Can the stock 5.3 hardened intake valve seat insert be used to run the larger 2.00 valve from the 5.7 LS1? I realize it would have to be cut for a larger seat; or do you have to replace with the LS1 seat?

 

No you don't have to change the seats. Just do a valve job for the new valves. There is much material to be removed and with out any port work or chamber work you will have a worse flowing head than the 5.7. So consider yourself informed. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

<small>[ March 19, 2003, 01:15 AM: Message edited by: 2000RATA ]</small>

 

Thanks 2000RATA, I do plan on porting. You say a worse flowing head? I assume you mean on the intake side only. I thought that stock, the exhaust side of a 5.3 outflowed the 5.7; I will check that on the SuperFlo.

 

For once, I'd like to see the same person (or shop) do head flows on stock, unported 5.3, 5.7, LS6, and 6.0 heads and post the numbers. Same equipment, same settings, and same day would be nice. Above and beyond that, I think it would be nice to see how those stock heads responded to a valve job only, and with the 5.3, a 2" intake valve.

 

BigTex,

I'll do that when I get the LS6 heads here in a week or two. I have all the others. I might even do all of them with the different intakes, LS1, 6.0, & LS6....now that would be a cool test.

 

Scott - Thanks for stepping up on this. It will be very nice to see this info in one place done by the same person at the same time.