AFR small bore 225s vs AFR 205s on a 346.
#1
AFR small bore 225s vs AFR 205s on a 346.
Interesting gains on the flow bench and on the dyno. On the flow bench with a 3.900 bore, the AFR 225 small bore heads were identical in flow to the 205s from .100"-.400" lift.
Gains of the 225s over the 205s at higher lifts:
At .450" +11
At .500" +15
At .550" +23
At .600" +21
At .650" +31
Because I run a .650" lift cam, we felt my car would be a good candidate to take advantage of the killer increase in flow at higher lifts.
Here's the kicker though. My car has a razor sharp speed density tune I spent literally MONTHS perfecting. Now, I was bolting up a better flow set of heads and I couldn't rely on a MAF to compensate for the extra airflow.
For a baseline program, we added 5% to the VE tables at 90, 100kPa (figuring a 5% flow increase and power increase). When we hit the dyno, we were WAY lean. When it was all said and done, we wound up needing to add over 15% fuel to the top end numbers. The motor was flowing more air and definitely wanting lots more fuel. Surprisingly, we only got 5 rwhp gain and 5 rwtq gain from the initial pulls before we had to call it a day.
The 225s mirrored the 205s at every rpm to about 4000 rpm, then they started pulling away. Funny thing is, the motor now wants 15% more fuel, but was only making 1% more power. All we had time to adjust was fuel. We did not have time to mess with timing. Since the motor wants all that extra fuel, the power had to be there, I'm just going to have to make another trip to the chassis dyno to work the timing end. FWIW, I'm running 26 degrees of timing at peak torque and 29 degrees of timing at peak power. That's what the 205s liked. I'm not sure what the 225s are going to like. More timing? Less timing? Based on the increased airflow upstairs and the coinciding appetite for fuel, I feel the power once tuned, will exceed my prediction of 15 rwhp gain, but again, speed density tuning is such a balancing act. I picked up 10 extra rwhp by sharping up my 205 tune. I feel that with more time on the dyno and on the road, I will unleash all the BTUs that are hiding in all that extra airflow and fuel.
On a sidenote, my low rpm fueling was about 5% too rich, meaning the 225s don't want as much fuel downstairs (because of the lower airspeed I guess). Wierd: 5% less fuel at low rpm and 15% more fuel at high rpm. Needless to say, my VE tables are much more spread out than they used to be. I will report back after I have my tuning closer. Sorry we ran out of time.
So for those who look to the end of a post for the conclusion of a story, so far, I picked up 5 rwhp/5rwtq from 4500 rpm to redline over the 205s and lost 0 below that. With more tuning, we will find the rest of the hp. Looks very promising.
Gains of the 225s over the 205s at higher lifts:
At .450" +11
At .500" +15
At .550" +23
At .600" +21
At .650" +31
Because I run a .650" lift cam, we felt my car would be a good candidate to take advantage of the killer increase in flow at higher lifts.
Here's the kicker though. My car has a razor sharp speed density tune I spent literally MONTHS perfecting. Now, I was bolting up a better flow set of heads and I couldn't rely on a MAF to compensate for the extra airflow.
For a baseline program, we added 5% to the VE tables at 90, 100kPa (figuring a 5% flow increase and power increase). When we hit the dyno, we were WAY lean. When it was all said and done, we wound up needing to add over 15% fuel to the top end numbers. The motor was flowing more air and definitely wanting lots more fuel. Surprisingly, we only got 5 rwhp gain and 5 rwtq gain from the initial pulls before we had to call it a day.
The 225s mirrored the 205s at every rpm to about 4000 rpm, then they started pulling away. Funny thing is, the motor now wants 15% more fuel, but was only making 1% more power. All we had time to adjust was fuel. We did not have time to mess with timing. Since the motor wants all that extra fuel, the power had to be there, I'm just going to have to make another trip to the chassis dyno to work the timing end. FWIW, I'm running 26 degrees of timing at peak torque and 29 degrees of timing at peak power. That's what the 205s liked. I'm not sure what the 225s are going to like. More timing? Less timing? Based on the increased airflow upstairs and the coinciding appetite for fuel, I feel the power once tuned, will exceed my prediction of 15 rwhp gain, but again, speed density tuning is such a balancing act. I picked up 10 extra rwhp by sharping up my 205 tune. I feel that with more time on the dyno and on the road, I will unleash all the BTUs that are hiding in all that extra airflow and fuel.
On a sidenote, my low rpm fueling was about 5% too rich, meaning the 225s don't want as much fuel downstairs (because of the lower airspeed I guess). Wierd: 5% less fuel at low rpm and 15% more fuel at high rpm. Needless to say, my VE tables are much more spread out than they used to be. I will report back after I have my tuning closer. Sorry we ran out of time.
So for those who look to the end of a post for the conclusion of a story, so far, I picked up 5 rwhp/5rwtq from 4500 rpm to redline over the 205s and lost 0 below that. With more tuning, we will find the rest of the hp. Looks very promising.
__________________
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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#4
Originally Posted by Drew778
So, you gained 5 rwhp?
__________________
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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#6
Originally Posted by rosm187
looking to hit 500whp N/A 346? whats it run at the track, if u've run it yet
Trending Topics
#9
TECH Regular
iTrader: (1)
Join Date: Jan 2005
Location: Middleboro Ma.
Posts: 495
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Patrick G
500rwhp N/A with a medium size cam would be nice, but not my ultimate goal. I just want a super streetable package that makes strong power everywhere. I had it with the AFR 205s. I hope to have even more of it with the 225s.
#11
Originally Posted by zo6vetteman2003
With the 225's there may be a drop in low end torque, according to what I have seen with a 346ci.
