Racing fuels

[Dave Cofone]

Since I am unable to get gas without some percentage of alcohol in it I will have to buy my gas from the airport or a racing fuels distributor. What do you all use in your Yamato engines to keep the temperature down and lubrication up.....?

[M Miner]

I used VP MS 93 with my 302. And did so because Cliff told me to.

[John Korbus]

do you have smart phone use app
Pure Gas
will show stations around that has alcohol free fuel. use on the way to races will direct to stations.

[3rd Chance]

Unfortunately for Dave (and me) he lives in NJ, where there are ZERO gas stations that sell ethanol free fuel. Best bet is VP or Powermist fuels.

[ZUL8TR]

Maybe a racer coming to the race from an area where they sell E free can bring you 4 gallons?

[ricochet112]

do you have smart phone use app
Pure Gas
will show stations around that has alcohol free fuel. use on the way to races will direct to stations.

NJ does have have non corn gas

[John Korbus]

pure-gas.org New Jersy shows 12 area to find fuel some airports also gas stations and a Morris County Marine

[Matt Dagostino]

John............those stations are mostly VP Fuel distributors or sell AV gas. I think the goal is to find PUMP Non- Ethanol free gas like we have here in Maryland-Virginia. My local non-ethanol free gas station has 87 octane for 2.79 a gallon last time i bought it. Heck, now and then i treat my truck to a tank! I love the tee-shirts you have. Our Balls Products continue to work great. Hope all is well.....

[DeanFHobart]

Also for ethanol free gas try a farm equipment store or a grange store.... also try marinas. And as mentioned VP, Powermist or other race gas brands.

[Dave Cofone]

I am afraid John is correct. There are no gas stations in NJ that sell non ethanol gas. The ones on the app have remarks stating they do not sell non ethanol. That is fine because we have plenty of regional airports to buy Av Gas from. I guess what I am looking for is why one would buy one or the other.....Price, performance, personal preference.....etc. When I was racing my my 2 stroke minimoto bikes I used Avgas. The imported bikes (from Italy NOT China) ran very high performance race engines that required at least 100 octane and zero ethanol..... Heat and lubrication were critical factors as the tiny engines would put out (under 40 cc) between 6 and 18 hp at 15000 rpm. So I just assumed everyone ran Avgas but I am too new to the Yamato engines and want to keep mine in top condition........

[dwhitford]

While I have no direct experience with Yamato Stock engines, in general for the compression ratios of most Stock engines, you're better off with the lowest octane you can get. The reason for this is because the additions to ''pure '' gasolines (tetraethyl lead, benzene - Amoco in olden days) all tend to lower the heat output of the fuel to help counteract detonation. In general, Stock outboard compression ratios are so low that detonation is a non-problem so long as spark-advance timing is reasonable.

So what you really want for best performance and speed is a gasoline that produces the most heat per milliliter . . . in plain words, the lowest octane you can get.

[ZUL8TR]

Comp ratio (CR) based on the cylinder volume above the top of the exhaust port using E dimension and combustion chamber volume (CV) per APBA inspection manual:


Y80 14mm head = CV 18.5 cc = CR 6.7:1 +/- Min 86 octane per owner manual
Y80 18mm head = CV 18.0cc = CR 6.6:1 +/- Min 86 octane per owner manual
102 14mm head = CV 25.5cc = CR 5.6:1 +/- Min 86 octane per owner manual
302 14mm head = CV 25.5cc = CR 5.7:1 +/- Min 86 octane per owner manual
321 14mm head = CV 25.5cc = CR 5.7:1 +/- Min 86 octane per owner manual

102 has greater E dim than 302 and 321 thus lower CR

All are relatively low compression engines, why manual has 86 min fuel

https://www.apba.org/sites/all/files...1-27-19%29.pdf

[Bob Rusnak]

Went to stock car track and bought Sunoco race fuel from them. It is not cheep! I think I paid $8.00/ gal.
I have a question, will Blenzol mix with gas and would it be suitable for 750 mod Merc?

[mercsami]

dwhitford is correct, the lower the octane the easier it is to ignite the fuel in lower compression engines.

[Bob Rusnak]

This day and age pump regular pump gas from any gas station should be legal. Ethanol is here to stay. It add nothing to the performance.

[dwhitford]

Right, Bob. If anything it detracts from performance. But you need the correct gaskets and seals in the engine and overall fuel system to stand up to the ravages of the ethanol ''enhancement''. For example, in a standard Merc fuel pump as used on mod engines, I think the gaskets can survive OK, but I won't bet on the longevity of the diaphragm.

[Art K]

Use ethanol in our Mod Mercs. Legal in NBRA, no performance advantage that I can detect we use mid grade. NBRA does have a gas standard and does test fuel. Been using it for years with no problems with gaskets, seals or fuel pumps.

[Larry M]

Use ethanol in our Mod Mercs. Legal in NBRA, no performance advantage that I can detect we use mid grade. NBRA does have a gas standard and does test fuel. Been using it for years with no problems with gaskets, seals or fuel pumps.

When we started using ethanol ( NBRA had an ethanol sponsor) and you had to run ethanol to be eligible for the prize money.
I tested some of the o-rings and rubber in ethanol and it did have some effect on them. Some people cussed it and other people said they didn't have any problem. If I have a choice I would run straight gas. Just my 2 cents worth.

[Syd Marsden]

I know it drops performance my Hemi a 273 course from 1957 dropped about 300 FPS on the top end when I had to use ethanol fuel it came right back when I could get non ethanol again. Also had to run the engine faster to run the same speed