Top Lube for E85?
We had just switched to race E98 fuel in Dai Yoshihara’s Turn 14/Falken Tire BRZ at the start of the 2016 Formula Drift Season. Of course, we enjoyed the befits of the Ethanol’s high latent heat of vaporization right off the bat in the big 7-liter turbo RHS-Chevy that powers the car.
For the first time, we could advance the ignition timing until the power fell off, with no signs of detonation, and our coolant and oil temps immediately fell by 15 degrees. The engine was also wonderfully insensitive to minor changes in AFR, and we gained over 80 whp with no increase in boost pressure and very conservative tuning.
Admittedly, none of us had much experience with alcohol before. We all knew methanol was a superior fuel but highly corrosive, and it would require a lot of post event maintenance which would include pickling the engine and fuel system by draining the methanol and running gas through the system to remove the methanol.
With the heavy maintenance schedule a Pro Drift car needs, we figured it was not worth the advantages, due to it adding to our work load and annoying our hard working road crew who would be eager to pack up the pits and start traveling to the next venue or back to HQ.
Because of this, we decided to run a fuel that is 98% ethanol as a compromise. All was good until the fourth event of the FD season- a season that that was plagued with high humidity for those events.
At the New Jersey round, our car, which had been running beautifully, suddenly started to miss. Looking at the data, it was a lean miss even though the other parameters were ok. We changed out the injector of the missing cylinder and all was well for a few rounds but the miss re-occurred during qualifying even worse. Dai somehow qualified a car that had half its normal power and poor throttle response.
We replaced more injectors, but during top 32 eliminations, the miss came back with a vengeance. With no power, we lost and got cut early, a loss that was to cost us dearly at the end of the season in points.
When we got back to HQ and did some trouble shooting, we found that our injectors were stuck. The ethanol had absorbed water from the humid east coast air, which in turn had rusted the iron rich steel alloy armature of our injector pintles.
To prevent this from happening again, we switched to all stainless core injectors, but we would still occasionally lose an injector and a random fuel pump even though they had been reliable before on gasoline.
Currently, in Formula Drift, E98 is one of the most popular fuels with teams that are running forced induction, and in talking to other crew chiefs about our issues, we found that many of them were adding some sort of lubricant to their ethanol to prevent similar problems that they were experiencing.
Unlike gasoline, alcohol has little lubricity and is a powerful solvent. This means that alcohol can be very hard on injectors, pumps, rings, cylinder walls, valve guides, and seats. Anything the alcohol contacts, it can potentially strip of lubricant.
Some crew chiefs were adding two stroke oil and mixing as much as one ounce per gallon and even 3 ounces per gallon on rotaries. Some were complaining of lube separation when using two stroke oil. All said that adding some lube ended their injector and pump issues with ethanol for good. We decided we needed to run some lube as well and researched the best lube to use.