435 HP running on pump gas

[Joe L.]

Re: 435 HP running on pump gas

You have to know if the octane rating is RON, MON, or PON which is the arithmetic average of RON and MON, and the difference is typically in the range of 8-10. "Race gas" can use any of the above methods, so you have to do some homework to find out what you have. The dealer will probably though out some "octane number" but hasn't got the foggiest idea what it really means. Get a spec sheet from the fuel blender.

Avgas uses a different method, but it's close enough to MON to assume that.

Once you have appropriate estimates and converted everything to a single rating system of you choice you can use linear interpolation to get a good idea of what octane rating a blend has.

If that's not a good enough estmate for yourself, you can hire a test lab to test whatever blend you want to submit.

The trouble with the above is that few really know what minimum octane their engine needs, and because of octane sensitivity to things like inlet air temperature (less on a cool winter day on the highway than on a hot summer day in traffic) it often boils down to a matter of experimentation.

Start with a minimum amount of a high octane blend in pump premium, like 10 to 20 percent and keep increasing it until there is no detonation under worse case condtions. Whatever the octane number of the blend is what the engine needs.

Duke

Duke-----


In today's world virtually all the fuel sold for AUTOMOTIVE PURPOSES is rated by the PON (i.e. R+ M/2). I believe that one is assured of this if the fuel is labeled with a "squarish" emblem with yellow background and large black numbers (representing the PON number).

I believe all fuel sold in traditional service stations must be so-identified
under federal law. Also, "Rocket" brand racing fuel (the successor to Union 76 racing fuel and the most widely available, if not only available, high octane fuel on the market) also uses the above-referenced octane-identifying labels.

As you mention, aviation fuel is rated using another system. However, aviation fuel is illegal to use for automotive purposes under state and local laws and, for regularly driven cars, is completely impractical notwithstanding the legalities.

[Rick M.]

Re: 435 HP running on pump gas

Thanks Joe,
That's my thinking as well, I'm going to check various websites beginning with summit. The race fuel issue gets old (storing it etc.) and hauling the drums around isn't any fun either.
As always, appeciate the advice.
Rick

[Duke W.]

Re: 435 HP running on pump gas

Duke-----


In today's world virtually all the fuel sold for AUTOMOTIVE PURPOSES is rated by the PON (i.e. R+ M/2). I believe that one is assured of this if the fuel is labeled with a "squarish" emblem with yellow background and large black numbers (representing the PON number).

I believe all fuel sold in traditional service stations must be so-identified
under federal law. Also, "Rocket" brand racing fuel (the successor to Union 76 racing fuel and the most widely available, if not only available, high octane fuel on the market) also uses the above-referenced octane-identifying labels.

As you mention, aviation fuel is rated using another system. However, aviation fuel is illegal to use for automotive purposes under state and local laws and, for regularly driven cars, is completely impractical notwithstanding the legalities.

All commercial fuel sold for road use has to carry a PON rating, but I have seen some "racing fuels" where the type of rating used was not at all clear, which is why I recommend all seek out a detailed spec sheet for any "racing fuel" that they buy.

Duke

[Dale S.]

Re: 435 HP running on pump gas

Joe, Rocket is more popular on the west coast. V.P. is a much larger company and Sunoco seems to be stronger in the east. All of them make about the same product quality wise. Last summer I saw a pump in a Sunoco station in Colombus Oh., that was selling racing gas from a pump. I had never seen that. It assume it was the Non leaded Sunoco racing gas. We have seen the quality of fuels go down over the years and I think it will get worse. The days of Chevron white pump, Martin purple, Sunoco 260 (100-101 octanes) etc. are gone. There are many other companys selling racing gas. You can get a list of racing gases on NHRA. com If anyone wants I have the list here also a the house( email me) Dale

[Joe L.]

Re: 435 HP running on pump gas

Joe, Rocket is more popular on the west coast. V.P. is a much larger company and Sunoco seems to be stronger in the east. All of them make about the same product quality wise. Last summer I saw a pump in a Sunoco station in Colombus Oh., that was selling racing gas from a pump. I had never seen that. It assume it was the Non leaded Sunoco racing gas. We have seen the quality of fuels go down over the years and I think it will get worse. The days of Chevron white pump, Martin purple, Sunoco 260 (100-101 octanes) etc. are gone. There are many other companys selling racing gas. You can get a list of racing gases on NHRA. com If anyone wants I have the list here also a the house( email me) Dale

Dale-----


I had no idea that there were that many different racing fuels available in today's world. I guess I've been away from any involvement in racing for a LONG time now. Actually, that happened well before Fremont Dragstrip closed and that's been a long time ago, itself.

I found the attached chart which shows cross references for most of the major brands and formulations. It also shows the motor (MON), research (RON), and R+M/2 (PON) octane ratings for all the brands and formulations.

Personally, for street purposes, I would not even consider owning a car that required ANY of these special racing fuels. Even if I drove the car only a modest amount I still would not want to be held "hostage" to fueling only from a drum or fuel can.

http://www.whitfieldoil.com/downloads/SUNOCORACINGFUELCROSSREFERENCECHART.pdf

[Dale S.]

Re: 435 HP running on pump gas

Joe, I used to save the fuel samples from national events and run it in my 67. the mixure of racing gases really made it run good. BUT you should have seen the stuff in the bottom of the tank. Tim Wuzu who worked for 76 racing( now one of the owners of Rocket racing fuels) told me part of what was clogging up things up was the ferrousine(sic) ( Iron) was persipatating out of the fuel. the fuel was yellow at that time and when setting in the sunshine it looked like rust on the bottom after a half hour. He said the ferrousine slowed spark detenation. Dale

[Dale S.]

Re: 435 HP running on pump gas

Joe, The last count I had on racing fuel brand names there were 24. Each gas must be sent to NHRA so we can check it before the season starts. Then it will be on the excepted list for the season. This is costly and only about 10 do it each year. Then it's graph chart on the G.C. must match the racers gas sample at the races. They give a sample after every round. Dale

[Rick M.]

Re: 435 HP running on pump gas

Dale,
I'd like a copy of the list you spoke of if it includes dealer network info. Having said that after going through the buying race fuel for a street car scenario I completely agree with Joe. The fuel hassle takes a lot away from the fun.
Thanks,
Rick

[Joe L.]

Re: 435 HP running on pump gas

Dale,
I'd like a copy of the list you spoke of if it includes dealer network info. Having said that after going through the buying race fuel for a street car scenario I completely agree with Joe. The fuel hassle takes a lot away from the fun.
Thanks,
Rick

Rick-----


It also essentially restricts operation of the car to an area within 1 fuel tank's range, roundtrip, of your home since it's impractical to fuel "on the road" if you require racing fuel. Road trips, in my opinion one of the great joys of owning a Corvette, become totally impractical. It's ok for folks that have a bad case of agoraphobia, though.