Discussion about mixing E85 with pump gas to raise octane.

[Old Mopar Guy]

Now after reading this article it seems to make good sense to mix E85 with pump gas, either 91 or 93, to yield a higher octane blend. The idea is to help keep the PCM from pulling timing, especially with the summer here. As a benefit it will also cost less to fill a tank with a blend rather than straight 93 for example. I would consider a blend of 3:1, that’s 3g. of 93 to 1g of E85. To go from 93 to 95. Clearly we need to also consider that some pump gas does contain 10% ethanol. So I question the guys in the know as this seems like a no brainer, even for a street car like mine. I’d like to hear thoughts on the potential downside as there is no “free lunch”. Thanks all.

https://www.enginelabs.com/engine-t...ump-gas-getting-higher-octane-for-less-money/

 

[vortecd]

@jonx96

 

[jonx96]

Mixing in a could gallons of e85 will bump up the octane of the 93.
but a few things to consider.
it is already a known issue that these cars max the injectors out when entering cot. The e85 will just make them max out faster.
fuel trims will also have to add fuel because the e85 will make the car to lean out but should be able to accommodate a few gallons added to a full tank.

 

[Old Mopar Guy]

So it’s just not a matter of dumping in some E85 and going on your way. Thanks Jon.

 

[Speedy!]

I tried it a few years back before doing flex. It did help a tad with the STKR I'd see bone stock but the trims did get funky which isn't good so I abandoned the idea. Juice wasn't worth the squeeze.

 

[Old Mopar Guy]

I tried it a few years back before doing flex. It did help a tad with the STKR I'd see bone stock but the trims did get funky which isn't good so I abandoned the idea. Juice wasn't worth the squeeze.

Seemingly not. Thanks Speedy!