2006 Z06 LS7
As we all know the pump gas we have isnt all that great even with the prices of the 91 octane. Has anyone tried mixing some AV gas 105 with their 91 octance pump gas? I know that AV gas has lead in it.
Thanks

ThumperZ06

 

ive ran it on my c3 but its also got a carb. i wouldnt run it very much in a F.I. motor because for one prolonged use would probably destroy your injectors and possibly other parts of the fuel system also I dont think you would feel much of a boost in power, just get some chevron fuel system cleaner, it has xylene(sp?) in it and that will push your octane up a point or two. just my $.02

-alex

 

Using AV gas in any car with an O2 sensor is a really stupid thing. It ruins the sensor and clogs the cats. 100 Octane Low Lead really has a large amount of lead in it compared to even leaded auto gas. It is just lower lead content compared to 105 and 110 Av gas.

Don't be temped to do it, there are other ways (look up some threads on xylene or other additives) if your particular car is "octane hungry".

Improving octane isn't going to give you any more power unless you have a higher compression ratio, supercharger, or have a detonation problem where the knock sensor is cutting back the timing.

So, in short, not a good idea....

 

DO NOT DO IT.
Different stuff, different engine requirements.
BAD results.

Your Vette WILL NOT "take off".

 

Car is designed to run on 91, anything higher is just waisting $$$. Plus like others said you will mess up you converters and probably a lot more. Just not worth it.

 

Some race tracks (Infinion and Laguna Seca here in California) have fueling stations that offer 100 octane UNLEADED race fuel. Only minor problem ... price per gallon ... last I looked it was around $5.00 per gallon, and is probably above that now.

to learn more about Sunoco unleaded race fuel go to:

http://www.sunocoinc.com/site/Consum...UnleadedFuels/

and to find locations of Sunoco stations that sell 100 octane race fuels:

http://www.sunocoinc.com/site/Consum...T100Locations/

Union 76 used to have a site that allowed you to locate stations that also stocked unleaded racing fuel, but the link doesn't work anymore and their "new" site is a POS.

Try a Google, Ask, or Altavista search for 100 octane and the name of your state. You'll probably get several hits on places that sell unleaded 100 octane.

For those who claim it's "not worth it" ... well here in dear old No. Calif. the highest octane I can buy at the pump is 91, and the car is supposed to get 93 .... so when I go to the track I try and arrange to arrive with the fuel level in the tank at about 12 to 13 gallons. Filling the tank with 5 to 6 gallons of 100 octane gives me about a 93 to 94 octane tank (and yes you mix octanes to get a "new" octane ... the calculation is .... 12 gals * 91 octane = 1092 PLUS 6 gals * 100 octane = 600 (1092 + 600 = 1692) 1692 divided by 18 gals = 94 octane ......... VOILA !!!!

 

I have a small Cessna that was designed to fly on the old 80 octane AV gas...cant get it any more and the next step up was the 100 low lead av gas..seems the stuff has almost 4 times the lead that the 80 had...fouls plugs badly, damages valves etc...a lot of the smaller aircraft have gone over to car gas now..I have. I used to run the 100 LL in my 69 Roadrunner and had problems with lead fouling the plugs. There is an additive for 100LL that supposedly reduces the problem but for cars designed for unleaded I really dont see anything good coming out of burning it.

 

Just want to Thank you guys for your opinions and advice on the AV GAS. certainly dont want to take any chances with this new car. I am concerned about the CAI though. It just seems to be very restrictive to me and I know there are other owners like me that are thinking the same thing. Just needs to get more kool air.

ThumperZ06

 

I read all of the threads posted to this question and I agree completely with Z06inVB. I likewise have a Cessna and I run it on a mix of 87 octane auto fuel and 100 LL. The 100 LL fowls the plugs if I run it straight. I still like a little to provide lubrication to the valves and valve guides. I certainly would not recommend running that stuff in a Z06.

 

AV gas burns HOTTER then leaded race gas. I would NEVER recomend using AV gas in any car. Even at a higher octane rating your chances for detonation are increased. Unless you have higher compression then stock or your boosted or using N20 there is no reason to run anything above 93 octane. You will actually be SLOWER using race gas/av gas in a stock engine.

 

I had a Cessna Cardinal 177B when we would clean the plugs there would be little ***** of lead on the porcelain around the tip. I don't think this would be good for catalytic converters and o2 sensors.

 

Your math looks good but your information is not so good. Your stock 2001 engine is designed to run on 91 octane and I can't seem to find anything that says something like it's "supposed to get 93".

Charlie

 

There is no such thing, and never has been, 105 and 110 AV gas.

Karl
ATP CFI

 

I stand corrected, I was thinking of 115 (or so called "purple gas)...

