Mixing e85 and 91 question

[sbeck]

I have read that its safe to add about 2-3 gallons of e85 when filling up with 91 to make it 93-94 octane without changing any fuel trims or timing to help limit detonation. Has anyone tried this?

 

[Bud92gsx]

I run about 2 gallons of e85 in a tank of gas..

 

[95gstSwish]

why not just use 93 octane on pump?

 

[1990AWD]

why not just use 93 octane on pump?

Because he may not have 93 pump.

Mixing pump gas and E85 just weakens the mixture. All E85 is is 85% ethonal and 15% gas so the more gas you add, the less % of ethonal there is.

 

[broken_eclipse]

I've done this with my LS/vtec hatch, my DSM (before it went full E85), and a friends A4 all with great results.

 

[calob_95tsi]

I actually tried this today but with 5 gallons of e85