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Juiced06GTO · 07-19-2010, 03:16 PM

Older vette heads (97-04) (cathedral ports) will work on the smaller bore. I believe there is even a company making l92 style heads that will fit the smaller bore of the original ls1's, but the bore on the 5.3 is just to small to accomadate the valves in the l92 heads. This is not really a huge problem as there are a ton of heads that will fit that flow great and will make a ton of power.

Your best bet from a cost stand point would be to pick up some 243 casting number heads, get them cleaned up, and slap them on there. As for a cam, something in the 224-228 range on intake and exhaust with around .550 lift would probably work pretty well. My GTO runs a 232/234 with .598 lift on i/e but with the bigger displacement 6.0. With only 5.3L I would stay smaller to keep it driveable and easily tuneable.

07-19-2010, 03:16 PM	#16
Juiced06GTO Registered User Join Date: Jul 2010 Location: Sutton, MA Posts: 130	Re: In the spirit of the new forum I have LS swap questions. Older vette heads (97-04) (cathedral ports) will work on the smaller bore. I believe there is even a company making l92 style heads that will fit the smaller bore of the original ls1's, but the bore on the 5.3 is just to small to accomadate the valves in the l92 heads. This is not really a huge problem as there are a ton of heads that will fit that flow great and will make a ton of power. Your best bet from a cost stand point would be to pick up some 243 casting number heads, get them cleaned up, and slap them on there. As for a cam, something in the 224-228 range on intake and exhaust with around .550 lift would probably work pretty well. My GTO runs a 232/234 with .598 lift on i/e but with the bigger displacement 6.0. With only 5.3L I would stay smaller to keep it driveable and easily tuneable.