In my quest to be environmentally friendly and to continue my "GREEN" theme I've decided to convert my 69 Camaro to run E85. The simplest way to do this is with a carburetor conversion. I considered Fuel Injection, but want to keep the cost reasonable and complexity to a minimum.

So what is E85?

Source: wiki.answers.com/Q/What_is_E85_fuel

E85 is an alcohol fuel mixture that typically contains a mixture of up to 85% denatured fuel ethanol and gasoline or other hydrocarbon by volume. On an undenatured basis, the ethanol component ranges from 70% to 83%. E85 as a fuel is widely used in Sweden and is becoming increasingly common in the United States, mainly in the Midwest where corn is a major crop and is the primary source material for ethanol fuel production.

E-85 ethanol is used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel engines are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. The primary differences from non-FFVs is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system, the use of fuel pumps capable of operating with electrically conductive (ethanol) instead of non-conducting dielectric (gasoline) fuel, specially-coated wear-resistant engine parts, fuel injection control systems having a wider range of pulse widths (for injecting approximately 60% more fuel), the selection of stainless steel fuel lines (sometimes lined with plastic), the selection of stainless steel fuel tanks in place of terne fuel tanks, and, in some cases, the use of acid-neutralizing motor oil. For vehicles with fuel-tank mounted fuel pumps, additional differences to prevent arcing, as well as flame arrestors positioned in the tank's fill pipe, are also sometimes used.

Use of E85 results in reductions of greenhouse gas emissions and energy use for each gallon burned, compared to the emissions and energy use for the gasoline it replaces.

Using corn based fuel ethanol production, E85 has a significant effect on total fossil fuel / energy usage and greenhouse gas (GHG) emissions. As process efficiency increases over the coming years, these benefits are expected to continue to improve. A recent study by University of California at Berkeley estimates it cuts greenhouse-gas emissions by 13% over gasoline.

105 octane E85 fuel produces less energy per gallon than gasoline, translating in fewer miles per gallon; however, the higher octane allows for greater horse power performance. Unless E85 is 15% or lower than the price of gasoline, consumers won't see any savings in fuel costs per mile; however, even at higher prices the consumer aids the farmer and sends less money to terrorist funding countries. Thankfully, the average e85 retailer sells this product for at least 15% less than 87 octane regular gasoline. This makes e85 fuel a win win situation for everyone except oil producers.
 

The conversion.

I've looked at several companies out there and have decided to use Heath Daniel's RaceonE85's kit. His site is http://www.raceone85.com/ I'm going to use the Stage II 850 CFM kit where I'll just use my base plate and float bowls from my 4781 850 Holley double pumper on a new aluminum body and metering plates.

The key points of E85 are: 105 octane rating, it is a renewable fuel source, it is environmentally friendly, has a higher tolerance for detonation, and will allow you make more power.

The only draw back is you will have upgrade your fuel system to flow  30% more fuel.

Here is an interesting video from "Change2E85.com" where a "non" flex fuel GM Vehicle was run on E85 with no changes. Interesting....

So onto my project. Here it is, a return style system with a Holley 850 (4781).

Parts consist of an Aeromotive 11203 electric pump, Holley 803BP bypass regulator, 20' of #6 braided and a bunch of Russell fittings. I also modified the stock sending unit to add a 3/8 return line. The pump makes about 14 psi and the regulator is set to 6 psi after the carb. There are also two gauges - one at the carb, and on in the dash on an isolator to confirm pressure. The  pump is good for 700HP - I'll probably need to up the feed side to number 8 or 10 at some point. I also added a billet fuel filter before the pump and at the return line before the tank. There are also brass \ bronze filters in the fuel bowls as added protection against dirt.

The 4781 Classic Double Pumper was purchased from Summit Racing and it was modified with a jet, power valve, and a front 50cc accelerator pump kit.

