Thread: Gained 120+ RPM's!
10-23-2011, 02:16 AM #1
Gained 120+ RPM's!
I ALWAYS run a minimum of 98 octane fuel but decided to change fuel stations and gained a very noticeable difference! I used to swear by BP fuel but decided to try Shell Optimax, wondering if anyone else in Australia had similar results? I also used engine tuner that is a BRP product that de-carbonize your upper cylinder! Went from best of 8480 to 8620 .
10-23-2011, 02:53 AM #2
I only ever use BP ultimate or Optimax, can't say I've ever noticed one to be better than the other. But all the same, good stuff
10-23-2011, 05:12 AM #3
10-23-2011, 05:37 AM #4
10-23-2011, 09:12 AM #5
10-23-2011, 10:18 PM #6
10-24-2011, 02:05 AM #7
10-24-2011, 03:55 AM #8
Fill the top part in, for your specific location. Keep a small journal in you truck with what your max WOT rpm's were that day. You'll be amazed by the variances with weather.
-higher elevation, lower rpms.
-higher humidity, lower rpms.
-lower barametric pressure, lower rpms.
-higher temps, lower rpms.
Some folks talk about it in relative density. It's easier for me to remember using relative altitude.
10-24-2011, 04:31 AM #9
We call it density altitude (DA) and u can see 400-plus rpm change from one day to the next if we go from hot, sticky air to cold dry air such as a cold front having just moved in bringing high barometric pressure as well. A lot of testing results are off because this very important data is ignored during testing. Someone here sent a text my way last Wed to tell me we had great DA at the track that night. Around here we pray for #s like -2500ft or even lower (-3500 = lower)
Engine dyno computations account for DA, but your speeds on the water and times on the track do not.......
10-24-2011, 04:33 AM #10
2000ft for my normal riding area is a dream. I actually had a sub-500 day in the middle of winter one year when I hit a high, with a low temp, and nearly 10% humidity. Pretty sure I stuck a piston that day.
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