Is this an LS6 intake?
Originally Posted by Ole1830
I might be wrong, but I believe all you'll need will be a LS6 intake coolant bypass kit, available from GM. It costs around $40. 
Originally Posted by CharlieLed
Here are some numbers that I have gathered:
LS6: 12573572; 88894339; 88890523; 12561184
LS1: 12560688; 12556333;
Endres book calls out P/N 12561182 for 2001-2002 LS1 but since I haven't actually seen one of these manifolds I can't say one way or the other whether it is a large runner (LS6) model or not.
SlowZ28...if the manifold that you installed was an LS6-style then you would have had to replace the coolant lines that run under the LS1-style manifold. If you look at the photo of the two manifolds you will see that the one on the left, the LS1 unit, has the marks in the brown foam from the coolant lines. The LS6 model does not allow enough space for these lines and therefore must have the rear water outlets/crossovers in the heads blocked off...only the front outlets are used.
LS6: 12573572; 88894339; 88890523; 12561184
LS1: 12560688; 12556333;
Endres book calls out P/N 12561182 for 2001-2002 LS1 but since I haven't actually seen one of these manifolds I can't say one way or the other whether it is a large runner (LS6) model or not.
SlowZ28...if the manifold that you installed was an LS6-style then you would have had to replace the coolant lines that run under the LS1-style manifold. If you look at the photo of the two manifolds you will see that the one on the left, the LS1 unit, has the marks in the brown foam from the coolant lines. The LS6 model does not allow enough space for these lines and therefore must have the rear water outlets/crossovers in the heads blocked off...only the front outlets are used.
Where did you find those numbers?I have a Christopher P Endres LS1/LS6 performance book, and i dont see the 12561184 number outta GM.All I see is the 12561182 number. Any help?
Staging Lane
Joined: Jun 2004
Posts: 85
Likes: 0
From: Amarillo,TX
Easiest way to tell if its an LS6 or not is look at the intake right after the throttle body. There will be kind of a square looking area and if it has a hole and a screw boss in it its an LS1 intake because they have the EGR provision right there........If its an LS6 it will be blank in that little square area. All you need to do for the coolant passages is plug the rear two and only use the front crossover either by cutting your old one or buying an LS6 one.
TECH Fanatic
Joined: Aug 2004
Posts: 1,373
Likes: 4
From: Auckland, Nth Is, New Zealand.
Originally Posted by M6WS6
Where did you find those numbers?I have a Christopher P Endres LS1/LS6 performance book, and i dont see the 12561184 number outta GM.All I see is the 12561182 number. Any help?
