since im going fuel injection

Discussion in 'High Tech for Old Iron' started by garyd, Dec 24, 2018.

  1. garyd

    garyd Well-Known Member

    on a street driven car 95% stock except intake manifold does it matter if i get the holley sniper speed bore or square bore. the holley quadrajet fuel injection kit is 250$ more
    my car is a 75 park avenue with dual exhaust and an edelbrock performer intake manifold . its a spread bore intake. i dont race or drag or anything. i have stock pistons and cam and heads for 75. i thin the engine has 250 hp max but plenty of torque. i do not want to buy the wrong one
    is the one they said i need
    here is the one i wanted to initially buy
  2. garyd

    garyd Well-Known Member

    car came from factory with hei
  3. Mark Demko

    Mark Demko Well-Known Member

    Why fuel injection?
    Just to update it?
  4. Kaule

    Kaule Gold Level Contributor

    the spread bore seems to have the progressive linkage that opens the secondarys later,
    i have the sqare bore unit because there was no spread bore unit at the time i was looking for FI

    it was difficult the start without squeaking tires and i have only a 350, so i have done the progressive link mod by myself

    later i have replaced the linkage with this one from holley:

    but the description from the spread bore unit says you need an external fuel pressure regulator, at the square bore the regulator is built in,
    so there is some extra $

    i would prefer the spread bore, but both should work

    hope you can read my bad english o_O
  5. garyd

    garyd Well-Known Member

    the reason is my carb is bad. im tired of dealing with it. plus it needs rebuilding.
    i figure the fuel injection will help engine run better and more precise. plus a slight uptick in mpg.
    the external pressure regulator im glad you mentioned it. i would of never seen that. its only 55$ more so its not too bad. so not im looking at 1300 before the fuel pump. im debating now whether to go inline pump of the in tank one. the in tank one is 450$ more .
    im glad you did a write up on your fi problem. it sucks having to find this out on your own.
    i wonder why they did not include the linkage in the kit
  6. Ken Warner

    Ken Warner Stand-up Philosopher

    Gary, have you read about the other fuel injection installs here at V8buick? Your message above look like you are counting every dollar here and I can tell you first hand that you are going to spend quite a bit more than the price of that kit before you have the system running the way you will want.

    External pumps are a crapshoot but it seems like most things in life you get what you pay for. The $100 chineesium pump that appears like a good deal will leave you stranded. If you are lucky it will just be in your garage. In tank pump is THE WAY TO GO but some guys do ok with external. The HEI may work fine but a lot of people have trouble getting a clean tech signal off of them for the various fuel injection systems so an MSD (or similar) may be needed. If you want to use the timing control features that may be available on the FI system you may have to buy an entire distributor. Last but not least your new fuel pump and FI ystem are going to need more current than your stock charging system will supply. If you have an 80ish amps or better alternator you may be ok but generally a 100+ amp alternator is recommended. (Your stock mid 70s alternator MIGHT be 63 amps of you are lucky.)

    One more thing, the consideration of square VS spreadable style base seems trivial to me. A thin steel adaptor from Edelbrock is only about $15 and won't cause you any clearance issues with the performer manifold. Seems a cheap and easy solution considering the cost of the regulator and additional Fuel fittings you will need it you stick to the spread bore throttle body plan....
    sailbrd likes this.
  7. Mark Demko

    Mark Demko Well-Known Member

    Have one of the Q-jet guys on here fix it, way cheaper than fuel injection, plus there’s really not much in the way of a performance increase, nor in drivability or economy verses a well running and calibrated carb. Emissions are the biggest reason fuel injection was instituted
  8. 1973gs

    1973gs Well-Known Member

    There's nothing wrong with using a carburetor, but I'm glad that I went the fuel injection route, especially with my engine that is far from stock. If the ecm doesn't or can't learn and correct an improper air fuel ratio, I can simply adjust it with the hand held programmer. I don't have to change jets in the carburetor. When I was younger, it didn't bother me to remove a carburetor multiple times to make changes, but it's a lot easier to make changes from the drivers seat! Plus, with fuel injection, you can lean it out on a long road trip to get better fuel economy and richen it back up when you arrive at your destination. I have a 523 that averages 10.1 mpg. I don't think that would be possible with a carburetor, IIRC, I only got 11-12 mpg in my car when it had the 350, but I was only 16 and had a lead foot. For the fuel pump, it's always better to push the fuel rather than suck it from the tank. That being said, I used an inline pump because I don't want to drop a full tank to replace the pump. If I ever redo my fuel system, I would probably use an in tank pump and install an access door in the trunk. I wouldn't get the pump kit with the fuel injection system. I have the FAST EZefi and the cheap pump failed at 200 miles and the supplied wire harness kit only had 18 ga wire so I had to run new 10ga wire for my new pump.
  9. 72gs4spd

    72gs4spd Well-Known Member

    As for the the throttle linkage I used the Sniper throttle extension part #20-16. Made it less critical. I spoke with HOLLEY tech and they don’t recommend converting a square bore to progressive. They did say the extension is what is needed. The pedal feels similar to what it did with the Quadrajet with the extension. Should have it up and running this weekend.

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