BIG question on AFR's
Flycutting is a must....upgrading parts are optional. Just understand that a better head on the same cubic inch engine will always make more power higher up as it does a better job at filling the cylinders when there is so little time to do so. The long and short of it is to take FULL advantage of the entire power curve a 225 head will provide, shifting in the low 7000's would be about right (more in a big cammed 346 application). Hence the consideration for better rod bolts etc... Keep in mind, you will still make more power till say 7000 RPM's and can shift there if you like (with stock internals), but if you wanted to run your optimal run down the 1320, shifting higher would probably yeild better results because you would have a higher average HP figure during the entire run. Put another way, if you shifted it early at say 6800 or 7000 (which would be just past peak HP), you would be starting further down the power band when you hit your next gear and having to "climb back up"....if you shifted it a say 7300 (assuming good valve control), you would be shifting it as the power curve started cresting over and then you would end up at a higher RPM in the next gear, much closer to the power peak. The goal is to maximixe the power curve and try and "ride the crest" down the entire track. This is much easier to explain with a pen and paper....hope you guys get what I'm trying to explain.
Call me at AFR if you need further clarification...
Tony M.
Call me at AFR if you need further clarification...
Tony M.
Originally Posted by Tony Mamo @ AFR
Flycutting is a must....upgrading parts are optional. Just understand that a better head on the same cubic inch engine will always make more power higher up as it does a better job at filling the cylinders when there is so little time to do so. The long and short of it is to take FULL advantage of the entire power curve a 225 head will provide, shifting in the low 7000's would be about right (more in a big cammed 346 application). Hence the consideration for better rod bolts etc... Keep in mind, you will still make more power till say 7000 RPM's and can shift there if you like (with stock internals), but if you wanted to run your optimal run down the 1320, shifting higher would probably yeild better results because you would have a higher average HP figure during the entire run. Put another way, if you shifted it early at say 6800 or 7000 (which would be just past peak HP), you would be starting further down the power band when you hit your next gear and having to "climb back up"....if you shifted it a say 7300 (assuming good valve control), you would be shifting it as the power curve started cresting over and then you would end up at a higher RPM in the next gear, much closer to the power peak. The goal is to maximixe the power curve and try and "ride the crest" down the entire track. This is much easier to explain with a pen and paper....hope you guys get what I'm trying to explain.
Call me at AFR if you need further clarification...
Tony M.
Call me at AFR if you need further clarification...
Tony M.
....but seriously tony would u suggest an internal upgrade...cause damn thats the last thing i need is when i finally have the money for them(that will be a while) i dont wanna have them slapped on and have somthin inside go wrong that could have been takin care of while the original heads were off.....i ALREADY need to figure out why my car is burning so much oil
Originally Posted by SStheBest
no.....i get what he is sayin but damn shiftin at those rpm's on stock internals??....i better pray i dont miss a gear b/c my pushrods are bound to fly right through the block ....but seriously tony would u suggest an internal upgrade...cause damn thats the last thing i need is when i finally have the money for them(that will be a while) i dont wanna have them slapped on and have somthin inside go wrong that could have been takin care of while the original heads were off.....i ALREADY need to figure out why my car is burning so much oil
....but seriously tony would u suggest an internal upgrade...cause damn thats the last thing i need is when i finally have the money for them(that will be a while) i dont wanna have them slapped on and have somthin inside go wrong that could have been takin care of while the original heads were off.....i ALREADY need to figure out why my car is burning so much oilFor someone NOT wanting to buzz the motor real hard, the 205's and a more aggressive cam might be the better compromise.
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Originally Posted by Tony Mamo @ AFR
Nobody is forcing you to shift at 7000+.....My goal was to convey the nature of the power curve the 225's will typically create. You WILL still make more power with the same combo versus say our own 205's, but the biggest gains between the two curves will be from 6600 and up....
For someone NOT wanting to buzz the motor real hard, the 205's and a more aggressive cam might be the better compromise.
For someone NOT wanting to buzz the motor real hard, the 205's and a more aggressive cam might be the better compromise.
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Joined: Dec 2004
Posts: 576
Likes: 0
From: Chattanooga
Tony, can you post up flow numbers on a 3.9 bore comparring a 205 to 225. That way he can see the flow differences between the 2 cylinder heads. I believe I read that the current 225 was developed for a 4.00" bore and larger?
Originally Posted by SStheBest
so i take it that i have a less chance of screwin somthin up with 205's on stock internals instead of the 225's on stock internals
No you have a less chance at screwing something up if you dont shift above 6800 is what he is trying to say.
