heads
Thread Starter
Teching In
Joined: Dec 2010
Posts: 5
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From: Tinley Park,IL
heads Hello, so I been getting into debates with my brother on what heads to go with on my build and thought I would post on here for suggestions. My plan is to go with the RHS Pro action 225cc cathedral heads (springs have a max .625 lift). My brother is telling me to buy ported 243 heads with bigger valves and save money. I've been told the brute forced induction cam (Dur @ .050 232 int 240 exh./ Lift .595 int .608 exh)with the RHS pro action heads, and a fast 92mm intake would work great together. Any input would be appreciated, Thanks
TECH Resident
Joined: Mar 2002
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From: North Las Vegas, NV
Honestly, I will tell you the following:
1. I don't own these heads.
2. I don't know anyone else with these heads.
3. I would seriously research these.
4. I would try to find someone that does own these heads and...
A. Get dyno comparisons from stock to RHS.
B. Get mph comparisons from stock to RHS.
Here is an article that I have in one of my old GM High Tech mag on them. I hope this helps you...
http://www.gmhightechperformance.com...t/viewall.html
1. I don't own these heads.
2. I don't know anyone else with these heads.
3. I would seriously research these.
4. I would try to find someone that does own these heads and...
A. Get dyno comparisons from stock to RHS.
B. Get mph comparisons from stock to RHS.
Here is an article that I have in one of my old GM High Tech mag on them. I hope this helps you...
http://www.gmhightechperformance.com...t/viewall.html
OP, I to have been considering the RHS pro action 225's, but with the comp 10925, which are the dual spring .660 max lift spring. My C5Z is sporting a similar cam, a Pat G spec'd .230/.230 .598/.608 w/ a 112 LSA. To save you some research I have already done, the RHS heads are cast by Dart, and once ported, will be some top rate heads, BUT that is once ported. Out of the box, they would out perform (CFM) stock 243's but they would not out perform a Ported and Polished 243. So, your brother is correct in his assessment, porting 243's will save you some cash and get you great performance. They may not out perform the RHS heads once they've been ported, but they will out perform them out of the box. Now again, I encourage you to do reaserch as much as you can, but this is how my research ended.
I don't know much about the RHS heads... but I do believe they are Dart 225. A decent head, but not the best. Not even close.
If you want LS6 heads:
Advanced Induction, Livernois, or TEA would be my choices. All make great power with the Ai ports running stock valves. Livernois or TEA can set up their heads with stock valves or larger stainless valves. All make pretty much the same power (+50rwhp) over stock LS1 heads. All are top notch as well. TSP is a budget alternative and can provide one stop shopping. But guess what? So can the others.
If you go aftermarket, I'd consider the following:
AFR 210s (updated 205s), TFS As Cast 220s, or Mast Small Bore LS3 220s. The AFRs are proven to make huge power on any combo over the last decade. The 210s simply put out another 5-10HP over the 205s.
The TFS As Cast get the nod over the 215s, simply because it's the same port, just cast vs CNC. It's 700 less for maybe 5-10HP less power. It's also cheaper than AFR.
Mast is the wildcard here. Their LS3 11-degree heads flow insane and are only a 220cc rectangle port (like the LS3) but outflow stock LS3s with a much smaller CSA and much smaller valves (and therefore are easier to cam). I haven't seen results from them, and they are expensive, but those could be the best heads you could put on a 3.9" bore. When I say best flowing: 274 @ .400; 318 @ .500; 333 @ .550; 342 @ .600. Power is more then flow numbers and comparing flow numbers doesn't mean ****. But those numbers are much higher @ .500+ than any other 3.9" bore head I've ever seen.
All of the aftermarket castings have one advantage over stock ported heads: more piston-to-valve clearance. The other stuff they talk about is marketing mumbo jumbo. The rolled valve angle on TFS and Mast heads provide more Piston-to-valve and the AFRs just have a different combustion chamber design that provides more room at the stock 15 degree angle.
Don't get sucked into marketing and internet hype. Take a look at each head I listed. Talk to the manufacturers. Then talk to shops that sell and install and tune a few of them. Get unbiased feedback from them. Don't talk to shops that only sell one or have their own brand they push. Talk to folks who install and tune this stuff. I think a pretty clear pattern will emerge on what heads are the best and which ones you should invest your cash in.
If you want LS6 heads:
Advanced Induction, Livernois, or TEA would be my choices. All make great power with the Ai ports running stock valves. Livernois or TEA can set up their heads with stock valves or larger stainless valves. All make pretty much the same power (+50rwhp) over stock LS1 heads. All are top notch as well. TSP is a budget alternative and can provide one stop shopping. But guess what? So can the others.
If you go aftermarket, I'd consider the following:
AFR 210s (updated 205s), TFS As Cast 220s, or Mast Small Bore LS3 220s. The AFRs are proven to make huge power on any combo over the last decade. The 210s simply put out another 5-10HP over the 205s.
The TFS As Cast get the nod over the 215s, simply because it's the same port, just cast vs CNC. It's 700 less for maybe 5-10HP less power. It's also cheaper than AFR.
