Well based upon these numbers if we are talking costs...I think being able to run E85 even at lower MPG would likely be far cheaper.

E85 is normally about 15% cheaper plus the difference from having to run 91 or greater octane anyway with the car and you wind up with pretty much the difference.

My point being that I think our conversation about E85 is a mute point due to the cars requirement of high octane anyway. It's cars that run on 87 that don't seem to make up the difference.

@Darren Orange
Please at least read the wiki stuff you ninja edited into your previous post.

Yeah, it has been documented by people running E85 on our cars that its basically a wash between E86 lower MPG and E85 lower price, so its no benefit or advantage to either fuel type price wise. My point was not to keep debating the merits and cost savigns/money waste was E85, but that quantity of fuel can be measured as "fuel economy". :thumbsup:

Can you explain the point you are trying to make?

Right agreed with you on all points. I just wanted to get everyone back on point that running E85 makes realistically no difference in cost of operation.

Well, as of right now, sure. But we don't know how the motors will handle it long term. That could definitely raise the cost of operation, especially since it won't be covered under warranty.

The obvious problem with elevating boost for e85 on a supercharger is that it requires hardware to be changed out (the pulley). So, no easy switching between fuels. Better take a toolbox if you wanna drive anywhere that doesn't have e85, and don't plan any road trips lol.

You just need to reflash to a pumpgas compatible tune - no need to swap pulleys out just to go back to pumpgas.

There is apparently little gain to be had using the smaller pulley with pumpgas, but that's not to say it doesn't work with it.

Yea, either that or you could use a boost limiter. So if your running like a 20psi pulley and had to run 91 crap gas, you could theoretically just limit boost to 10psi. More torque early in RPMs too, because your 20psi pulley would hit 10psi a lot faster than a 10psi pulley would.

This is just based on speculation & random bits I've read on this forum, so I could be wrong. But I don't see why it wouldn't work if you limited boost lower for pump.

People in the miata community have been trying at limiting boost on superchargers for a long time, with various valves, restricors, even one I saw with a wastegate-looking setup. None actually work well that I know of. The proper way to control boost on a supercharger is by using the correct pulley.

Damn. If somebody could figure it out that'd be a great setup. My bad it sounded possible but just hearsay I guess.

This is terribly wrong.

E85 is not equal to 94-96 octane. lol

Better option is to use a constant speed drive between the crank and the supercharger. That would allow you to run the supercharger at max rpm at any engine speed...

I've never heard of this, sounds interesting...

Is that like a CVT? Sounds expensive?