Cathedral Port Vs. Rectangular Port
What I'm saying is the LS3 heads have not been impressive until recently. The CSA is different with a rectangular port - so they can be bigger and not lose the kind of efficiency you might see out of a 320cfm, 250cc cathedral port.
However, they were only introduced in 08 and it's taken the aftermarket a few years to get them right. I think as we move forward, you'll see them putting out much higher flow numbers that start to separate them from the much more mature cathedral head products. Cathedrals still have a place. Say you want a 600HP motor - the cathedral provides much more torque and airspeed with the smaller, more optimized port.
But also, if you don't take advantage of the head, then you can't make use of it's strengths. A cam with only .450 lift doesn't take advantage of the cathedrals either. Does that mean the cathedral is worse than a SBC 23 degree head which might have a smaller port but similar flow in the .200 and .300 range? Of course not. And while the LSx platform has a larger cam core which allows better lobe design to add stability to the valvetrain, it's all part of making advances to make more and more power. Look at the LT series... Or things like the Low Lash Solid Roller... .700" lifts are easy and effective on street motors.
Progress. Progress. Progress.
However, they were only introduced in 08 and it's taken the aftermarket a few years to get them right. I think as we move forward, you'll see them putting out much higher flow numbers that start to separate them from the much more mature cathedral head products. Cathedrals still have a place. Say you want a 600HP motor - the cathedral provides much more torque and airspeed with the smaller, more optimized port.
But also, if you don't take advantage of the head, then you can't make use of it's strengths. A cam with only .450 lift doesn't take advantage of the cathedrals either. Does that mean the cathedral is worse than a SBC 23 degree head which might have a smaller port but similar flow in the .200 and .300 range? Of course not. And while the LSx platform has a larger cam core which allows better lobe design to add stability to the valvetrain, it's all part of making advances to make more and more power. Look at the LT series... Or things like the Low Lash Solid Roller... .700" lifts are easy and effective on street motors.
Progress. Progress. Progress.
What I'm saying is the LS3 heads have not been impressive until recently. The CSA is different with a rectangular port - so they can be bigger and not lose the kind of efficiency you might see out of a 320cfm, 250cc cathedral port.
However, they were only introduced in 08 and it's taken the aftermarket a few years to get them right. I think as we move forward, you'll see them putting out much higher flow numbers that start to separate them from the much more mature cathedral head products. Cathedrals still have a place. Say you want a 600HP motor - the cathedral provides much more torque and airspeed with the smaller, more optimized port.
But also, if you don't take advantage of the head, then you can't make use of it's strengths. A cam with only .450 lift doesn't take advantage of the cathedrals either. Does that mean the cathedral is worse than a SBC 23 degree head which might have a smaller port but similar flow in the .200 and .300 range? Of course not. And while the LSx platform has a larger cam core which allows better lobe design to add stability to the valvetrain, it's all part of making advances to make more and more power. Look at the LT series... Or things like the Low Lash Solid Roller... .700" lifts are easy and effective on street motors.
Progress. Progress. Progress.
However, they were only introduced in 08 and it's taken the aftermarket a few years to get them right. I think as we move forward, you'll see them putting out much higher flow numbers that start to separate them from the much more mature cathedral head products. Cathedrals still have a place. Say you want a 600HP motor - the cathedral provides much more torque and airspeed with the smaller, more optimized port.
But also, if you don't take advantage of the head, then you can't make use of it's strengths. A cam with only .450 lift doesn't take advantage of the cathedrals either. Does that mean the cathedral is worse than a SBC 23 degree head which might have a smaller port but similar flow in the .200 and .300 range? Of course not. And while the LSx platform has a larger cam core which allows better lobe design to add stability to the valvetrain, it's all part of making advances to make more and more power. Look at the LT series... Or things like the Low Lash Solid Roller... .700" lifts are easy and effective on street motors.
Progress. Progress. Progress.
