words: Bruce Parker, photos: Colin McCarty
Editor’s note: Bruce Parker is a longtime member of Audi Club. He is part of our Performance Driving Education Committee (PDEC), a MSF Level 2 Instructor for Audi Club, BMWCCA, Porsche Club of America, and is a doctor who has a history of medical insight of motorsport events…with the occasional excitement.
Last fall I taught at Road America for the BMW club of Wisconsin. One of my students had an M3 with a turbocharged in-line 6 cylinder motor. He had converted his motor and management system to burn E85, mostly using General Motors parts. His goal was power, not saving the earth. When we inquired, we found 7 others who had similarly converted their cars. Consensus held that they had achieved an approximate 30% increase in peak power, at a cost of increased fuel use by volume. This experience may apply to other brands.
I convened an informal discussion group of their friends who had not performed such a conversion, and told them of the work done by the Clean Fuels Development Coalition, a non-profit public interest group in Bethesda, MD. Some of us are old enough to remember leaded fuel. Tetraethyl lead allowed increased compression ratios by slowing the flame front after spark ignition, and by suppressing (early) compression ignition of gasoline. Lead was replaced in the early 1980s by a group of chemicals with a single six carbon ring – benzene, toluene, xylene and others. These are all classified by the EPA as toxic and carcinogenic. Their combustion products are merged molecules – from 4 to 7 ring structures – which are just as toxic but more stable.
By agreement with the EPA all spark ignition vehicles sold in the US from 2001 onward are tolerant of E10 [10% ethanol] which is about 95% of the gasoline sold in the US. Ongoing research has found no problems using moderately higher fractions of ethanol in standard spark ignition gasoline motors since model year 2001 (University of Nebraska, Lincoln). Increasing ethanol from 10% to 30% in premium gasoline allows reduction of aromatic hydrocarbons by about half.
I have experimented with my unaltered turbocharged vehicles, and have noted no problems. All start promptly, down to -12F to date. The diminished mileage per gallon with E30 gasoline is balanced by a greater reduction in cost. E30 has an octane rating of 94, allowing some cars to make more power than on 91 octane pump premium fuel. One car – a 2016 Audi A3 e-tron – had a normal mass spectroscopy motor oil analysis report from Blackstone after burning E30. I have also tried this fuel in a 2003 B6 A4 Avant, and a 2006 B7 A4 Avant. I have not tried this with any pre-2001 vehicles.
Diesel motors got adverse publicity in the ecosensitive world, largely because of visible smoke and proximity to children on school buses. The damage signal for children exposed to higher levels of polycyclic hydrocarbons is not distinguishable between diesel and gasoline exhaust. Message: Do not live near heavily used highways, especially if young or old.
Use of E30 or E85 is not a final solution, and all the problems with fuel ethanol production remain. My take on this is that use of E30 in appropriate vehicles offers a net benefit.
Background data & discussions can be found by searching for the Clean Fuels Development Coalition on line. They have a short form white paper, and a long form deep discussion on their web site.
I have found variable access to E30 whether premixed, or at variable mix pumps, or by “splash blending” with useful location information by searching for E30 or E85 near me. There are several sites with variably dated information. Gas Buddy will allow searching for E85.