Just to give you an example lets say the 205 makes peak power at 6400 and the 225 makes peal power at 6850. Lets also say peak power on the 225 is 450 however at 7000 the power level is still at 443, at 7100 its 440, or 7200 its 438, at 7300 it 429, at 7400 its 415. Why would you want to shift before 7300? To make the car go the fastest you wouldn't. No shifting at those high RPM's adds extra stress on everything, and can make other parts not so happy.
Now lets say the 205's made peak at 6400 and they made 440 peak. At 6500 437, at 6600 435, at 6700 430 at 6800 421 at 6900 412HP. No your starting to fall off of your peak number and should shift between 6700 and 6850, which is a lot less stressful on the motor.
If you dont understand this read it a few times and it will make since.
Originally Posted by JZ'sTA
No you have a less chance at screwing something up if you dont shift above 6800 is what he is trying to say.
Just to give you an example lets say the 205 makes peak power at 6400 and the 225 makes peal power at 6850. Lets also say peak power on the 225 is 450 however at 7000 the power level is still at 443, at 7100 its 440, or 7200 its 438, at 7300 it 429, at 7400 its 415. Why would you want to shift before 7300? To make the car go the fastest you wouldn't. No shifting at those high RPM's adds extra stress on everything, and can make other parts not so happy.
Now lets say the 205's made peak at 6400 and they made 440 peak. At 6500 437, at 6600 435, at 6700 430 at 6800 421 at 6900 412HP. No your starting to fall off of your peak number and should shift between 6700 and 6850, which is a lot less stressful on the motor.
If you dont understand this read it a few times and it will make since.
Just to give you an example lets say the 205 makes peak power at 6400 and the 225 makes peal power at 6850. Lets also say peak power on the 225 is 450 however at 7000 the power level is still at 443, at 7100 its 440, or 7200 its 438, at 7300 it 429, at 7400 its 415. Why would you want to shift before 7300? To make the car go the fastest you wouldn't. No shifting at those high RPM's adds extra stress on everything, and can make other parts not so happy.
Now lets say the 205's made peak at 6400 and they made 440 peak. At 6500 437, at 6600 435, at 6700 430 at 6800 421 at 6900 412HP. No your starting to fall off of your peak number and should shift between 6700 and 6850, which is a lot less stressful on the motor.
If you dont understand this read it a few times and it will make since.
Originally Posted by SStheBest
uhh huh i get it...b/c when i shift ill be right back at the peak hp range...lol bound rap my *** around a tree.....thanks for the advice
Well you wont acturally be shifting back to your peak HP range unless you have some crazy stall converter.
Lets say you had a 3500-3800 stall with 3.73 gear in a A4 or a M6 with a 4.10 gear. (2 commonly used setup's)
Most people shifting at say 6500 RPM's will shift back down to lets just say 5250 RPM's.
This is where the bigger advantage would come in using the 225's (from what I understand, and with the right camshaft) Lets say for example you make 375 HP at 5250, and 410 at 5600. When using the 225's and spinning the motor higher once you shift your MPH is also higher causing your car to shift down to 5600 vs 5250. Now your making a extra 35+ HP throughout the entire race.
Its hard to figure out unless you go to the track and short shift on purpose.
To give you the best example jump in your car. Hold it in gear. Bring your RPM's to 4000 and mash the pedal.
Then do the same thing from 5000 RPM's. You will feel a difference, which of course is because at 5000 RPM's our cars make more power then at 4000 RPM's.
TECH Enthusiast
Joined: Jun 2003
Posts: 720
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From: So Cal
Originally Posted by Tony Mamo @ AFR
Flycutting is a must....
Tony M.
Tony M.
Last edited by Revelation222; Mar 28, 2005 at 07:39 PM.
Originally Posted by Revelation222
This is no matter what cam we run? Quick question. On a Forged 346 F1 ATI application. I am looking to run the F7 from Futral (224/228 114). Would it be better to run the 225's or get the 205's and have them "blower" ported by a reputable shop? I was thinking about the shrouding from the 225's as well as PvC between the two. Could you point me toward the better application? Also, would you recomend O-ringing either head? Thanks Tony.
Originally Posted by BrentB@TEA
Tony, can you post up flow numbers on a 3.9 bore comparring a 205 to 225. That way he can see the flow differences between the 2 cylinder heads. I believe I read that the current 225 was developed for a 4.00" bore and larger?
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
------------------------------------------------------------------------
And here is some 225 "small bore" intake flow information I took last week....similar to above...slightly better at a few of the liftpoints.
