Quick Fuel Technologies offers a wide range of tools to handle this E85 conversion including metering blocks, E85 testing tubes and more. We will be using their 34-106QFT kit to swap our Gasoline blocks over to Ethanol blocks (larger metering wells) which still use Gasoline Main Jets and 6/32 emulsion bleeds.
1. We’ve had this RQ-1000 on our 496” Big Block Chevy for a few months now and while it performs great, the cost of race fuel is driving us toward new ventures. To start, yank it off the engine and take note of where your fuel lines hookup; Ethanol can be corrosive to rubber so make sure your pump/lines are rated for use.
2. The 34-106QFT kit comes with blocks, gaskets, baffles and even new hardware to make this job as seamless as possible. The instructions note to use the included gaskets as they are approved for Ethanol use, it is a good idea to use the new whistles and bowl screws as well.
3. The fuel bowl screws come out with a 5/16 nut-driver, take care to not lose the black nylon gaskets behind them (they are included in the kit, but it’s nice to have spares). Now is a good time to inspect the float for any cracks and verify your float arm is functioning correctly. With the bowl removed, we start by pulling off the block and removing any hardware such as jet extensions or power valve(s) as well as any leftover gasket material.
4. Now would be a great time to set our float height(s); Start by loosening our needle/seat hardware. Invert the float bowl as to allow the float to ride on our seat. Adjust the height of the float so that the mid-line (green imaginary line) is parallel with the casting lines inside of our bowl. This should be a great starting point and will set our fuel level roughly ½ way up our sight glass.
5. Power Valves can be removed with a 1” Wrench. These are sized based off engine vacuum readings.
6. Vent Whistles should be installed in a downward angle; Interference with bowl possible if installed at an upward angle.
7. With all of the gasket material removed we can install our new metering block; be sure to transfer over any hardware from our previous block (excluding jets). As for our jetting, QFT recommends adding +10 sizes to our existing jet(s). Once we have the baseline established, we can fine tune once our engine is running.
8. QFT has already calibrated the emulsion bleeds (arrows) as well as our Idle Feed Restrictors. They do not advise changing these unless you are very familiar with the emulsion circuit and how bleed changes affect it.
Above we can see a labeled metering block showing the different passages, it is important to install the metering block and main body gaskets on the proper side(s). Below we can see properly installed gaskets for reference.
NOTE: Because Ethanol requires at least 30% percent more fuel, you may consider using a larger pump nozzle. We had a .033 nozzle installed and upgraded to a .037 nozzle, ensure you have an Ethanol approved pump diaphragm (GFLT) as well.
QFT advises we use at least a .130 Stainless Needle/Seat (18- 10QFT), the Needle/Seat we removed was a .120 Viton Tip (notice the small black cone), Viton can have a negative reaction to Ethanol thus requiring a Stainless model. Bottom Left: Pictured is our .033 Nozzle we removed, note the Hollow Nozzle Screw that allows fuel to pass through.
9. When reinstalling our float bowl, make sure to use the new bowl screws/gaskets (left arrow) and torque them to 25-30 in/lbs. Ensure that our pump lever arm is installed on top of the diaphragm lever when reassembling (right arrow).
10. Our main jets, hardware, blocks can all be saved for a later date. While you can technically reuse the gaskets, if they sit for an extended period of time it is best to chuck them and install new ones.
We’re finished! Be sure to inspect your air bleeds for any dirt/debris and ensure our pump arm tension is correct. At WOT, our pump arm should fit a .015” feeler gauge. Reinstall any fuel lines or throttle attachments and bolt onto your intake.
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