I have some heaers for a 350, but will they fit the LS1? They are SLP. What stuff will and won't fit on an LS1. Thanks.

 

Nothing you have now will fit it, unless maybe you have a generic wet nitrous kit.

 

Nope, they wont. a regular SBC has exhaust ports like this:

O OO O

An LS1 looks like this:

O O O O

 

I am currently doing an LS-1 swap and was wondering about headers as well. I am aware of the differences between the L98 and the LS1, but I am unsure of the dementions of the exhaust exits and bolt pattern. I am wondering..

L98 header flange
o oo o
1 23 4

LS1 Header flange
o o o o
1 2 3 4


L98 header on L98 flangeflange
o oo o
|| |||| ||
1 23 4

L98 headers adapted to LS1 flange
o o o o
|| \\// ||
1 23 4
/|\
|
note the center 2 tubes are modified

Pardon the crude interperatation.

wondering if the distance between holes 1 and 4 are the same on both the L98 and the LS1.. would it not work then to just change the header flange from an L98 flange to an LS1 flange (for bolt holes) and then modify the set of L98 headers to go into the LS1 flange?

if it were that simple it could be done from just about any exhaust shop if given the proper dimensions.

hopeuflly this can be done, I was hoping to adapt a set of hooker 2055's to an LS1 in this manner.

EDIT: spacing was all messed up on it. couldnt fix it but I think you get the picture.

 

The exhaust port heights are also different in relation to the crank centerline. IMO you are just opening up a can of worms that'll end up costing more in the end.

I dont think the length will work either. The SBC has ports on opposite ends of the head, the LS1 doesnt. One is on the end, the other is the space of 1/2 cylinder towards the center of the head. You could look at it like the first port lining up properly, and the rest will not.

 

You would be better off adapting LS1 headers to fit your installation. I stayed with stock exhaust manifolds. In fact the 01/02 mainfolds flow better than shorty headers.

 

I have kindof heard that the manifolds flow pretty well, especially compared to the L98 Log-style. I am not looking for 375hp YET <---- (operative word) so I'll probably just go with manifolds for now. were you able to leave the cats in on your conversion? or would those have to be moved? we do have emissions, and I may or may not need the cats to pass here.

 

doesnt help that the LS1 heads are 18* and TPI are 23*. I would try and see if MAC mid-length headers would fit, they are pretty decent, guys are deep into the 11's with em

 

There is no way anything from an L98 engine will fit the LS1.

You will have to buy all parts specific for the LS1.

 

LS1 heads are 15 degrees. Just one more aspect of their incredible performance capablilties!