E85Forum.com

staley52 · Joined: 17 Aug 2005 Posts: 9 Location: Washington, Iowa

I want to start experimenting with E85 in my 1980 chevy truck I just rebuilt the engine(just stock though) but there is limited E85 availibility here currently short of carring a second carb to swap on what could I do to have a happy medium of the two?

the truck is not a daily driver my commute is by pedal power, this truck moves when there is work to do(average weight 8000-15000lbs) and I would rather get 5mpg buying corn than 8mpg paying terrorists

is this possible or a pipe dream for the dual fuel

specialgreen · Posted: Thu Aug 18, 2005 4:29 pm Post subject:

I've thought about ways to try to give my motorcycle a "limp home" mode, running on gasoline. I've wonderend if I could add some kind of petcock to each intake manifold. When open, it would allow air straight in, bypassing the carbs. An air leak where the carb fits the intake manifold normally causes a very lean condition, but in this case, it might give a way to externally tune air/fuel ratio "in case of emergency".

At its simplest, this could be a tiny hole, normally covered by asbestos electrical tape. Even better, it could be a copper tube running to an adustable "pilot" screw.

With such a crude adjustment, air/fuel would only be perfect at one throttle opening (and you might need a dyno to get the same "ideal" speed on all cylinders). But if you tune it for cruising throttle, then it might allow you to ride a few hours home on gasoline.

With a car, you could go electronic: build an "air injector" driven from the O2 sensor!

OK, I'll admit that this is all very impractical Smile

.

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

Hey it works for NASCAR, that is one of the tricks they used to outsmart the tech inspectors on the restrictor plate races. They came up with a couple different "leaky manifold" solitions as I understand it.

The good thing is that running on gasoline in an E85 tuned car your running rich which is the safe failure.

If you had an AFB style carburator, all you would need to do is pull a couple screws and drop a different set of metering rods in the carburator to change the mixture. On other carburators an air bleed built into a carburator spacer would probably work just fine once you got it sorted out.

Larry

staley52 · Joined: 17 Aug 2005 Posts: 9 Location: Washington, Iowa

thats the bad part of my quadrajet not a easy jet change I have a carb spacer that I could set up with a valve to cause a air leak at the carb so the cylinders should lean out the same
is there a good starting point for the jet change ? up 2 sizes or 3

but good news a station 7miles from home is bringing in e85 hopefully in a couple of months

specialgreen · Posted: Fri Aug 19, 2005 9:22 am Post subject:

In my case, my carbs only have 2 fixed jets: a pilot jet, which is 0.375mm stock (0.40mm in Canada) and a 1.25mm mains.

For the pilots, I tried stock (0.375mm), #76 bit (0.508mm) and #74 bit (0.5714mm), which worked well at cold start, if maybe a bit too rich once warm. Probably 0.55mm would be ideal. That's 1.375 times the Canadian (non-EPA) idle jet size, and 1.47 times the US-EPA pilot jet size.

For the main jet, I guessed at 1.6mm, or 1.28 times stock main jet, and that seems to work.

There is also a needle jet, which is in sequence with the main jet, and I did not change the needle position (yet). Changing the needle taper is more work than I want to deal with.

Based on my experience, I'd say that you can try jets with sizes between 1.3 times the old jet, and 1.4 times the old jet. The change for idle jets can be towards the larger end: maybe even more than 1.4 times the old size. The change at wide-open-throttle can be towards the lower end, maybe even less than 1.3 times the old size.

Say, Hotrod, I saw your post on the Swedish forum about wideband O2 sensors. I've been wondering if it would be possible to use a narrowband sensor to help me tune my carburetor jetting. Would a narrowband sensor send 0.45 volts when the mixture is right?

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

specialgreen · Posted: Mon Aug 22, 2005 8:44 am Post subject:

staley52 · Joined: 17 Aug 2005 Posts: 9 Location: Washington, Iowa

well my e85 dreams have been put on hold, the station that was getting e85 decided that there was too much red tape and not enough demand currently but if demand goes up he will look into it again. maybe the rats I mean lawmakers Twisted Evil

will make it easier soon!@!@!@

staley52 · Joined: 17 Aug 2005 Posts: 9 Location: Washington, Iowa

on a good note it looks like we will be getting a biodiesel plant in town unless some lawyer screws us on that too Sad

Lgodave · Joined: 01 Sep 2005 Posts: 28 Location: WI

Hi,

I've yet to fill up at an E85 station, but I'm surprised to hear with Gas prices as they are that more people aren't trying out E85 in place of the expensive gasoline.

I suppose this is assuming that E85 is cheaper then Gasoline, near you.

What kind of Red Tape did the station have?

I'm not sure if your "former" E85 station did this or not but, the RENEW E85 stations to my North in WI have pumps that "Mix to order". You pull up to the pump and get any one of the following blends E10/E20/E85.

I'm sure some customers might stay away from E85 because of compatibility/performance concerns, but I suspect they might be tempted to use E20... which may lead to their using higher blends up to E85...

Mention it to your local station. If the main concern was compatibility, putting in an E10/E20/E85 type pump might increase traffic and sale of E85 fuel.