I'm wondering about E85 and my gas tank. The tank has to look stock (no stainless steel replacement tank), but needs to resist E85.
> If your car was built in the old days, it was had a lead coated, steel
> tank. The water in ethanol would cause the tank to rust from the
> inside out.
www.change2e85.com/servlet/Page?template=MythsIt looks like Spectra makes a nice replacement tank, the CR22A:
ecat.spectrapremium.com/ProduitsVehicules/vehicule/1093126But they only warranty it up to 20% Ethanol:
> SPECTRA PREMIUM warrants its fuel tanks for use with gasoline
> containing up to 20% ethanol (E20)
ecat.spectrapremium.com/bulletins/download/Warranty-Fuel%20Delivery.pdfThis article:
www.customclassictrucks.com/techarticles/0610ct_e85_for_your_truck/viewall.htmlsays:
> the original steel tank has to be replaced with either a
> polyethylene or high-grade stainless steel tank.
which seems incorrect. It looks like a tank can be internally coated.
This article:
consumerguideauto.howstuffworks.com/extended-use-test-welcome-2007-chevrolet-tahoe-cga.htmsays
> E85 vehicles require modifications to fuel delivery components,
> including a stainless steel fuel tank and Teflon-coated fuel lines.
which seems incorrect. It looks like a tank can be internally coated.
This report:
www.umaine.edu/mecheng/peterson/classes/design/2007_8/project_webs/csc_e85/pdf/report.pdftalks about lining a tank:
> Northern Fuel Tank Liner was sloshed around the
> inside of the tank, as per the manufacturer’s instructions.
> According to the manufacturer, this product is similar to the
> Novolac epoxy in that it is unaffected by ethanol.
The Northern Fuel Tank Liner instructions say:
> Northern Fuel Tank Liner is resistant to methanol, alcohol
> and other fuel additives.
www.racewayparts.com/tech/RW0125TankLinerBulletin.pdfPOR15 has a gas tank sealer:
> a high-tech sealer impervious to all fuels, including the new Stage
> II fuels which have a high alcohol content.
www.por15.com/US-STANDARD-TANK-SEALER/productinfo/TSG/-------------------------------------------------------------------
For E85 / gas tuning:
> To put some exact figures to this phenomenon, switching from 92
> Octane premium gasoline to 102 Octane E85 allows you ONE of
> the following options:
>
> 1) Increasing your boost level by 6psi of boost above your
> gasoline maximum boost level.
>
> 2) Increasing your static compression ratio by 2.5 compression
> points above your gasoline maximum safe compression level.
>
> 3) Increasing your timing advance by 13 degrees of timing
> above what you would use for a gasoline tune.
horsepowercalculators.net/e85-calculator/e85-calculatorwhen wanting to run either gas or E85, it seems the thing to do is set the compression ratio where gas will run, and then adjust additional timing when running E85. The alternative would be to set the compression ratio as much as E85 would allow, but there's no way to take out enough timing when running lower octane gas.
So FAST XFI can automatically adjust the AFR for E85 on the fly, but it doesn't have the ability to change timing on the fly. The timing is part of the map.
Here are some folks that retuned for E85:
On a CTS-V
> Car made 580 RWHP before E85. Three hours later on the dyno
> the car has a VERY conservative E85 tune (no more than 21
> degrees of timing anywhere in the load zone) and lays down 645
> RWHP. Just wow..... Can you imagine if this car had long tubes
> and an aggressive E85 tune (25 Degs)
It would easily clear
> 700 RWHP!! (on the stock blower nonetheless!!! Timing is an
> awesome thing!) Just wow....
www.cadillacforums.com/forums/2009-cadillac-cts-v-performance-mods/243180-just-tuned-11-v-e85.htmlAnother CTS-V
> Pre E85 we got 429rwhp
> Post E85 we got 487rwhp
ls1tech.com/forums/cadillac-cts-v/1221534-e85-converted-maggied-cts-v.htmlHere are guys that had a dedicated E85 tune:
> The 500 ci wedge, @ 12:1 AFR made 680 HP
> @ 11:1 AFR it made 760 HP
> @ 10:1 AFR it made 840 HP
> @ 8:1 AFR it made 920 HP
> I had to redesign the carburetor to get it to 8:1 AFR and the
> non-anodized parts began to corrode so I switched back to race
> fuel.
www.mopartech.net/showthread.php?t=8916These guys talk about 13:1 and 14:1
ls1tech.com/forums/13478927-post13.htmlThese guys are running 15:1 on a big block chevy:
www.yellowbullet.com/forum/showthread.php?t=88332-----------
Here's some interesting E85 / gas math.
> E85 ... reaches stoichiometry at an air:fuel ratio of 9.7:1
> compared to an air:fuel ratio of 14.7:1 for gasoline.
>
> By dividing those two figures into each-other it becomes
> apparent that an engine running on E85 needs 48% more fuel
> flow compared to the exact same engine running on Gasoline.
>
> E85 can produce 25.2 Mega Joules of Energy per Liter of fuel,
> while Gasoline can produce a more potent 33.7 Mega Joules of
> Energy per Liter.
>
> Your first thought, might be that gasoline is thus able to produce
> about 30% more horsepower on the same engine (because
> gasoline is a more potent fuel chemically speaking), however
> when you factor in that we are injecting 48% more fuel with E85
> to reach a complete combustion and stoichiometery, then the net
> result of those two figures is that E85 has the potential to deliver
> 11% more horsepower on the same exact engine, when
> compared to Gasoline.
horsepowercalculators.net/e85-calculator/e85-calculatorI think the concepts are valid, even if the math isn't.
14.7 / 9.7 = 52%, not 48%.
And E85 stochiometric seems to be 9.765:1
ethanolpro.tripod.com/id213.htmlwhich still gives 50%.
E85 energy density seems to be 25.65 MJ/L
while gasoline is 34.2 MJ/L
en.wikipedia.org/wiki/Energy_densitySo I get 14.7 / 9.765 * 25.65 / 34.2 = 13%
Back to:
horsepowercalculators.net/e85-calculator/e85-calculator> This 11% boost in power, is based on a straight gasoline to E85
> conversion. More power can be found using E85 by taking
> advantage of the higher octane rating and tuning specifically for
> E85
and it has an example:
> lotus is able to coax out an extra 51 hp or 19% more power from
> the same power plant simply by switching to an 11% more
> potent fuel mixture (as we mentioned earlier) coupled with
> another 8% coaxed through an alcohol specific tune with more
> aggressive mapping to take advantage of the higher octane and
> slower burn rate properties of alcoholic fuels.
Ahhh, 19% increase on 850hp is getting pretty juicy.
your friend in trying to keep up with the new Marin County Jenny competition curve,
arthur