Lm7 cathedral port heads vs. Ls1 rectangular manifold
#1
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Help,
I am putting together a project vehicle that i have the opportunity to buy a brand new lm7 long block for 1200.00 and the heads have the cathedral ports. The issue here is I have a 2001 ls1 corvette Intake Manifold that i want to use with rectangular ports. Will they mate together, do I have to change heads, is there a special adapter that I can buy????? Any input will help!!
I am putting together a project vehicle that i have the opportunity to buy a brand new lm7 long block for 1200.00 and the heads have the cathedral ports. The issue here is I have a 2001 ls1 corvette Intake Manifold that i want to use with rectangular ports. Will they mate together, do I have to change heads, is there a special adapter that I can buy????? Any input will help!!
Last edited by IAMC4CRAZY; 10-04-2011 at 02:11 PM. Reason: misspellings
#5
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Now i am definately confused! From what i have read all ls1 motors, including in Corvettes up to 2001 had cathedral port heads, but the intakes all have the Rectangular ports. "NVR SPDS" says they will match up and now "pairof69s" says they won't! I value all you guys inputs, but i need definate clarification here!
#6
TECH Addict
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The LS1/2/6, LM7, LQ4/9 (i know im forgetting some others) are all cathedral port heads, the intake itself is NOT cathedral in shape, it actually is rectangular in shape, so all these bolt up to the cathedral ports. Just as the LS1 came with the LS6 manifold.
The LS3/L99 head ports are rectangular, but they are a shorter, wider port design. The LS7 IIRC is also a rectangular port, but with a design, and port spacing all its own.
Ill see if i can dig up the thread showing the differences.
The LS3/L99 head ports are rectangular, but they are a shorter, wider port design. The LS7 IIRC is also a rectangular port, but with a design, and port spacing all its own.
Ill see if i can dig up the thread showing the differences.
#7
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Thanks fellow ls'ers! I really appreciate the imput! Hey "NVR SPDS", I am assuming that you have now clarified that these are a match, but i am still looking forward to that thread you spoke of!
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#10
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So not to butt in, but I just purchased a LS-6 intake for my 5.3 I'm building, when I received it the intake has what looks like rectangle ports and my 5.3 heads have the cathederal ports, can I use this intake, do the LS-6 intake come with either rectangle or cathederal ports? very confused at this point if I can use this intake or not.
All replies are appreciated.
All replies are appreciated.
#11
Super Hulk Smash
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Everything prior to the LS3 used a cathedral port head design, whether Gen III or Gen IV, truck or car.
Gen IV LS3/L76 changed to the rectangle port design. LS7 is a raised rectangle port.
And when we talk about port design, we mean the heads.
The manifolds are all rectangle in shape, but will not mate up to another head port design... i.e., LS1 and LS3 are not interchangeable.
So as long as the intake you bought is LS1,2,6 or the LQ9/4 or LM7, L33 truck intakes, they will all work on any cathedral port head.
Gen IV LS3/L76 changed to the rectangle port design. LS7 is a raised rectangle port.
And when we talk about port design, we mean the heads.
The manifolds are all rectangle in shape, but will not mate up to another head port design... i.e., LS1 and LS3 are not interchangeable.
So as long as the intake you bought is LS1,2,6 or the LQ9/4 or LM7, L33 truck intakes, they will all work on any cathedral port head.
#12
TECH Junkie
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when I received it the intake has what looks like rectangle ports
The real "rectangular" ports that you hear of from the LS3s are completely different.