.200......152 CFM
.300......215 CFM
.400......261 CFM
.500......294 CFM
.550......306 CFM
.600......313 CFM
This is the exhaust comparison from the very same day (against a 205 for comparison purposes)
LIFT......205......225
.200......112......122
.300......170......179
.400......203......213
.500......221......230
.600......230......240
Last edited by Tony Mamo @ AFR; Mar 28, 2005 at 07:27 PM.
TECH Enthusiast
Joined: Jun 2003
Posts: 720
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From: So Cal
Originally Posted by Tony Mamo @ AFR
Copied and pasted from one of my responses in the "AFR 225 Thread"....
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
------------------------------------------------------------------------
And here is some 225 "small bore" intake flow information I took last week....similar to above...slightly better at a few of the liftpoints.
.200......152 CFM
.300......215 CFM
.400......261 CFM
.500......294 CFM
.550......306 CFM
.600......313 CFM
This is the exhaust comparison from the very same day (against a 205 for comparison purposes)
LIFT......205......225
.200......112......122
.300......170......179
.400......203......213
.500......221......230
.600......230......240
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
------------------------------------------------------------------------
And here is some 225 "small bore" intake flow information I took last week....similar to above...slightly better at a few of the liftpoints.
.200......152 CFM
.300......215 CFM
.400......261 CFM
.500......294 CFM
.550......306 CFM
.600......313 CFM
This is the exhaust comparison from the very same day (against a 205 for comparison purposes)
LIFT......205......225
.200......112......122
.300......170......179
.400......203......213
.500......221......230
.600......230......240
What about the flycutting? Would I need to do so with the 72cc 225's with the F7 (224/230 114) cam? Thanks alot guys.
Last edited by Revelation222; Mar 28, 2005 at 07:39 PM.
TECH Enthusiast
Joined: Dec 2004
Posts: 576
Likes: 0
From: Chattanooga
Originally Posted by Tony Mamo @ AFR
Copied and pasted from one of my responses in the "AFR 225 Thread"....
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
------------------------------------------------------------------------
And here is some 225 "small bore" intake flow information I took last week....similar to above...slightly better at a few of the liftpoints.
.200......152 CFM
.300......215 CFM
.400......261 CFM
.500......294 CFM
.550......306 CFM
.600......313 CFM
This is the exhaust comparison from the very same day (against a 205 for comparison purposes)
LIFT......205......225
.200......112......122
.300......170......179
.400......203......213
.500......221......230
.600......230......240
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
------------------------------------------------------------------------
And here is some 225 "small bore" intake flow information I took last week....similar to above...slightly better at a few of the liftpoints.
.200......152 CFM
.300......215 CFM
.400......261 CFM
.500......294 CFM
.550......306 CFM
.600......313 CFM
This is the exhaust comparison from the very same day (against a 205 for comparison purposes)
LIFT......205......225
.200......112......122
.300......170......179
.400......203......213
.500......221......230
.600......230......240
__________________afr205 on our bench
.100_______________64.1
.200______________140
.300______________203.4
.400______________250.1
.500______________282.9
.550______________296.5
.600______________303.4
Originally Posted by BrentB@TEA
Good comparrison. Our benchs are pretty similar. Ours reads a little higher than yours but pretty close.(it could have been the head) Do you flow with a clay radius also correct? I will post what we get out of the next ones we recieve. (225 and a 205 are on the way.)
__________________afr205 on our bench
.100_______________64.1
.200______________140
.300______________203.4
.400______________250.1
.500______________282.9
.550______________296.5
.600______________303.4
__________________afr205 on our bench
.100_______________64.1
.200______________140
.300______________203.4
.400______________250.1
.500______________282.9
.550______________296.5
.600______________303.4
From the TEA stuff I have seen here (at AFR) I would say that our intake flow is fairly close. We dont use clay, however, for any flowing of intake ports....much to inconsistent. We have a dedicated "LS" radiused inlet fixture that we use for all of our testing. I think the biggest discrepancy is the huge delta on the exhaust side between our equipment. As much as I would be flattered that our 205 heads flow 265+ on the exhaust, respectfully, I feel that is not the case. I'm sure its the combination of the different type of flow benches we each use, and the fact you guys use a straight tube when you flow an exhaust. Maybe we could get together sometime and figure out the actual delta between our equipment so it would be easier to share information related to flow numbers. The next time you guys order a CNC LS head, I could flow an intake and exhaust port on one hole and earmark it so you could flow the exact same port on your equipment. By the way, our 225 exhaust ports will go about 12-15 CFM better than our 205's on a 4.100 or larger bore....I think you guys will be impressed when you get a chance to flow one....especially considering its right off a CNC machine.
Regards,
Tony
Last edited by Tony Mamo @ AFR; Mar 29, 2005 at 11:59 AM.
