heads
Thread Starter
Intermediate
Joined: Nov 2010
Posts: 28
Likes: 0
From: michigan
heads
Have a 406sbc, rpm performer rpm top end kit, block decked, forged rotating assembly, 6" rods, dish pistons {might want giggle juice later} heads are 64cc, would changing heads to afr's be worth the $$, street machine, already has gobs of torque.
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I really don't follow the mindless sheep on products that just because they have a better advertisement campaign claiming to be the best thing since sliced bread.
Yes, I do believe that AFR did their home work on high flow for a given cc of port volume. But they also have some very negative aspects. spark plug location.....lack of oil return............valve covers and valve stem seals swimming in oil
All kind of things that they knew about 10 years ago and they don't care because the mindless public touts them as the best.
Higher CFM heads will give your motor a higher average HP across the rpm range. But you have to figure out cost per HP
Yes, I do believe that AFR did their home work on high flow for a given cc of port volume. But they also have some very negative aspects. spark plug location.....lack of oil return............valve covers and valve stem seals swimming in oil
All kind of things that they knew about 10 years ago and they don't care because the mindless public touts them as the best.
Higher CFM heads will give your motor a higher average HP across the rpm range. But you have to figure out cost per HP
Instructor
Joined: Nov 2003
Posts: 154
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From: NJ
I installed a pair of AFR 180's on my 355. Did I pay too much? Who knows. They do work as advertised with no oiling problems. I'm not nor do I pretend to be an expert on engines. I know what worked for my combo and that's it. AFR makes a good product. So does, Brodix, Dart, Edelbrock and a ton of head rebuilders. It's a matter of choice. I agree with GKull, the more air in for your combo the better.
Drifting
Joined: Dec 2005
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From: NORTHEAST
http://www.profilerperformance.com/sbc-heads-176.html
Race Director
Joined: Jun 2000
Posts: 10,039
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From: FL
The Edelbrock RPM heads are good on a street 350 max 6000 rpm. 170cc runners. Way to small for a 406. If you don't want AFR, look at Brodix or Dart. Even the Edelbrock Victor JR heads would breathe better on this application.
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O
#60899 | #60909 | #60999
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 66 129 188 228 240 241 -
Exhaust 55 98 131 152 162 168 -
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Race Director
Joined: Apr 2000
Posts: 17,673
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
The Edelbrock flow numbers are very poor even for 350 ci motors. those are only marginally better than stock 2.02/1.60's Your 406 would really wake up with heads that flow over 300 cfm
Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O
#60899 | #60909 | #60999
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 66 129 188 228 240 241 -
Exhaust 55 98 131 152 162 168 -
Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O
#60899 | #60909 | #60999
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 66 129 188 228 240 241 -
Exhaust 55 98 131 152 162 168 -
Just for fun here it is on the dyno
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,444
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
That is how our dyno at the shop is set up. Just roll it into place and open the door for the exhaust. Everything out in the open. That is how I got my leg bone shattered right below my knee cap when that sorry *** British Jaguar damper broke into three pieces
Thread Starter
Intermediate
Joined: Nov 2010
Posts: 28
Likes: 0
From: michigan
flow
The Edelbrock flow numbers are very poor even for 350 ci motors. those are only marginally better than stock 2.02/1.60's Your 406 would really wake up with heads that flow over 300 cfm
Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O
#60899 | #60909 | #60999
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 66 129 188 228 240 241 -
Exhaust 55 98 131 152 162 168 -
Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O
#60899 | #60909 | #60999
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 66 129 188 228 240 241 -
Exhaust 55 98 131 152 162 168 -
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
im making 440hp at the rear wheels (383) on a set of World SportsmanII's that have been ported polished and port-matched....
so... World.... take a look at what they have.... good price, good selection, good product.
so... World.... take a look at what they have.... good price, good selection, good product.