#12
10 Second Club
iTrader: (5)
Join Date: Nov 2003
Location: Ft. Lauderdale, FL
Posts: 1,649
Likes: 0
Received 0 Likes
on
0 Posts
Patrick, sure sounds like there’s another 10 hp in it.
What lifters, rockers and valve springs are you running?
Is there any chance that you are getting valve float with the heavier 2.080 valves?
Did you rematch port the intake to the 225’s?
Good luck, you’ll find it!
Keep us posted.
Bob
What lifters, rockers and valve springs are you running?
Is there any chance that you are getting valve float with the heavier 2.080 valves?
Did you rematch port the intake to the 225’s?
Good luck, you’ll find it!
Keep us posted.
Bob
#13
Originally Posted by SlickVert
Patrick, sure sounds like there’s another 10 hp in it.
What lifters, rockers and valve springs are you running?
Is there any chance that you are getting valve float with the heavier 2.080 valves?
Did you rematch port the intake to the 225’s?
Good luck, you’ll find it!
Keep us posted.
Bob
What lifters, rockers and valve springs are you running?
Is there any chance that you are getting valve float with the heavier 2.080 valves?
Did you rematch port the intake to the 225’s?
Good luck, you’ll find it!
Keep us posted.
Bob
__________________
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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
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
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
Last edited by Patrick G; 02-06-2006 at 10:42 AM.
#14
TECH Fanatic
iTrader: (3)
Join Date: Jun 2004
Location: Dayton, OH
Posts: 1,844
Likes: 0
Received 0 Likes
on
0 Posts
Interesting experiment, I'll keep an eye on this one.
The only problem I see is that your cam is matched to the 205's and I don't think that cam is capable of showing the full potential of 225's. I would think something in the mid 240's matched to the 225 would be more ideal, especially in the upper RPM's.
The only problem I see is that your cam is matched to the 205's and I don't think that cam is capable of showing the full potential of 225's. I would think something in the mid 240's matched to the 225 would be more ideal, especially in the upper RPM's.
#15
Originally Posted by Louie83
Interesting experiment, I'll keep an eye on this one.
The only problem I see is that your cam is matched to the 205's and I don't think that cam is capable of showing the full potential of 225's. I would think something in the mid 240's matched to the 225 would be more ideal, especially in the upper RPM's.
The only problem I see is that your cam is matched to the 205's and I don't think that cam is capable of showing the full potential of 225's. I would think something in the mid 240's matched to the 225 would be more ideal, especially in the upper RPM's.
#16
12 Second Club
iTrader: (4)
Join Date: Jan 2004
Location: NJ
Posts: 929
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Patrick G
Interesting gains on the flow bench and on the dyno. On the flow bench with a 3.900 bore, the AFR 225 small bore heads were identical in flow to the 205s from .100"-.400" lift.
Gains of the 225s over the 205s at higher lifts:
At .450" +11
At .500" +15
At .550" +23
At .600" +21
At .650" +31
Gains of the 225s over the 205s at higher lifts:
At .450" +11
At .500" +15
At .550" +23
At .600" +21
At .650" +31
Originally Posted by Tony Mamo @ AFR
AFR PN 1660
Flowtested on a 3.900 bore
Radiused Inlet / Exh. tested with 1.875 curved pipe
NOTE: "Stock" combustion chamber volume is 65 cc's. They can be safely milled to the mid/high 50's but at the expense of slight loss in flow.
(Also including AFR 205 #'s for comparison (PN 1510)
INTAKE #'s
LIFT.....225cc....205cc
.200......141......140
.300......205......200
.400......252......251
.500......287......281
.550......302......292
.600......310......298
.650......317......N/A
EXHAUST #'s (w/ pipe)
.200......116......112
.300......171......170
.400......204......203
.500......222......221
.600......232......230
.650......237......234
Flowtested on a 3.900 bore
Radiused Inlet / Exh. tested with 1.875 curved pipe
NOTE: "Stock" combustion chamber volume is 65 cc's. They can be safely milled to the mid/high 50's but at the expense of slight loss in flow.
(Also including AFR 205 #'s for comparison (PN 1510)
INTAKE #'s
LIFT.....225cc....205cc
.200......141......140
.300......205......200
.400......252......251
.500......287......281
.550......302......292
.600......310......298
.650......317......N/A
EXHAUST #'s (w/ pipe)
.200......116......112
.300......171......170
.400......204......203
.500......222......221
.600......232......230
.650......237......234
#17
SN95 Director
iTrader: (16)
Originally Posted by badaSS346
Where did you get those flow numbers? Tony M posted this.
These are not as dramatic gains as what you have and i just want to be sure that i am using accurate information to make a choice.
These are not as dramatic gains as what you have and i just want to be sure that i am using accurate information to make a choice.
#18
Originally Posted by badaSS346
Where did you get those flow numbers? Tony M posted this.
These are not as dramatic gains as what you have and i just want to be sure that i am using accurate information to make a choice.
These are not as dramatic gains as what you have and i just want to be sure that i am using accurate information to make a choice.
#19
12 Second Club
iTrader: (4)
Join Date: Jan 2004
Location: NJ
Posts: 929
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by jrp
i would assume that patrick flow tested his 205's vs the new 225's using the same testing apparatus and procedure. also, Tony err's on the conservative side with his numbers.
Paul
#20
Two things to remember: Tony's flow numbers are of both heads unmilled. Both my 205s and 225s were milled .030". The milling affects the flow numbers perhaps more on the 205s than the 225s. Also, Thunder Racing uses a Superflow 1020 bench while AFR uses a SF 600. The numbers do vary from bench to bench. We wanted to see the delta from one head to another. That's what I posted.