E-85 is Horrible! What a joke!

[Kestas]

Originally Posted By: Cujet
Originally Posted By: Shannow
Originally Posted By: Cujet
I'd like you guys to know that it's possible to match a diesels thermal efficiency with E85. I'm not saying it's good, as there are problems with such a setup. Just that it's possible...


Pretty impossible to make such a system "flex" fueled


That's probably true, if we don't have a viable way to change compression ratio. However, interestingly enough, highly variable intake valve timing can "virtually" adjust compression ratio, and could go a long way towards making such an engine remotely feasible.

Just because we can does not mean we should. I'm in favor of the research, but that's about it. I'm not convinced E85, in it's current form, should be a mainstream fuel.

I've read where the automakers are toying with the idea of making variable compression engines by varying the position of the crankshaft on-the-fly relative to the head.

 

[Shannow]

Saw a Nissan prototype in the 80s, that had a multi-link conrod, connecting the crank, a control (semi stationary) crank and the piston.

The rotation of the semi stationary crank lifted the piston, changed stroke length and displacement.

Looking at the paraphenalia, it was the diametrical opposite of the ecoboost concept.

 

[Brons2]

Originally Posted By: Shannow
Pretty impossible to make such a system "flex" fueled


This is quite true. The current flex fuel vehicles are not optimized for E85. If they were, they'd have much higher compression ratios and/or turbo/superchargers to take advantage of the high octane. With the higher thermal efficiency, they would be able to get more of the energy content out of the fuel, which would narrow the efficiency gap with gasoline.

Of course, that would make the vehicles unsuitable for running on pump gas.

 

[supton]

VVT should allow for "variable" compression, while gaining Atkinson efficency (bleed off pressure under cruise, high compression for acceleration or when E85 is present, etc). I'd think turbocharging would be in the same arena.

While looking at Silverado's I noticed that the Flex-Fuel 5.3L has higher output while running on E85. Seems like the computer should be able to tell what percentage of ethanol is in the fuel, on the basis of that ethanol has more oxygen in it, thus throwing off the air/fuel ratios (requested versus actual). Thus the ECU could increase compression (close intake sooner) and advance timing. Assuming it's programmed in.

 

[Norm Olt]

Talk about a bad deal!

Check out the typical savings account annual interest rates versus the annual rate for a credit card: you give them your money for a year and get virtually nothin', they loan you money at 8-9-10% until your minimum payment is a day late and charge you a fee & raise the rate to 14-16-18%...

Brought to you by the same people that brought you E-85, FannieMae & FreddieMac, etc.

(No) Cheers!

p.s. 1st time I've ever heard of a "seat of the ear" difference! Is that like BMW adding a sound source (not from the exhaust) to make the M5 "sound sportier"?

 

[SteveSRT8]

You forgot Ford and Porsche, who both do a very similar trick to bring engine sounds into the interior.