91 octane

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thinger2

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If the process of detonation and the role octane plays in preventing it is now clearer in your mind then the forum has succeeded (in sharing knowledge). Wouldn't have happened without your posts.
Thank you for that.
It has indeed helped me to understand a bit of an obscure subject
All of this is exactly why I joined this forum and recommend it whenever I get the chance.
This is a free education and has kept me off of the side of the road and off of tow trucks several times
 

L31MaxExpress

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Best thing a person can do is get some kind of scanner with advanced GM PIDs and monitor knock retard. If the PCM is retarding timing on 87 there is power and mileage to be gained with higher octane.

I like a ELM 327 device and OBD Link with GM Advanced upgrade.

This Bluetooth ELM327 device and a smart phone or tablet with OBD Link with GM Advanced update has not let me down. I also use it for my 8.1 99 Tahoe, my Nissan and Inifiniti. Downloaded the Nissan/Infiniti advanced stuff too. Can look at all the modules, read and clear codes, etc. This will let you adjust the Vortec distributor CMR as well without having to take it to a shop.

https://www.amazon.com/OBDLink-Blue...17a-1387-4dae-bb74-9da8fe434220&tag=cb-osp-20

Actually I don't even have to use a phone or tablet any longer. I have a 10" touch screen head unit in the Express that links directly to the Elm 327 device that stays plugged into the OBD2 port. I have a dash display built on the app that has a tach, long term fuel trims, commanded air/fuel ratio, knock retard, instant fuel economy, and trans temp. You can monitor practically anything in the OBD2 datastream. All have adjustable warning points. Hands free bluetooth calling and navigation maps.

http://vi.raptor.ebaydesc.com/ws/eB...4&pm=1&ds=0&t=1605833972000&ver=0&cspheader=1

My next additions are going to be the S10 steering wheel controls, backup camera, and tire pressure sensors.

For a tuner person that normally datalogs with HP Tuners its the coolest interior upgrade I have made to my 97 and it was less than $300.
 
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Frank Enstein

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Best thing a person can do is get some kind of scanner with advanced GM PIDs and monitor knock retard. If the PCM is retarding timing on 87 there is power and mileage to be gained with higher octane.

I like a ELM 327 device and OBD Link with GM Advanced upgrade.

This Bluetooth ELM327 device and a smart phone or tablet with OBD Link with GM Advanced update has not let me down. I also use it for my 8.1 99 Tahoe, my Nissan and Inifiniti. Downloaded the Nissan/Infiniti advanced stuff too. Can look at all the modules, read and clear codes, etc. This will let you adjust the Vortec distributor CMR as well without having to take it to a shop.

https://www.amazon.com/OBDLink-Blue...17a-1387-4dae-bb74-9da8fe434220&tag=cb-osp-20

Actually I don't even have to use a phone or tablet any longer. I have a 10" touch screen head unit in the Express that links directly to the Elm 327 device that stays plugged into the OBD2 port. I have a dash display built on the app that has a tach, long term fuel trims, commanded air/fuel ratio, knock retard, instant fuel economy, and trans temp. You can monitor practically anything in the OBD2 datastream. All have adjustable warning points. Hands free bluetooth calling and navigation maps.

http://vi.raptor.ebaydesc.com/ws/eB...4&pm=1&ds=0&t=1605833972000&ver=0&cspheader=1

My next additions are going to be the S10 steering wheel controls, backup camera, and tire pressure sensors.

For a tuner person that normally datalogs with HP Tuners its the coolest interior upgrade I have made to my 97 and it was less than $300.
That's sexy right there!
 

thegawd

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I forgot about this thread. Yeah the only reason I use the 91 top tier shell is because I can no longer find regular ethanol free fuel. thats all I will put in portable gas cans. Also my sierra has been a farm truck that has not left the farm in 5 years, it has not been to a gas pump and it sits more than it drives as its primary job was for hauling firewood.

well, I'm working on a 1956 Case 311 tractor so that it can do that job and I can finally finish building/restoring my sierra. I'm quite excited about that actually!

this old case tractor can run on all kinds of fuel from low grade 40 octane tractor fuel, (whatever that is) straight ethanol from a still to high octane aircraft fuels. however the carb needs to be absolutely tuned perfectly in order for it to vaporize the fuel and burn it at a proper rate.

this is why 91 octane has no benefits with our stock computer controlled trucks as they are tuned for regular 87 octane fuel.

what tricked me was how well the truck ran after starting to use the 91 octane fuel. the top tier fuel simply cleaned up the fuel system and it started to run very impressively.

I bought this truck off a buddy and he only buys the cheapest gas possible. Hell I'm the opposite and buy some of the most expensive fuels available and that being only top tier fuel from Shell. regular has 10% ethanol, 89 has 5% ethanol and 91 has no ethanol. this fuel is refined locally.

heres some shock value for gas prices! I went for the 91 octane for my tractor and damn near paid $6/gallon! that's the most I ever paid for fuel in my life!

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HotWheelsBurban

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Well it is the gold level lol.... around Houston it seems to be hovering between $3.00 to $3.25 per gallon. Y'all's price looks great until you see the "per litre" part. Yowtch!
 

thegawd

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Well it is the gold level lol.... around Houston it seems to be hovering between $3.00 to $3.25 per gallon. Y'all's price looks great until you see the "per litre" part. Yowtch!
hahahaha! Yeah I'm totally not doing the math on that conversion again today, I did it not long ago though and I'm sure it was a bit more than $6/gallon!

what's BS is where I live in Canada there are 3 major refineries and many multiple chemical processing plants that use up the leftovers. all of these plants are connected and help each other.

and Line 5 feeds all of them! shut down line 5 and destroy this economy.

anyways you would think that since this fuel is refined right here and us locals have to deal with the consequences of those chemical processes and the potential for really bad things to happen, we should get better fuel prices but we dont! not at all! man if one rocket landed in any given plant we would all be vaporized and a new great lake would be formed!
 

kennythewelder

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On the OE tune, it is set to run regular gas. To run any other gas is just a waste of money. Now if you have a tune, that's a different story. I had mine tuned to run premium, but it was starting to have some piston slap, so I reprogramed it to run mid grade, but I'm still running premium. I find that this works much better for me. My truck has more power and it gets better MPGs on the mid grade gas setting with premium gas. May have something to do with the fuel I'm running, the amount of ethanol in the gas, ECT,,,IDK.
 
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