So in my regal I been spraying a 200 shot on my 400 sbc almost all summer probably 25-30 bottles on 93 pump gas,I hit it with a 250 for the heck of it and felt slower this was on race fuel ,I tryed this with 28* and 30* just didn't feel like a hard hit like the 200 on pump gas and 30* debating on hitting it with 250 on pump gas plate only goes to 300 been searching on other forums can't find right answer,plugs are NGK #8s ,200 all at once out the hole with manual trans 90% street car