E85 Conversion

[XfireZ51]

Originally Posted by LGAFF

Dominic it seems to me the Z already has the pump/inj capacity to run both....could you not just swap proms if need be to move back and forth between fuels?

Based on BSFC calc, the stock fuel system supports 537-572 hp depending on whether ur using 80 or 85% duty cycle on the injectors and assuming the injectors each flow 21#s/hr. So the heads/cams stock block modded motors are already close to the edge on the fuel system. Should be ok for stock motors. Then it becomes an issue of whether u r running E85 all the time or end up blending fuels which is where the fuel sensor comes in.

[Hog]

Some States run a Winter blend of E85 which is actually 70% Ethanol to help with cold starting encountered when ambient temps are low.

I would think that a few PROMs for a few different Ethanol compositions would work great for these differences. As X-Fire suggests, code to incorporate an Ethanol Composition Sensor would be ideal, but that's not going to happen anytime soon.

There seems to a variety available test kits that will give you the percentage of Ethanol to gasoline. Fill your tank, snatch a fuel sample, determine alcohol percentage, select appropriate PROM, away you go.
I haven't looked into any of these, just the results from a quick search on Ebay.
http://www.ebay.ca/sch/i.html?_nkw=ethanol+test+kit

[LGAFF]

Interesting comment, my TT V12 developed a misfire running winter blend, apparently a common issue in the Midwest with this engine.

[XfireZ51]

Maybe installing a Flex Fuel sensor and connecting to some sort of gauge for immediate readout. Then using a Prom Emulator like an Ostrich to download a pre-done calibration for the Ethanol content currently being used. Might think about calibrations in increments of 5-10% of ethanol content.
Obviously, this isn't for a daily driver and assumes the necessary fuel system capacity.

[Hog]

That Alcohol percentage readout from an alcohol sensor is a great idea, then you can adjust from that.

Question.
In the LT5 calibration is the IFR(Injector Flow Rating) 22.7lb/hr?

And the stock FPR holds rail pressure to 50.8psi at WOT. I was just running some fuel calcs and wanted to ensure I was using the correct base numbers.

Thanks.

[XfireZ51]

Originally Posted by Hog

That Alcohol percentage readout from an alcohol sensor is a great idea, then you can adjust from that.

Question.
In the LT5 calibration is the IFR(Injector Flow Rating) 22.7lb/hr?

And the stock FPR holds rail pressure to 50.8psi at WOT. I was just running some fuel calcs and wanted to ensure I was using the correct base numbers.

Thanks.

Yes, its 22.7# altho I'm not so sure the stock injectors actually flow that. I had the Accels flow tested and they came in at ~ 20.7# @ 43psi.

[Hog]

Originally Posted by XfireZ51

Yes, its 22.7# altho I'm not so sure the stock injectors actually flow that. I had the Accels flow tested and they came in at ~ 20.7# @ 43psi.

So that 20.7lb/hr @ 43.5psi becomes 22.4 lb/hr @ the LT5's 50.8psi rail pressure.

Thanks for the confirmation.

[Hib Halverson]

An E85 converted first-gen LT5?
Seriously?!

The cost of the conversion to gain a small power increase would be obscene.

You'd likely have to change:
Fuel tank
Fuel pumps
Fuel lines
injectors
and, of course, calibration.

You'd also have to add an ethanol sensor in the system because virtually no pump E85 is consistently 85% ethanol. The proportions of alcohol in pump E85s vary widely. The only E85s which are consistent are racing blends such as Rockett Brand Racing Fuel's "E85 112".

You'd also have to add some alternative engine controller capable of varying the injector duty cycle according to the ethanol sensor's data.

[LGAFF]

Originally Posted by Hib Halverson

An E85 converted first-gen LT5?
Seriously?!

The cost of the conversion to gain a small power increase would be obscene.

You'd likely have to change:
Fuel tank
Fuel pumps
Fuel lines
injectors
and, of course, calibration.

You'd also have to add an ethanol sensor in the system because virtually no pump E85 is consistently 85% ethanol. The proportions of alcohol in pump E85s vary widely. The only E85s which are consistent are racing blends such as Rockett Brand Racing Fuel's "E85 112".

You'd also have to add some alternative engine controller capable of varying the injector duty cycle according to the ethanol sensor's data.

Its been done successfully by other C4 Owners....you don't need to go to the extreme that you have listed, pumps...tanks do not need to be changed, and I do my own work....so not a big deal or expense. I am at 441RWHP NA so looking for options as hitting the limit....and then theres the 75 shot of nitrous

[rkreigh]

Originally Posted by tpepmeie

The only reason I can think of that you'd *need* a new ecm is if you wanted to run different blends of E85 and unleaded. Then you'd need a flex fuel sensor and the ability to modify the fuel pulse for varying stoich ratios.

Other than that the stock ecu would work fine, with the proper calibration.

I come back to Lee's original question and I don't know why one would do this on a naturally aspirated engine. There is much less energy in a gallon of ethanol compared to pump gas so I can't fathom how it makes more power normally aspirated. Now if you're running boost and can benefit from the charge cooling effect then ok. But that's not the situation that was proposed.


Sent from my iPhone using ZR-1 Net Registry

emissions. and of course upping the compression and still running cool. E85 is good stuff. But as Todd points out, it's really not worth the cost (new pumps, injectors, calibration, fuel filters, really the whole fuel system) to gain a few ponies.

However if you are going to boost it, or go super high compression, it might be worth it.

For me I'd love to try it to clean up the HC. The LSV has bad breath and HC are still up above 120 on a 48 standard.

Some fresh cats MIGHT clean it up enough, but I'm going E85 on the turbo car so the LSV might like a drink too.