Heads For 368+ Cubic Inch LSx
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Heads For 368+ Cubic Inch LSx This is just for fun, but one day, I'd love to build a big cubic inch LSx. If money was not a limiting factor, what cylinder heads would you run on a 368ci+ LSx? I would assume everyone will agree an aftermarket LS7 style head would be best, but there are big cathedral port options out there, like the MAST 295cc cathedral heads. Just curious what you guys would choose and why. Some heads that come to mind for me would be the Brodix STS BR7 285cc heads and RHS Pro-Elite LS7 heads.
Last edited by Rise of the Phoenix; Jun 8, 2016 at 07:08 AM.
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If money is not a factor, at least a 4.155 bore
4" stroke, the mast cathederals you mention.
The flow numbers are there for top end
and have a little more under the curve with
cathederal port, you can put a fast truck 102 intake, then a cam to suit heads and
cubic inches. Just my .02
4" stroke, the mast cathederals you mention.
The flow numbers are there for top end
and have a little more under the curve with
cathederal port, you can put a fast truck 102 intake, then a cam to suit heads and
cubic inches. Just my .02
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I was unaware MAST, or anyone for that matter, made that big of a cathedral port head until a few days ago. I'm just curious how those heads would stack up against the Brodix STS Br7 285cc LS7 style heads. I'd say the MAST cathedrals would probably do better under the curve, but I'm sure they will give up HP on the top end. How much, I'm not sure.
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What would be the intended use of the motor ? Street car, street/strip, drag only, standing mile, autocross... etc?
I'm a firm believer that each head has its own ups and down for each application.
I'm a firm believer that each head has its own ups and down for each application.
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While this is just a "fun conversation" for the time being, one day I really would love to have a big cubic inch motor for my WS6. What I would use it for would be street/strip use, with the emphasis being more toward the radical side. Hydraulic roller would be the way I'd go for a build like this if that helps.
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I was speaking with a rep at mast, he told me
with the cathederals you still get all the top
end a street setup can feed, plus you get
some under the curve, and with the 102
truck fast manifold it really shines, he had
nothing to gain either way, the 295 cathederals
and 305 LS7 head cost the same. He said the
velocity had something to do with it, I can't
remember, and I am in now way trying to say
I know about it, just what I was told. And seems
like the head comparison articals I have read
Mast always wins.
with the cathederals you still get all the top
end a street setup can feed, plus you get
some under the curve, and with the 102
truck fast manifold it really shines, he had
nothing to gain either way, the 295 cathederals
and 305 LS7 head cost the same. He said the
velocity had something to do with it, I can't
remember, and I am in now way trying to say
I know about it, just what I was told. And seems
like the head comparison articals I have read
Mast always wins.
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With their 12* port angle and 2.250"/1.60" valves, there's no reason to believe that the 295cc cathedrals can't be on par with the Mast 285cc LS7 heads.....or any other similarly sized LS7 head.
KW
EDIT:.....My Point Exactly....see below.
I was speaking with a rep at mast, he told me with the cathederals you still get all the top end a street setup can feed, plus you get some under the curve, and with the 102 truck fast manifold it really shines, he had nothing to gain either way, the 295 cathederals and 305 LS7 head cost the same. He said the velocity had something to do with it.......
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Well, that's pretty much what I was thinking when I found out about their 295cc cathedral heads. If this were not a street car and a 1/8th and 1/4 mile track car only, would that change your minds regarding the heads?
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You think the MAST 305cc heads are better than the Brodix heads? Have you ever checked out the Frankenstein Edelbrock LS-Reaper heads? Those would be some bad *** heads on a big cube LSx.
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http://www.superchevy.com/how-to/eng...ylinder-heads/
http://www.hotrod.com/how-to/engine/...top-ls7-heads/
http://www.dragzine.com/tech-stories...orts-ls-heads/ 3 good articles. but if I could buy my heads over again it would be Mast 295 cathedrals.
http://www.hotrod.com/how-to/engine/...top-ls7-heads/
http://www.dragzine.com/tech-stories...orts-ls-heads/ 3 good articles. but if I could buy my heads over again it would be Mast 295 cathedrals.
Last edited by slogo; Jun 7, 2016 at 06:00 PM.
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I would love to see real world results from those big mast cathedral heads... with such a big intake runner and valve size I wonder would it be tricky to get the cam specs on point ?
My favorite builds is big cube setups so let's keep this thread alive
My favorite builds is big cube setups so let's keep this thread alive
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I saw on FB where a guy had just received his MAST 295cc cathedral port heads. I believe they were going on a big cube turbo build. I would personally love to see them on a 368ci NA setup running around 13.5:1 or 14:1 compression.
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Either ported or non ported with WCCH cnc port program.
The newer Richard 290cc* heads are the Bomb looks just like Chris @ FRS heads,
as both use All Pro castings and look better to me than Mast or any other for that matter.
http://proheads.com/WCCH_All_Pro%20-1.html
Funny thing is I've read on Yellow Bullet about some guy buying Pro Comp ls 7 non Cnc casting and getting them re worked for less than 1800 bucks for a Small bore. He was beat up on for the purchase but was able to get them and beat on the idea of: If money was not a limiting factor, by cutting the price by more than 50% for Cnc'ed Ls 7 heads.
The newer Richard 290cc* heads are the Bomb looks just like Chris @ FRS heads,
as both use All Pro castings and look better to me than Mast or any other for that matter.
http://proheads.com/WCCH_All_Pro%20-1.html
Funny thing is I've read on Yellow Bullet about some guy buying Pro Comp ls 7 non Cnc casting and getting them re worked for less than 1800 bucks for a Small bore. He was beat up on for the purchase but was able to get them and beat on the idea of: If money was not a limiting factor, by cutting the price by more than 50% for Cnc'ed Ls 7 heads.
Last edited by Wasabi; Jun 8, 2016 at 10:59 AM.
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KCS do you think the TFS heads could be opened up that much as far as CC size of the MAST heads as someone could get them as you and have them done? That's how dreams become reality.
As the short block prices are not bad for a given size displacement engine anywhere from $6500 to around $8500 bucks gets you a well built short block. Which block is the question, and for how much is the Vanishing Point: 4.100+ over bores. Because all the guts of the LS-platform are on par with a typical SBC. I understand we are dreaming but somethings can become a reality if you could purchase a aftermarket block.
As the short block prices are not bad for a given size displacement engine anywhere from $6500 to around $8500 bucks gets you a well built short block. Which block is the question, and for how much is the Vanishing Point: 4.100+ over bores. Because all the guts of the LS-platform are on par with a typical SBC. I understand we are dreaming but somethings can become a reality if you could purchase a aftermarket block.
As the short block prices are not bad for a given size displacement engine anywhere from $6500 to around $8500 bucks gets you a well built short block. Which block is the question, and for how much is the Vanishing Point: 4.100+ over bores. Because all the guts of the LS-platform are on par with a typical SBC. I understand we are dreaming but somethings can become a reality if you could purchase a aftermarket block.