would you loose any lowend torgue and driveablity? Would the 225's produce more midrange torque?
How well would the 225 heads perform on your 347 Corvette setup, same compression, 224/228 cam, 3.90 gear, etc.? Compaired to the 205's, would you loose any lowend torgue and driveablity? Would the 225's produce more midrange torque?
10-27-2004 | 04:36 PM
#32
Tony,
Thanks for the flow numbers on the 3.90 bore, that is a good comparison of 205 to 225 they are both awesone numbers.
Any chance of you swapping out the 205 (heads only) on your car and replacing them with the 225 with a 58cc to see a true comparison.
I am on your list and can't hardly wait for the arrival of a set 58cc 225.
Thanks, Bob
Thanks for the flow numbers on the 3.90 bore, that is a good comparison of 205 to 225 they are both awesone numbers.
Any chance of you swapping out the 205 (heads only) on your car and replacing them with the 225 with a 58cc to see a true comparison.
I am on your list and can't hardly wait for the arrival of a set 58cc 225.
Thanks, Bob
10-27-2004 | 06:52 PM
#34
TECH Regular
Joined: Aug 2003
Posts: 414
Likes: 0
From: Berkley, MI
Good stuff !
I'll be at SEMA hunting Mamo down among others. Tony what vehicles @ the show will the 225's be on at SEMA ? It's a big show & I know it's nothing near the DCX booth. I'll talk to the guys w/ the 225's and dutifully report back anything worth mentioning to the crew but showcar builders & booth reps are pretty useless. Tony I'm coming to find you on Wed to talk 205's. And then I'll find out why Edelbrock is flat on their *** again.
I'll be at SEMA hunting Mamo down among others. Tony what vehicles @ the show will the 225's be on at SEMA ? It's a big show & I know it's nothing near the DCX booth. I'll talk to the guys w/ the 225's and dutifully report back anything worth mentioning to the crew but showcar builders & booth reps are pretty useless. Tony I'm coming to find you on Wed to talk 205's. And then I'll find out why Edelbrock is flat on their *** again.
10-27-2004 | 09:58 PM
#35
Tony, I'm curious about your remarks on peak lift/flow numbers. I may be wrong, but from what you posted is seems that it is your belief (you know more than me) that running a cam over .600 or so is a waste because of valvetrain deflection and the little time the cam is a peak lift. I'm setting up my motor for running as fast as I can, top speed. And to get to top speed as quick as possible of course. My cam (hyd) has a peak lift of .635. Would you say this is overkill, and that a head that flows higher at higher lift is unnecessary? I also have a solid cam that has even more lift that I will run in the future. Would the solid be matched best to a head with high peak flow numbers?
10-27-2004 | 10:34 PM
#36
Originally Posted by 11 Bravo
Tony, I'm curious about your remarks on peak lift/flow numbers. I may be wrong, but from what you posted is seems that it is your belief (you know more than me) that running a cam over .600 or so is a waste because of valvetrain deflection and the little time the cam is a peak lift. I'm setting up my motor for running as fast as I can, top speed. And to get to top speed as quick as possible of course. My cam (hyd) has a peak lift of .635. Would you say this is overkill, and that a head that flows higher at higher lift is unnecessary? I also have a solid cam that has even more lift that I will run in the future. Would the solid be matched best to a head with high peak flow numbers?
The point I was making is that while most guys are running cams in the high 500's and low 600's, the reality is that under actual running conditions, the valve won't reach the "peak lift" advertised due to reasons mentioned earlier, and will spend very little time close to "peak lift" as well. The valves will spend considerable time some .100 or so below the peak lift you see advertised on the cam card and it's those numbers and lower that you should be scrutinizing more closely when selecting the proper cylinder heads for your particular application. And more lift is good (assuming you have enough valvespring to maintain valvetrain stability....ie NO valvefloat) because it will get the valve to the higher part of the cylinder head's flowcurve, but even at .630 lift, I would be looking more for how a particular head flows in the .500 - .550 range....That is where your valve will spend quite a bit of time as the lifter "crests" over the peak "arc" of the camlobe both approaching peak lift and going away from peak lift.
Tony M.
10-28-2004 | 05:06 AM
#37
Tony, just ordered a set from Jason. Will be running a 395 Lunati. Seems like 72 chambers would be better for this application, and told Jason a 427 or 441 may be down the road. He said definitely go with the 72's From the flow numbers, at low lift the 225's out flow the 205's. Are you saying that the under the curve numbers will allow the 225 to keep most, if not all the low end torque of the 205, especially with the larger cube motors?
10-29-2004 | 11:45 PM
#40
TECH Addict
Joined: Jan 2002
Posts: 2,950
Likes: 0
From: Magee MS
So these numbers are heads that are fully cnced? if so does that mean that there is not much more room for porting?
I am looking to build a 408 here soon with something like a 244/248 I think the lifs were both around .620 hydraulic roller. I was looking at these heads so I could further port them and get teh flow numbers on up closer to 335 or higher. I was wanting to make a good 500 hp at the rear wheels through an auto.
Josh S.
I am looking to build a 408 here soon with something like a 244/248 I think the lifs were both around .620 hydraulic roller. I was looking at these heads so I could further port them and get teh flow numbers on up closer to 335 or higher. I was wanting to make a good 500 hp at the rear wheels through an auto.
Josh S.