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Author Topic:   fuel whats works
fastride
Member
posted September 06, 2003 04:30 PM
Dirtbandit is right about the amount of octane. You only need enough to prevent premature ignition. How much is enough? Read your plugs with a good magnifing glass and look for tiny shiney blue/black balls. If you see them you need more octane. This is a simplified course, books have been written on this.

Now the problem. Pump gas is seldom the same from load to load, season to season. It has as much as 5% refinery byproducts. These are always of lower octane values. Av gas is more consistent but has a vaporization point for higher altitudes. Therefore it doesn't vaporize at race track altitudes as well. Race gas is consistent. It is also more expensive. Often it is of a higher octane than needed in a street stock. Although not perfect, a blend of race gas and pump gas might be about right. Remember, excess octane is slightly detrimental to power and the wallet.
SLEEPY


rico 08
Member
posted September 07, 2003 08:49 AM
Sleepy's right(as always),the only thing i'd add is don't run it until you see shiny balls on the plugs,it doesn't take long to destroy an engine during detonation in racing conditions.Use straight pump gas only in an engine with compression below 9.5,and even thn be careful,i've seen pump gas ruin more engines than almost anything else.Sleepy i noticed in STOCK CAR RACING Mr jull putting down your welding/fabricating work,personally i think it's the most real life example of how real everyday racer's work will be like and turnout,not something off of monster garage or nascar garage with 75k salaried master welders with 10k machines doing work that only a few people can duplicate.I absolutely love passing these guys on the track,it's priceless.Keep up the good real world work.


fastride
Member
posted September 07, 2003 03:49 PM
1/3 115 octane turbo blue
2/3 93 pump gas

Come out to right about 100 octane and the lead from the TB helps stop detonation a bit more too. Around here, 115 TB is $4.25/gal and 93 is around $1.90/gal. So the mix comes out to be about $2.70/gal. Can't complain much about that. I just bought a 30 gal plastic drum that I take to the station that has TB in there pumps about once a month and I'm good to go.

** edit **

Ohh.. 10.5:1 street stock, 461 heads, flat tops, AR72 plugs, 35-36 degrees timing and 6000-6200 rpm.

[This message has been edited by Raz_900 (edited September 08, 2003).]

fastride
Member
posted September 08, 2003 07:50 PM
Hi Rico08, Many thanks for the kind words. Yeah, even though now at Stock Car Racing I have the opportunities to use bucks up parts and pieces I try to keep it the way I have always done: build what I can and buy what I have to and pass along as much as possible of what I have learned.
SLEEPY


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