Hi there, I own a 1996 Chevy S-10 SS with many hi-performance mods including Hypertech Power Programming. My truck has the Pushrod 4.3 Vortech V-6. I have a desperate need for High Octane Fuel! My programming requires the use of 93 Octane Fuel or the highest in my area to achieve the full performance benefits of the programming, but I live in Albuquerque, New Mexico where the only high octane fuel we have is 101 Trick Racing Fuel! I do not have convenient access to it due to my work schedule because the one gas station that sels it is only open from 8 A.M. to 5 P.M. Monday-Friday, and it costs $4.25 a gallon! This gas station also is in our downtown business area and is not convient to where I live and work! So I have been using 91 Octane with an Octane Booster in hopes of achieving 93 Octane, but it just does not seem to be working.

      I wish that there were gas stations that Sold 93 Octane and other high grade fuels where all I have to do is pay at the pump whenever I need to fill up! I have been trying to e-mail Conoo-Phillips about building Unacol 76 Gas Stations in my city because they sell the high octane fuels I need and desire! They e-mailed me back saying that I do not need higher than 91 octane since I am at a higher elevation. It doesn't matter if I don't need it or not, but I wan't it anyway so that I can be on the safe side! I also e-mailed Sunoco Inc. about building there gas staions in my town since they too sell the high grade fuels that my truck requires and desires! I have yet to hear from them. I am desperate!!!! If anyone can help me make this issue an extremely important one so that these gas companies will build these gas stations in my city I would sincerely appreciate it!!!! THE NEED FOR THESE HIGH OCTANE FUELS IN MY CITY IS GREAT!!!! Please help me to somehow get these companies to listen to my cries for High Octane fuels in my city!!!! Thanks!!!!

Sounds like you've got a design problem. If you need 93 octane and can't get 93 octane, I'll wager you'll need to calm the engine way before Sunoco or anybody else delivers 93 octane to you.

Albuquerque is pretty high, in terms of atmospheric air pressure, an engine's octane requirement goes down with altitude simply because at the lower air pressures it can't fill itself to a point where the real compression is anywhere near the calculated mechanical ratio. However, that being said living in the mountains does put higher cooling loads on the engine since its working harder both because of the altitude and because you've got to deal with grades that require the use of more throttle. So it's possible that the end burn temps will take the engine back to the detonation/preignition zone.

The 4.3 with injection has a detonation sensor that will protect the engine in the event that you encounter detonation/preignition by retarding the spark. You'll know it when this happens as the power just suddenly goes away.

I suspect your choices are to change the chip to something more custom (I'm guessing you bought a JET chip or something like that over the counter) these probably won't optimize the engine for your altitute.

Try these people for a custom chip:

http://www.fastchip.com/

http://www.hypertech-inc.com/

http://www.superchips.com/

http://www.kcspeed.com/

Aluminum heads are typically good for a point of compression more for a given grade of fuel because they pull combustion heat out faster than castiron. In your case they could be used to optimize compression around your chip's characteristics and still get by with 91 octane.

Bogie

      Hi there, oldBogie! Thanks for the reply! I had mentioned in my post that I am currently using Hypertech Power Programming. For my model year Hypertech does not offer a chip, but only the Power Programer 3. In their manual that came with the programer, it specifically states that because the programer increases the engine spark, I'm required to use 93 octane or the highest in my area! I looked at their website and found dyno results showing the difference in octane ratings with this tuning. These results show that if I use 93 Octane gas, then I will achieve the full power bennefits of the tuning, but if I use 91 Octane then I will only see maybee 80%-85% of the power bennefits. This is my dilema! I want to achieve the MAXIMUM POWER bennefits of the tuning, but according to Hypertech, I can't wihout 93 Octane gasoline! I also CAN TESTIFY that the 101 Octane racing fuel that I mentioned in my post makes my truck send me a love letter because it runs so much better than it ever could with 91 Octane! What I mean is that when I run this fuel, I notice an increase in performance and power right of the bat! And it aint' NO joke!

      So I guess my real question is why can I get 101 Octane racing fuel, but I can't get 93-99 Octane gasolines at this altitude, and If I am seeing greater benefits with the racing fuel over the 91 Octane, than what gives?? Why would I be seeing these benefits?? Can you maybee explain this to me 'cause I'm getting very confused and frustrated?? Any other help on this matter would be much appreciated. Thanks again for the help!

If your really having measureable improvements with 101 octane, it's telling you that the engine is in preignition or detonation, whether auidible or not. The improvement then is increased power through a smooth burn.

An old fashion trick is water or water alcohol injection. First developed for high performance piston aircraft engines, a little shot of water or water alcohol pulls the end-burn temps that cause detonation down below the explosion point. This lets you pull more power as if the octane rating of the fuel was higher. They did it to get around lead fouling of the spark plugs, which goes nuts with 120-140 octane leaded fuels and became impossible, even with bromine doping, at 150-170 octane, so those nearly solid lead fuels never made it out of the lab.

I haven't seen water injection kits for sale for sometime but also haven't looked so perhaps JC Whitney still sells them. They work off air flow demand and would come on as manifold pressure drops toward atmospheric as the throttle reaches full open. If your running a blower, the system would need to be modified to function as manifold pressure exceeds atmospheric. So in its simplest form this just becomes a diaphram controlled valve at the extrme edge of modern computerized systems I guess this could be programmed into a "Power Programmer" type pre/post-processor.

Bogie