Now that you brought up low lash solid roller and .700" lift. Something came to my mind while you said that. Is it possible to run a solid roller on the street without having to adjust the valve lash like a HYD roller cam? Also what is the highest lift cam can one run without having valve spring problems? THANKS!
That's the idea of them. Kip @ Cam Motion has said they typically can run 20-25k miles before you have to adjust or even check lash. With an aggressive hydraulic, you are probably swapping springs by that point and checking much more often.
I say if you do the low lash solid roller, you can do tall Proform valve covers with relocated coils and it would be easy to pull the cover and do a quick check every time you change your oil.
I would be comfortable running .700" lift on the street. If the heads don't stall out at .700 or just past it, you could even run a .750 or so. After that, you get into much more expensive valve spring options. The 1209s from PAC are good to .750 and are no more expensive than the 1207s which are good to 700. And work well with those cams.
I say if you do the low lash solid roller, you can do tall Proform valve covers with relocated coils and it would be easy to pull the cover and do a quick check every time you change your oil.
I would be comfortable running .700" lift on the street. If the heads don't stall out at .700 or just past it, you could even run a .750 or so. After that, you get into much more expensive valve spring options. The 1209s from PAC are good to .750 and are no more expensive than the 1207s which are good to 700. And work well with those cams.
That's the idea of them. Kip @ Cam Motion has said they typically can run 20-25k miles before you have to adjust or even check lash. With an aggressive hydraulic, you are probably swapping springs by that point and checking much more often.
I say if you do the low lash solid roller, you can do tall Proform valve covers with relocated coils and it would be easy to pull the cover and do a quick check every time you change your oil.
I would be comfortable running .700" lift on the street. If the heads don't stall out at .700 or just past it, you could even run a .750 or so. After that, you get into much more expensive valve spring options. The 1209s from PAC are good to .750 and are no more expensive than the 1207s which are good to 700. And work well with those cams.
I say if you do the low lash solid roller, you can do tall Proform valve covers with relocated coils and it would be easy to pull the cover and do a quick check every time you change your oil.
I would be comfortable running .700" lift on the street. If the heads don't stall out at .700 or just past it, you could even run a .750 or so. After that, you get into much more expensive valve spring options. The 1209s from PAC are good to .750 and are no more expensive than the 1207s which are good to 700. And work well with those cams.
Thanks for the INFO. Now I learn something.
On The Tree
Joined: Mar 2015
Posts: 154
Likes: 12
What I'm saying is the LS3 heads have not been impressive until recently. The CSA is different with a rectangular port - so they can be bigger and not lose the kind of efficiency you might see out of a 320cfm, 250cc cathedral port.
However, they were only introduced in 08 and it's taken the aftermarket a few years to get them right. I think as we move forward, you'll see them putting out much higher flow numbers that start to separate them from the much more mature cathedral head products. Cathedrals still have a place. Say you want a 600HP motor - the cathedral provides much more torque and airspeed with the smaller, more optimized port.
But also, if you don't take advantage of the head, then you can't make use of it's strengths. A cam with only .450 lift doesn't take advantage of the cathedrals either. Does that mean the cathedral is worse than a SBC 23 degree head which might have a smaller port but similar flow in the .200 and .300 range? Of course not. And while the LSx platform has a larger cam core which allows better lobe design to add stability to the valvetrain, it's all part of making advances to make more and more power. Look at the LT series... Or things like the Low Lash Solid Roller... .700" lifts are easy and effective on street motors.
Progress. Progress. Progress.
However, they were only introduced in 08 and it's taken the aftermarket a few years to get them right. I think as we move forward, you'll see them putting out much higher flow numbers that start to separate them from the much more mature cathedral head products. Cathedrals still have a place. Say you want a 600HP motor - the cathedral provides much more torque and airspeed with the smaller, more optimized port.
But also, if you don't take advantage of the head, then you can't make use of it's strengths. A cam with only .450 lift doesn't take advantage of the cathedrals either. Does that mean the cathedral is worse than a SBC 23 degree head which might have a smaller port but similar flow in the .200 and .300 range? Of course not. And while the LSx platform has a larger cam core which allows better lobe design to add stability to the valvetrain, it's all part of making advances to make more and more power. Look at the LT series... Or things like the Low Lash Solid Roller... .700" lifts are easy and effective on street motors.
