Strange, I have yet to actually dyno mine with the jet II with "good" gas,
but I can tell you that with the stage II I feel a difference between 87
and 93 octane. It just feels better with the 93+ than the 87. Also the
mileage is better with the 93+, I get high 17's mostly highway with the
93+, high 15's mostly city... like you mostly tire chirping fun... with the
87 I get 15.5 highway and low 14's high 13's mostly city ... I ahve tried
this a few times... for me it is worth the extra boost and the mileage
makes up for the cost difference... I never have any audible pinging
though. I do still have the 195 thermo.
Chris
>I decided to use 87 octane (Citgo) just to see if I could get this thing
>to ping. I've got a custom PCM with 5 degrees advanced timing. I'm also
>using a RS 180 tstat, but I'm blocking off the radiator for the winter to
>get the engine to run warmer (around 190-195). I just finished off a
>complete tank of 87 octane, under my normal driving habits, which are
>pretty hard driving! hee hee. My results were good, I did'nt notice any
>pinging, under any type of driving. Now, I must say you can't always
>"hear" pinging, so I can't say for certain there was none, but I never
>heard any.
>My gas mileage remained normal, 16 mpg mixed driving.
>I did'nt really notice any power decrease.
>For those of you concerned about upgrading your PCM and having to run
>premium gas in your 4.7L, I don't think you have anything to worry about.
>
>Matt Y2K-HEMI
>'00 RC 4.7L 5 spd
>14.23 @ 94.49
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'00 CC, Packin a 287 Magnum, 5-sp, Gibson Duals, Quick D Intake
http://www.intense99dak.com/chris.htm
In Action: http://www.dakota2.4mg.com/scca.htm
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This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 11:58:41 EDT