The key point to the RaceonE85 kit is that it is cheaper than just buying a new E85 Carb and allows for the reversal back to gas quickly. I'll most likely bolt the 850 back together with Holley, Quick Fuel, and Proform parts.   The other issue I will struggle with is E85 isn't too readily available here in Austin TX. There is one E85 station 6 miles away, but still worth the conversion. 

Part of my disassembly is to empty the fuel tank. I'll be draining my cars fuel tank with the existing Aeromotive electric fuel pump.  

Note in the picture the fuel pressure isn't regulated until after the carburetor.

The big brown truck just left a box of parts! Inside was a ton of stuff from RaceonE85 and Quick Fuel Technologies.  Here is the list of the 850 4150-E85 Conversion Kit:  (2) Billet Quick Fuels E85 Metering Blocks with gaskets,  (1) 850 CFM E85 Calibrated Quick Fuels Main Body,  (2) .130 Stainless Steel Needle and Seats,  (1) 3.5 Power Valve with Gasket (1) Power Valve Plug,  (2) 50cc Accelerator Pump Diaphragms,  (2) #86 (2) # 94 Main Jets.

A quick note here is that the kit is custom configured for your engine and carburetor setup. Heath was great in the sense that he realizes no two engines are a like and as a result each carburetor is tuned differently. The parts lists in my kit will differ from kit to kit based on customization for the application. Here is a picture.

OK, Let's start - here is the 4781 850. Let's go through the tear down to show what is going to change. If you do not have non-stick blue gaskets, you'll be in for a extra work cleaning up the gasket surfaces. Be patient and careful. Fuel bowl removed on the bottom right. If you have any question regarding your Holley Carburetor check here at Holley's Website for more information.

The main body and metering plates are going to be replaced with the Quick Fuel components, but here is a comparison of the parts. The floats. float bowls, and base plate will be reused it this kit. A key point here is that the Quick Fuel Metering plates do not have a vacuum port for distributor timing.

My Ignition is full mechanical so no issue, however if you use a vacuum advance you'll have to get ignition vacuum from a different location.  Note the orange check valve in the fuel bowl - you may have a ball bearing. Install the correct power valve and jets into the Quick Fuel Metering plate. The metering plates are identical so set each up for either the front or back with the appropriate jets and power valve, and or power valve plug.

I reused the Holley center discharge nozzles from the 850. They were #37 front and rear. New ones are on order from Summit Racing and I have a few old ones that I will sacrifice by re-drilling for tuning. The front fuel bowl and metering block mocked up. Note the pin under the discharge nozzles goes in point down.

Note: You cannot use standard Holley Discharge Nozzles tapered screws with the Quick Fuel main body. I did and the accelerator pumps were hydraulically bound. I replaced them with the ones that came with the Quick Fuel main body and everything is normal. Note the picture below I'm using the Holley Discharge Nozzles screws. I didn't figure this one out until I tried to start my big block and check throttle operation.

 Here is a visible comparison of the needle and seat along with the accelerator pump diaphragm. The needle and seat are replaced by a new one with a .130 orifice.

 Perform the same process for the rear metering plate and fuel bowl by replacing the needle and seat and accelerator pump diaphragm. Add the block off plate and jets.

After pulling my 850 apart I discovered it had a rear power valve in the Holley metering block. I pulled the valve and replaced it with a plug and  I increased the jetting from #80 to #86. I plan on reusing my Holley again and didn't need the hassle of playing with a secondary power valve. Holley did put blow out protection on both ends of the base plate. 

The E85 kit will use a power valve plug and the rear jetting is #94.  Here is the factory Holley main body, as well as, it separated from the Holley base plate. Last picture is of the base plate on the new main body. Note the location of the screws. The center two are left out by Holley.

With the E85 Carburetor bolted together its now time to bolt it on. Here are the left over parts. Hmmm, a Proform (Quick Fuel Technologies) base plate, and fuel bowls and I have a spare 850 gasoline carburetor. That will be another write up.

New e85 Carburetor!! Fuel and linkage still need to be connected.

Before and After

 The fuel tank has been drained and refilled with E85.  Surprisingly it started with no issues and had a much better idle quality.