Sunburst-Kid

My goal is to maximize my daily driving HP & Torque, so I'm going with the 93 Performance tune. I never, ever put 87 octane in anything, not even my lawnmower. For me, regular gas means 89 octane. Around here in NC, each grade goes up about $0.12 per gallon (gone are the days of $0.10 increase per grade ). Some stations charge $0.14 for 93 over the price of 89. Do I hate paying 14 cents a gallon more just to run 93 octane, of course I hate it, but at the same time I just do the math. Even at 14 cent increase over 89 octane, and assuming a "sitting on empty" fill-up of (say) 19.5 gallons, well that's an "out-of-pocket" increase of just $2.73 per tank. Ok, so I drink one less draft beer that day and I recoup my losses. If we use JPop's example of 20 cents more for premium, then were are looking at $3.90 per tank. Ok, so that's either 2 good beers or maybe a six-pack of crap beer. Either way, we are talking about less than $4.00 per tank. I don't have money just lying around, but come on, $4.00 a tank. Just do like some of us do: swipe card, select grade, lift handle, fill-up, replace handle, press "NO" when asked "do you want a receipt", don't look back.

JPop

Higher Octane fuel isn't any better than regular it just burns slower. Higher Octane doesn't contain more power, it just allows the timing to be more advanced and in the case of many engines less timing retard because of the knock sensors.

With any engine there are physical and mechanical constraints as to how much octane they will support. Then there are the PCM issues which programmers can somewhat deal with but they are still confined by the physical limitations. So despite there being ways to address timing advance, PCM and knock sensors higher octane fuels can still have diminishing returns even if used with a very robust programmer.

Crazyboattower

Does the superchip allow for changing tire sizes?

BadTime

Yes it does.

Calypso

None do what the SC does! Plus, if SC comes out with some new options, all you have to do to get them is plug in and download!

Sunburst-Kid

Hey JPOP, even though we only have a compression ratio of 9.6:1 in our 3.8's, don't you think Superchips has done a bit of homework in their tinkering with the Flashpaq to be able to offer a 93 Performance tune? I know higher octane doesn't directly mean more power and that it does allow for a higher timing advancement due to a slower burn rate. That said, isn't it still advantageous to obtain higher advance and thus the need to run higher octane to control "knock" at these higher advance levels? My guess is that they can take more advantage during WOT conditions and really advance the timing. Maybe not.

Also in my case, the only octanes around here are 87, 89, & 93. So Flashpaq wise, the only two options would be either the 87 tune or the 93 tune; I'm going with the 93 tune.

Jmacaws

I got superchipped today

JPop

I know that Superchips does a great job with their tunes. I'm also sure from my own tests with the 93 Octane setting there is more power than with 87 Octane. That said, from stock to a Superchips tune I am probably realizing 80% of the efficiency gains with 87 Octane. So for me the whole equation becomes cost/value and I'm not really sure I see enough value in going to 93 Octane to spend an extra $5-6 a tankful.

As I've mentioned before, the higher gas prices are the smaller the percentage of a bump in price to run premium is. I haven't had a good opportunity to run an
87 to 93 tankful comparison. What the current prices at the pump tell me is that there is a 9% additional cost to go from 87 Octane ($2.19) to 94 Octane ($2.39, what I run with the 93 tune). So for the additional power increase I get, I also want to see at least half that in an efficiency gain or mpg. Flash back to last summer with regular running $3.79 per gallon and premium at $3.99, the difference I needed to see in performance/efficiency was just 5%, and half that isn't to difficult to achieve.

My Hemi Ram and Superchips is a totally different story than the JK. I see huge gains from running premium as compared with lower octanes. I'm certainly not an engineer, but there are lots of mechanical differences such as 2 plugs per cylinder which promote better fuel burn and enables more advance along with a host of other differences. Going from regular to premium I see a 15% gain in mpg efficiency so gas prices would need to fall to the sub $1.50 range before I would consider running regular.

While I am very much performance minded with a 67 Chevelle in the garage and also a '79 race Malibu in the garage, this jeep and truck is what I drive everyday to get where I'm going. I don't need to smoke the tires from every light but I still enjoy having additional performance, but I won't suffice great deals of efficiency to go there.

I know that was a little long winded but I hope it clarifies what I said in my previous post. We all don't have the same cost/performance goals in mind so for some the 93 octane tune is worth it for their jeep. For me, I'll wait until the gas prices climb a bit or I have some off road plans where I think I would enjoy the performance bump.