I'm considering a Superchips for my '98 Expy 5.4 and maybe one for my '99 Flareside 4.6 but have a question about the regular chip, flip chip and required octane fuel.

First the flip-chip. I understand the reasoning behind the flip chip but wouldn't you be resetting the computer everytime you went from 87 to 92 octane? If it takes a few hundred miles for the computer to completely re-learn the program seems you wouldn't be getting benefit of the "power program" with just the flip of a switch. I use my Expy to tow but if I couldn't get an instant change with the flip is there any real benefit (other than shifting better) to considering the flip chip. What am I leaving out of the equation?

Now the regular chip. This would probably be the way I would go anyway but still wanted to ask. I think I understand the regular superchips reprograms the timing and fuel curve to optomize and increase HP. Do our engines have an internal knock sensor that retards timing when it senses pinging is present, even if we dont' hear it. If this is true, I can see where 92 octane is required to keep the program at it optimum program and prevent pinging or timing retard. So if you use 89 octane fuel instead of the 92, I suspect the internal knock sensor will retard the timing to close to stock settings. Isn't this acting like the flip chip then? Use 92 octane for performance and the lower octane for the lower setting. Also, will it damage the engine to run the lower octane fuel with a superchip or will you just loose performance. I'm sure I am oversimplifying the situation, but just wondering. Thanks.

 

Hi Greg

Your technical questions ill leave to the experts.

I use the superchip flipchip in my 99SC with 4.6L. 87/92oct. (87solo...92 towing) Other mods. cat back exhaust and K&N.

Shifting about same, my truck is very heavy, so any gains useing 87oct, i cant tell. What is noticable is when i switch to 92oct.

Your right, the new program is not instantly 100% maximum gains , but alot does come in right away and the rest gradually comes in. I felt the gains right away. Of course you really notice the difference, when after awhile you switch back to 87.

I dont commute or long haul daily anymore, so decided to run 92oct all the time. Actually picked up about .90mpg more, so...
Recent trip couldnt always get 92oct, only 91. I guess theres some lose of power, but i really couldnt tell, perhaps someone with a better sense of feel, etc, might notice. But, engine ran ok. No problems, mostly Chevron fuel. No drop in mpg. But now, oxygenated winter fuel here Oct 1 to Feb 1, so will loose alittle mpg and perhaps alittle hp. Chevron 87-$1.55gal 92-$1.75g.

Flip chip has some advantages, just have to pay more attention. I also tow and now realize 2 gas tanks with the flip chip would be alot better than one tank.

Good luck. OT
.

 

I was thinking the same thing, and decided to get the regular chip and run hi octane gas all the time. If I've got the performance available to me, I want it all the time.

If you think about it, the price difference is less than $5 per fillup, which does add up, but I easily waste $5 per week eating out or spending that extra cycle in the car wash (to make *sure* it's rinsed). I think that $5 extra per week is worth while if it makes my truck funner to drive.

As far as running 87 octane with the chip, I don't think I'll do it, but I've heard of others doing it with acceptable results.

I spoke to Mike T. yesterday when I ordered my chip. I asked about the 87-92 flip chip, he said the gains were minimal, like 5 hp with the 4.2L in the 87 mode. But gains aren't the only reason to get the chip. The flip chip will still provide better shifting in an automatic, as well as a modified rev limiter, and some other program benefits. I figured since I've got a manual transmission, I'd spend the extra $100 on a muffler to free up the exhaust.

Mitch

 

Hi Greg Mc,

There have been some excellent responses already to your basic question of how qquickly does the program change take effect with the Flip Chip, and as you can see, it happens very quickly. It's not 100% instantly of course, but when you flip the switch, you are in fact immediately changing the EEPROM chip and the program from which the ECU is getting it's instructions, and it goes to work pretty quickly. You're not waiting hundreds of miles to feel the effect.

It will take about 350-500 miles, and in 2001's a number of Key-on, Key-Off cycles to have the ECU fully implement 100%, but as long as the Superchip is installed properly, you're going to get 80% or so of what it will ultimately do very quickly, and then the last 20% or so will come in more gradually, as you accumulate the next few hundred miles.

Yes, these engines are equipped with knock sensors, *but*, the total effective compensation range varies, so anytime you run the Superchip, you need to use premium gas, 91 octane or higher. If you don't use the required good quality 91 or higher octane fuel, not only will you not get the power gain and driveability won't be what it should, but you also run the risk of detonation, as no knock sensor system is absolute, and their range varies quite a bit in these vehicles.

The only way you can safely use less than 91 octane gas with the Superchip is to use the 2-program Superchip Flip Chip, and have us set up one "side" of it for 87 octane, and the other being our normal performance program for premium gas. What we do is generally make both programs identical except for the octane the motor is tuned for, so you get all the other benefits no matter what, removal of full power delay, which automatics & manuals have alike, ts limiters, better shifitng in the automatics, etc. That's a popular & elegant solution for anyone who wants an optimized program for either octane level.

If you'd like to go over this in more detail, please feel free to give us a call, we're always happy to speak with you.

Best of luck with your trucks,