So I finished up with all the mods that you can do for NA, CAI,Headers,Catback. Just pulled the stock bin file and I'm about to go over it. Noticed that the dam thing is really lazy on timing, that's gonna change. Anyways I have a set of 6.0L heads I pulled from a Goat that I swapped for a set of AFR 225's and was wondering what heads are on the 5.3? I noticed the casting number #243 on top of the head of the 6.0L heads and the same casting number is present on the 5.3's. Are they the same head? Trying to find any info about this stuff is a pain, to new I guess.

 

Which headers did you go with?

 

JBA. According to some info I gathered our engines the LMG we do use 243 casts but the cc is 61 and the intake/exhaust port volume in cc is 200/70 compared to a 65 cc and 210/75 that the vette uses.Maybe just a quick .020 off the heads will bring her to 58cc and get me closer to a 10.0:1 comp ratio than the 9.49:1 that we have now. Bigger valves bigger port volume = more power and maybe better mpg.