Im looking at setting up a 4-71 blown 283 for my A. Im also looking for a Hilborn 2 pot injection unit for it. The question is can the injection be set up to run fairly reliable on the street? Will it work with a high pressure electric pump?...or converting it to EFI the best route. This car is a double duty car but most of the time is going to be spent (in a million pieces in the garage) on the street. Any useful or non useful info appreciated. Signed; Trying to Get Blown
While it may not be very faithfull to an all-out "Traditional" build, the EFI route will make a better street set-up than the older mechanical fuelie units will. Not that you CAN'T get away with running Hilborns on the street, but it represents a compromise of what the system was designed to DO. The older, drag-race fuelie set-ups were meant to provide lots of fuel for wide open throttle acceleration, with little thought given to idle quality and part throttle operation. There are some slick set-ups being built that look like vintage carbs or fuelie units with modern FFI components "hidden" inside of them. They make for an engine that drives well under all conditions, yet still retains some "old school" character. I dig the old Hilborn, Enderle, Inglese and other fuelie rigs as much as anyone...but it sounds like you're after an all-around performer rather than a strip terror that will only see limited, if any, street duty. At least look into both sides of the coin before commiting to go with either mechanical or electronic fuel injection to be sure you'll be happiest with your investment.
watch for the november street rodder my friend kenny from classic gass has the cover(first time in mags history that one product gets the cover ) it will give you the run down on efi
From Hilborns website. Q: Can I run a HILBORN fuel injector on a street car? A: Our units are manufactured strictly for racing applications and are NOT recommended for street use. The castings are designed for maximum air flow and do not have a metering system for low speed operation. Where most street driving is between 2,000 and 4,000 rpm, racing engines idle at 2,000 and operate from 6,000 to 10,000 rpm!
I had toyed with the idea of making a fuel injection set-up for my mini-bike, using the old, worthless diaphram style carb as a throttle body. The plan was to throw the diaphram away, and fit a fuel fitting onto the diaphram cover. A small, engine-driven pump would then be mounted to deliver fuel into the original carburetor inlet, then return it to the tank via a new return line. This would pressurize the fuel in the small chamber that leads to the orfices that feed fuel into the venturi, and would FORCE fuel flow through them...with the two mixture screws to control flow volume. RPM would dictate the flow rate. This plan also called for inverting the "carb" to make it a down-flow design. I think it would probably work...but only really under W.O.T. conditions...I'd have to believe that it would tend to flood out when the throttle was closed, and would likely not idle well, (if at all!) either. In short, I reasoned that although such a project might be fun to try, I'll be happier running a carb so I can ride this thing everywhere! Might still try my idea out on another mini-bike, or just an old engine running on the bench to see if it works...but I think you'd experience some of the same problems I'm anticipating if you opted to try and run drag style mechanical fuel injection on a street engine...they're simply not ideal for idling around and part throttle operation so neccesary for a dependable street engine.
Thanks for the input fellas.... Ive been checking some of the conversion websites...youch a little steep for me. I guess carberation is the way Im gonna end up going. Signed; STILL Trying To Get Blown
Umm...you don't need injection to get blown! (Carburetors work very well on supercharged street engines!)
Must be a way an enterprising guy could use one of the GM TBI setups hidden in the throats of that 2 port.
You still need the edit the butterfly's don't care what they are from and to my knowledge you cannot run a high pressure electric fuel pump on mechanical injection. I run Hilborninjection on my race car it can be driven on street but you won't like it. Efi conversion is the way to go but as yo found out expensive. It depends on what boys you want to play with. Pat
Injection is a "little" easier on the street, with a blower. The electric pump idea won't/don't work. But.. with the main tank out back, an electric fuel pump keeps the spun aluminum tank out front, full to feed the MFI pump. Since there's no accelerator pump with MFI, a manual Trans is the bee's knees to make it easier to clean it out. They run better-er with a magneto, also
Mechanical injection is less sensitive to temp and humidity when you use methanol. Running mechanical injection will always be a compromise and you will have to stay on top of it . It can be done ,but not by everyone. Carbs are much easier or an EFI conversion .
I found a way to do both efi and mechanical injection. My rebuilding after the crash thread covers it in depth.
Just thinking out load here but the Bosch mechanical injection used in the 80’s on vw , Mercedes’s etc. I’m thinking could be adapted to this set up Individual injectors the “ mixer “ or diverter is vacuum controlled to varie fuel delivery Lots of 4,6,8 cylinder set ups out there Not much goes wrong with them if the system has never been diddled by someone who don’t know what they are doing. Maybe something to look into The fuel distributor can be mounted anyways The vacuum modulator is what controls fuel flow and is mounted in the air filter housing There is guys that have mounted it to the throttle valve or ran a cable to the gas peddle with varying results
I'm looking forward to ElMir.. see you up there! I been busy, but I lurk here and there. I didn't look at the orig OP date!
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