Guys we gave advice and he doesnt want to take our advice.

i think that if you can measure your rpm in the buggy then you have a good set up already. see what rpm you get at the end of the straight of just before a jump amd then try another engine to see if it reaches that same rpm or better.

also if your engine already is hitting 39,000 i think you need to regear some to better use the power of the engine. i would think most of these car engines ,ake thier best power in the 20,000-28,000 rpm range.

Good luck!