Race Director
Joined: Apr 2000
Posts: 17,673
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Race Director
Joined: Apr 2000
Posts: 17,673
Likes: 199
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Sportsman II heads are often overlooked. They are great heads, I made 300RWHP with my 355ci L48 with those heads. I like them they will support 500HP out of the box and they are not expensive but have gone up considerably since I bought a set over 10 years ago
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,444
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
The Rule on heads is: No matter what CC or who ported or designed them, the ultimate limitation is the valve sizes. 2.02 inch intake is just too small. The heads flowing over 300 are 2.08 or 2.10 inches
HEAD FLOW @ .600 LIFT
245 intake, 165 exhaust (Super Flow 1050)
260 intake, 176 exhaust (Super Flow 600)
All heads flowed with a standard .750" intake plate, without exhaust tube, and 28" of water.
Last edited by gkull; Dec 10, 2010 at 05:49 PM.
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
From the World products site. world do not flow very either for a 200cc head. P&P might be worth an additional 10-15 cfm. Also some companies use a bigger bore size like 4.125 and exhaust test pipes to inflate their claimed flow rates.
The Rule on heads is: No matter what CC or who ported or designed them, the ultimate limitation is the valve sizes. 2.02 inch intake is just too small. The heads flowing over 300 are 2.08 or 2.10 inches
HEAD FLOW @ .600 LIFT
245 intake, 165 exhaust (Super Flow 1050)
260 intake, 176 exhaust (Super Flow 600)
All heads flowed with a standard .750" intake plate, without exhaust tube, and 28" of water.
The Rule on heads is: No matter what CC or who ported or designed them, the ultimate limitation is the valve sizes. 2.02 inch intake is just too small. The heads flowing over 300 are 2.08 or 2.10 inches
HEAD FLOW @ .600 LIFT
245 intake, 165 exhaust (Super Flow 1050)
260 intake, 176 exhaust (Super Flow 600)
All heads flowed with a standard .750" intake plate, without exhaust tube, and 28" of water.
I was TOLD, after the porting i am right at 300 on intake... and they clam that the world heads have a lot of meat on them to port, they also said that they can make the sportsman II's flow much better than they can make an Edelbrock RPM heads flow... This is there clams, not mine... but my HP seems to go along with this.... the guys name was Toby....
But that being said George, you are by far a greater expert in this area than I..Hands down.. I am just relaying what i was told... and the results...
Last edited by pauldana; Dec 10, 2010 at 06:13 PM.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,444
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I guess thats the reason for the porting... http://www.valleyhead.com/racing.html
I was TOLD, after the porting i am right at 300 on intake... and they clam that the world heads have a lot of meat on them to port, the also said that they can make the sportsman II's flow much better than they cam make an Edelbrock RPM head flow... This is there clams, not mine... but my HP seems to go along with this.... the guys name was Toby....
But that being said George, you are by far a greater expert in this area than I..Hands down.. I am just relaying what i was told... and the results...
I was TOLD, after the porting i am right at 300 on intake... and they clam that the world heads have a lot of meat on them to port, the also said that they can make the sportsman II's flow much better than they cam make an Edelbrock RPM head flow... This is there clams, not mine... but my HP seems to go along with this.... the guys name was Toby....
But that being said George, you are by far a greater expert in this area than I..Hands down.. I am just relaying what i was told... and the results...
So you don't really have SPII's
Thread Starter
Intermediate
Joined: Nov 2010
Posts: 28
Likes: 0
From: michigan
size matters
I guess thats the reason for the porting... http://www.valleyhead.com/racing.html
I was TOLD, after the porting i am right at 300 on intake... and they clam that the world heads have a lot of meat on them to port, they also said that they can make the sportsman II's flow much better than they can make an Edelbrock RPM heads flow... This is there clams, not mine... but my HP seems to go along with this.... the guys name was Toby....
But that being said George, you are by far a greater expert in this area than I..Hands down.. I am just relaying what i was told... and the results...
I was TOLD, after the porting i am right at 300 on intake... and they clam that the world heads have a lot of meat on them to port, they also said that they can make the sportsman II's flow much better than they can make an Edelbrock RPM heads flow... This is there clams, not mine... but my HP seems to go along with this.... the guys name was Toby....
But that being said George, you are by far a greater expert in this area than I..Hands down.. I am just relaying what i was told... and the results...