Two ratings are applied to aviation gasolines (the lean mixture rating and the rich mixture rating) which results in a multiple numbering system e.g. Avgas 100/130 (in this case the lean mixture performance rating is 100 and the rich mixture rating is 130).

In the past, there were many different grades of aviation gasoline in general use e.g. 80/87, 91/96, 100/130,108/135 and 115/145. With decreasing demand these were rationalised down to one principle grade, Avgas 100/130. (To avoid confusion it is common practice to designate the grade by just the lean mixture performance, i.e. Avgas 100/130 becomes Avgas 100). Avgas 100/130 has both research and motor octane numbers slightly over 100, and is difficult to find. Avgas 100LL, the LL standing for "low lead" was introduced to allow one fuel to be used in engines originally designed for grades with lower lead contents. Avgas 100/130 is green in color, contains four grams of lead per gallon. Avgas 100 LL, is dyed blue in color, has two grams of lead per gallon. While 100LL is lower in lead compred to the older 100 octane fuel, anybody who has picked lead ***** from the bottom spark plug of a modern aircraft engine knows there is still a lot of lead in 100LL.

Avgas is less dense and has a lower specific gravity than most racing gasolines. Instead of weighing about 6.1 to 6.3 pounds per gallon like racing gasoline, it weighs 5.8 to 5.9 pounds per gallon, so you have a different mixture, that is it runs leaner than typical motor fuels if being metered by a carburator (hence the comment above that it burns "hotter' than auto fuels)...

 

SOOOO.... in a high compression 13:1 engine(654 hp/468ci) mechanical fuel injection. Would you be concerned runninf AV GAS, 100/130 as I have done on occasion when fuel was hard to find?
Very informative thread, Thanks

 

Charlie ... The manuals say 91, agreed, but several "racers" recommended running a slightly higher octane ... say 93 ... for track days to insure that:

1) I was not getting anywhere near a detonation (knock) situation at high revs and engine temperatures on track

2) The PCM was giving me as much advance on ignition timing as it would allow ... more power ... and ya gotta love that !!

Seeing as it costs several hundred dollars for a track day, I'll spend the "few" extra dollars on some 100 octane to up my "fun" factor

But for street driving, you're absolutely right, the engine is happy at 91 octane. I should have been clearer in my first post.

And to the IMSA dude asking about runniing AV gas in his monster (I'm green with envy over what that must sound and feel like !!!) take a look at :

http://www.sunocoinc.com/site/Consum...ditionalFuels/

To locate LEADED high octane fuels in your area.

 

Karl,
I routinely get my AV GAS ( written on the side of the truck) at my airport for my 1960 Vette. But It doesnt say 105 but the attendant tells me that it is near that level. Its clear and smells really sweet like it always has. It does make the 1960 with a 450 Hp SBC wind up at my elevation of 6000 ft. But my quesiton was related to the 2006 Z06 LS7 that I just recieved and was inquiring with the forum the pros an cons of using this in this paticular car. I am satisified that the question has been answered now to get the answer on getting CAI for this car that is currently breathing light air..
Thanks for your opinion.

ThumperZ06

 

I use a mixture of 100LL and the highest premium unleaded I can get around here in my 67' 400HP "427" Usually, I mix 6 gallons that I get while at the airport with a full tank of 92 Chevron. I makes a world of difference and runs much better without as much pinging.

While there are some experienced people here that claim their older Corvettes run just fine on today's gas, I seriously doubt it. Their timing must be way retarded. Even when my Corvette was brand new it wanted the very best pump gas, which is miles better than the poor gas sold today as unleaded premium.

There is NO substitute for real tetra-ethyl lead....too bad. You can't use AV gas in your new car because it will ruin your O2 sensors and catalytic converter, and it is also illegal in the new cars as well as old.

Best,

 

Your points are well taken and to a point I agree, however...
Personally, I think the best money spent would be to have the car professionally tuned for 91 octane. I run an I/C Magnuson and when the installation was complete, the car was specifically tuned to run on 93. When I drive out west I have to be very careful when all I can get is 91. The engine runs okay under "normal" conditions but doesn't like 91 one bit when I try to get a little "spirited". Using anything higher than 93 in my car is a complete waste of money. There is no advantage to running higher octane if the car is properly tuned for a lower octane. I'm going to look for an article that I recently read that demonstrates how running higher octane gas can actually reduce power in an engine that is properly tuned for a lower octane. If I can find it, I'll post a link.

Charlie

 

Charlie,

That would be great. Hopefully it addresses issues like open versus closed loop fuel management. For the track, since you are often WOT, the PCM is in open loop mode, and I really want to understand better what if anything I can do to improve engine performance in that area. I totally agree that running higher octane than the engine is "tuned" for is a waste of money. I just try to get the octane a couple of points above 91 as a more-or-less "insurance" policy for those days I am really hammering the engine.

Thanks for your posts,

Steve