MrHP,

so your saying I will have better performance using 87 over 91 in my Stage 1??

And it's just as good for the engine, etc?

 

The lower octane you can run without pinging the better. High octane fuel is more of a bandaid than a performance enhancer. It stops detonation and has to be used on high compression engines, thats why high octane is associated with high performance.

When cooler weather comes you should go with a little higher octane because with cool weather comes low humidity. High humidity actually cools the combustion charge with its water vapor and slows down the burn rate, thats why you go to low octane(quick exploding) fuel in the heat of summer.


MrHorsepower

 

higher octane = less heat. run the 87 and run hotter - whether or not its enough added heat to hurt anything will remain a debate.

the raptor and ds both use the same bsr carbs, and many other sources have shown a dyno proven increase in hp on both these bikes from lid removal when properly jetted. But MisterHP is also not the only one to claim the opposite. Personally I don't know which way to lean, I always ran lidfree with stock carb, because I added a pipe, CDI, and pulled the lid all the same time and never really tried to see an actual difference in drag results. If I still ran stock carb, I would try both and see which one got the best results.

 

When I first saw MisterHP run at the ATPT summer nationals, I couldn't believe how fast his bike was running. I ran him several times the day before the races and he blew my basically stock machine away time after time. At the time I was running a carb mount k&n on the stock carb with 93 octane fuel. When I asked him what fuel he was running I couldn't believe it at first, but now I'm a believer! I saw him knock off machine after machine with his setup,stock and modified alike! BTW, on actual race day, he won the stock class 300 and 660 ft trophies. There is video of these races floating around as well. I can't wait to try out my new lectron 46HV tuned by MisterHP!
[img]i/expressions/face-icon-small-smile.gif[/img]

 

buttfungus, if ya dont mind me askin how much was it to go to the lectron?

 

send me an email and I will give you all the details[img]i/expressions/face-icon-small-smile.gif[/img]

my email

 

WOW thanks for all the usefull info mrhp. It definetly answered all my questions about the spring, and i learnes a few other cheap mods.

 

its on its way buttfungus

 

lilnotts
Cool, I sent you a reply.....

 

Hey MisterHP you might like this one.Back in the 70's I worked with a guy named Dale Funk. Dale drove the Frakes & Funk AA gas dragster.For a while he held the IHRA record. He explained to me how his car had to run regular because at the RPM they were turning, higher octane fuel was still burning on it's way out the exhaust. Apparently detonation wasn't a problem,anything to get the charge burnt I guess.