Progress. Progress. Progress.
On a 402-416 it's really a choice between three heads:
Frankenstein TFS 237s
Frankenstein TFS LS3 255s
Frankenstein Ported Stage 2 LS3 OE Heads
Cheapest is the OE heads.
But all will support 416 to 7500. No problem. And all will make more than 600. Talk to Chris Frank. He'll probably say his Stage 2 heads would be tough to beat. But may sway you to the Cathedral ports. The LS3s flow so much more air, but it doesn't manifest as additional power.
Frankenstein TFS 237s
Frankenstein TFS LS3 255s
Frankenstein Ported Stage 2 LS3 OE Heads
Cheapest is the OE heads.
But all will support 416 to 7500. No problem. And all will make more than 600. Talk to Chris Frank. He'll probably say his Stage 2 heads would be tough to beat. But may sway you to the Cathedral ports. The LS3s flow so much more air, but it doesn't manifest as additional power.
then him and Mamo need to offer street outlaw versions without the giant "look at me" logos on them.
If you're trying to pass off a 440 incher with a "money maker" kit as a 346 NA with cathedrals, it helps to remove all signs of awesomeness. Rusty E-Bay headers will help too....Lol
If you're trying to pass off a 440 incher with a "money maker" kit as a 346 NA with cathedrals, it helps to remove all signs of awesomeness. Rusty E-Bay headers will help too....Lol
Last edited by A.R. Shale Targa; Jul 19, 2015 at 03:57 PM. Reason: spelling
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Joined: Sep 2004
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then hew and Mamo need to offer street outlaw versions without the giant "look at me" logos on them.
If you're trying to pass off a 440 incher with a "money maker" kit as a 346 NA with cathedrals, it helps to remove all signs of awesomeness. Rusty E-Bay headers will help to....LOL
If you're trying to pass off a 440 incher with a "money maker" kit as a 346 NA with cathedrals, it helps to remove all signs of awesomeness. Rusty E-Bay headers will help to....LOL
If your feeling real ambitious you can machine a hole in the end pads for the OEM freeze plugs for total stealth!
I love an innocent looking deal that runs hard.....its great seeing the faces of the guys you just beat!
=)
__________________
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
I will say this - there's a reason I haven't posted a dyno or track times on here. Not because they suck. But because you don't need to know. I have a well-documented build thread. And I left out quite a bit... but put in there the things that I think most folks want to know about. It's the things you don't know that make money runs interesting... and why I am looking at more already.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
Cathedral Port Vs. Rectangular Port take a closer at a rectangle port head, you will see the intake rocker arms have an offset to account for the pushrods being relocated.
Personally, I think it's important that people post results to help others compare or build, both dyno and track. You see high dyno all the time. I put much more faith in track result than dynos (especially trap speeds) There are a ton of high dyno cars that don't perform. Too bad everybody could post track results at a reasonable good DA, maybe 800 feet. Also, seems like people don't have a clue as to race weights either posting ridiculous numbers. I think it is true a lot of people hope there cars perform better than they do so they are more reluctant to post results, including myself. I was hoping to dyno 560-570 rwhp and trap 135. Guess what, I didn't. The poster that questioned the three heads listed was building an awesome motor with Frankenstein LS7 heads. Once again he was hoping for a lot more then he ended up with. He had dyno numbers but no track numbers. The car was totaled I believe. I was wanted to compare his results so I might make a change although he had a much lighter 5th generation ZO6.
And just for comparison:
235/251 cam in both cases personally here:
FRH - 554/490 whp
PRC 265's - 583/526 whp
On a 150 shot:
FRH - 700/620whp
PRC's - 753/771whp
So, yes I'm not a big proponent of FRH's work, especially for the money. I spent just over 1/2 for PRC's work on my stockers and as you see the results speak for themselves.