Mast is the wildcard here. Their LS3 11-degree heads flow insane and are only a 220cc rectangle port (like the LS3) but outflow stock LS3s with a much smaller CSA and much smaller valves (and therefore are easier to cam). I haven't seen results from them, and they are expensive, but those could be the best heads you could put on a 3.9" bore. When I say best flowing: 274 @ .400; 318 @ .500; 333 @ .550; 342 @ .600. Power is more then flow numbers and comparing flow numbers doesn't mean ****. But those numbers are much higher @ .500+ than any other 3.9" bore head I've ever seen.
All of the aftermarket castings have one advantage over stock ported heads: more piston-to-valve clearance. The other stuff they talk about is marketing mumbo jumbo. The rolled valve angle on TFS and Mast heads provide more Piston-to-valve and the AFRs just have a different combustion chamber design that provides more room at the stock 15 degree angle.
Don't get sucked into marketing and internet hype. Take a look at each head I listed. Talk to the manufacturers. Then talk to shops that sell and install and tune a few of them. Get unbiased feedback from them. Don't talk to shops that only sell one or have their own brand they push. Talk to folks who install and tune this stuff. I think a pretty clear pattern will emerge on what heads are the best and which ones you should invest your cash in.
Thread Starter
Teching In
Joined: Dec 2010
Posts: 5
Likes: 0
From: Tinley Park,IL
I don't know much about the RHS heads... but I do believe they are Dart 225. A decent head, but not the best. Not even close.
If you want LS6 heads:
Advanced Induction, Livernois, or TEA would be my choices. All make great power with the Ai ports running stock valves. Livernois or TEA can set up their heads with stock valves or larger stainless valves. All make pretty much the same power (+50rwhp) over stock LS1 heads. All are top notch as well. TSP is a budget alternative and can provide one stop shopping. But guess what? So can the others.
If you go aftermarket, I'd consider the following:
AFR 210s (updated 205s), TFS As Cast 220s, or Mast Small Bore LS3 220s. The AFRs are proven to make huge power on any combo over the last decade. The 210s simply put out another 5-10HP over the 205s.
The TFS As Cast get the nod over the 215s, simply because it's the same port, just cast vs CNC. It's 700 less for maybe 5-10HP less power. It's also cheaper than AFR.
Mast is the wildcard here. Their LS3 11-degree heads flow insane and are only a 220cc rectangle port (like the LS3) but outflow stock LS3s with a much smaller CSA and much smaller valves (and therefore are easier to cam). I haven't seen results from them, and they are expensive, but those could be the best heads you could put on a 3.9" bore. When I say best flowing: 274 @ .400; 318 @ .500; 333 @ .550; 342 @ .600. Power is more then flow numbers and comparing flow numbers doesn't mean ****. But those numbers are much higher @ .500+ than any other 3.9" bore head I've ever seen.
All of the aftermarket castings have one advantage over stock ported heads: more piston-to-valve clearance. The other stuff they talk about is marketing mumbo jumbo. The rolled valve angle on TFS and Mast heads provide more Piston-to-valve and the AFRs just have a different combustion chamber design that provides more room at the stock 15 degree angle.
Don't get sucked into marketing and internet hype. Take a look at each head I listed. Talk to the manufacturers. Then talk to shops that sell and install and tune a few of them. Get unbiased feedback from them. Don't talk to shops that only sell one or have their own brand they push. Talk to folks who install and tune this stuff. I think a pretty clear pattern will emerge on what heads are the best and which ones you should invest your cash in.
If you want LS6 heads:
Advanced Induction, Livernois, or TEA would be my choices. All make great power with the Ai ports running stock valves. Livernois or TEA can set up their heads with stock valves or larger stainless valves. All make pretty much the same power (+50rwhp) over stock LS1 heads. All are top notch as well. TSP is a budget alternative and can provide one stop shopping. But guess what? So can the others.
If you go aftermarket, I'd consider the following:
AFR 210s (updated 205s), TFS As Cast 220s, or Mast Small Bore LS3 220s. The AFRs are proven to make huge power on any combo over the last decade. The 210s simply put out another 5-10HP over the 205s.
The TFS As Cast get the nod over the 215s, simply because it's the same port, just cast vs CNC. It's 700 less for maybe 5-10HP less power. It's also cheaper than AFR.
Mast is the wildcard here. Their LS3 11-degree heads flow insane and are only a 220cc rectangle port (like the LS3) but outflow stock LS3s with a much smaller CSA and much smaller valves (and therefore are easier to cam). I haven't seen results from them, and they are expensive, but those could be the best heads you could put on a 3.9" bore. When I say best flowing: 274 @ .400; 318 @ .500; 333 @ .550; 342 @ .600. Power is more then flow numbers and comparing flow numbers doesn't mean ****. But those numbers are much higher @ .500+ than any other 3.9" bore head I've ever seen.
All of the aftermarket castings have one advantage over stock ported heads: more piston-to-valve clearance. The other stuff they talk about is marketing mumbo jumbo. The rolled valve angle on TFS and Mast heads provide more Piston-to-valve and the AFRs just have a different combustion chamber design that provides more room at the stock 15 degree angle.
Don't get sucked into marketing and internet hype. Take a look at each head I listed. Talk to the manufacturers. Then talk to shops that sell and install and tune a few of them. Get unbiased feedback from them. Don't talk to shops that only sell one or have their own brand they push. Talk to folks who install and tune this stuff. I think a pretty clear pattern will emerge on what heads are the best and which ones you should invest your cash in.
