If you are talking pump gas you are off your rocker if you think racers would trade there race gas for e85. I run straight methanol race fuel in my panhead. There is no way I would show up at a race track and mention that. I would keep that on the down low. just so you know. TRUMP!
TECHNICAL FEATURE
Knowledge Boost: Ethanol Explained
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Andre Simon
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Ben Silcock
20TH APRIL 2015
113 COMMENTS
Hi Speedhunters, I’m Andre Simon and since this is my first “Knowledge Boost” article I thought I’d introduce myself. For the last 13 years I’ve owned a performance tuning shop in New Zealand called STM (not to be confused with US-based STM Tuned). While I’ve tuned just about everything from a 1,200hp jet sprint boat to private planes, my passion is import drag racing and over the years STM built or tuned cars that have set five world records on the drag strip.
My own Mitsubishi Lancer Evo III known as DOCILE held the outright Mitsubishi 4WD record for several years with an 8.23 @ 180mph and we also built and tuned an Evo IX known as DS9 that held the late-model Evo 4WD record until last year with an 8.34 @ 169mph. Over the time I owned STM I got frustrated with our industry due to the lack of knowledge and understanding held by a lot of engine tuners out there, and for the last couple of years I’ve been running
High Performance Academy with my business partner. Our aim is to improve the level of knowledge, results and professionalism in the industry and we do this by providing online training courses for EFI tuning.
Speedhunters has invited me aboard as a technical writer, which means I’ll be putting together an informative, tech-focused story once a month that will hopefully fill in some knowledge gaps and create some interesting discussions as we go. So with the introduction out of the way, let’s talk about ethanol. You’ve heard of E85 right? A pump fuel that can offer huge power increases from your engine for a fraction of the cost of commercial race fuels? Before you pull up to the pump and fill up, read on to find out if this is the new wonder fuel for you…
What is E85?
Unless you’ve been hiding under a rock, you’ll probably know that E85 is a fuel containing 85 per cent ethanol and 15 per cent gasoline. E85 continues to increase in popularity on the merits of sustainability and reduced emissions when compared to pump gasoline. That’s great for the environment, but if you’re interested in performance the real value of E85 is that it provides race-fuel properties at bargain basement prices. It’s quite possible to see your engine power literally double in some cases when switching from pump gas to E85. Obviously there’s a bit more to consider than just the fuel, but stay with me and we’ll get to the good bits.
How does E85 make more power?
E85 isn’t magic, and there’s some basic science behind why you can expect more power. The real merit of the fuel is in two of its properties: its octane rating and its cooling ability. Octane rating is a measure of a fuel’s ability to withstand detonation or knock. Too much boost or too much ignition advance can lead to detonation on pump fuels and hence the fuel’s octane rating often limits the power we can make. Increase the octane rating though and we can often make more power. The octane rating of E85 is in the region of 105, but when combined with its cooling properties, the actual knock resistance of E85 is much higher than the octane rating would suggest.
E85 also has a very high ‘latent heat of evaporation’. If you failed chemistry, don’t stress. In plain English this means that when E85 is injected into the engine, it goes through a phase change from liquid to gas and during this process it absorbs a lot of heat from the intake charge. A colder intake charge is denser and improves power, but also has the effect of making the engine less prone to detonation.
