I have a 421 HJR dune port serval with 33 pwks in my parts bin i was going to build up. I thinking of changing to a play port stock stroke stock cylinder and going back to stock carbs in an effort to get more seat time before fill ups. Question to the guys who have played around with engine set ups, how much more gas will be burnt with a 421 serval with 33s and CPIs vs ported stock stroke and 26s?