Thinking real seriously about adding fuel injection

Discussion in 'Street/strip 400/430/455' started by Pro69GS400, May 10, 2020.

  1. Pro69GS400

    Pro69GS400 Well-Known Member

    So I have been looking through some threads in regards to fuel injection. Its hard to sort through. Those of you who have made the switch can you recommend which system offers the best bang for the buck? I’m looking at Fitech and Holley and frankly just can’t seem to come to a decision on what is the right choice. I’m kind of overwhelmed reading everything. The kits go by horsepower not cfm when ‘normally with Buick’s we spoke of minimum cfm in regards to fuel delivery. The engine this would be going on is a 430 with a healthy cam, TA stage 1 SE heads, currently has a dominator flanged SPX and a 4150 quick fuel 950. The bottom end I was told is basically stock 430 with ARP and stock valvetrain but with hybrid push rod combination I believe. I want to be able to go to the track and drive on street as well. So what are the thoughts on what may work for me?
     
  2. hugger

    hugger Well-Known Member

    Holley terminator stealth
     
  3. Schurkey

    Schurkey Silver Level contributor

    Don't expect more power than from a well-tuned Q-jet.

    Don't expect better driveability than from a well-tuned Q-jet.

    Don't expect better fuel economy than from a well-tuned Q-Jet. Probably worse unless it's got a "highway cruise" mode that allows leaner than stoich at steady speeds.

    Emissions control might be better than a well-tuned Q-jet.
     
  4. BillA

    BillA Well-Known Member

    Holley Sniper EFI with the Holley Hyperspark ignition system is the way I'd go if I were set on switching to EFI.
     
    72gs4spd and FoFiddy5 like this.
  5. Pro69GS400

    Pro69GS400 Well-Known Member

    Having issues now with current set up and if a throw money at it I’d rather it be towards fuel injection...I’m to the point where I am going to, take it somewhere to have them sort out the problem maybe I should just go towards injection now?
     
  6. hugger

    hugger Well-Known Member

    He has a SPX Dominator flange intake,...a qjet on that intake would be asinine

    What's the issue with the 950??
     
  7. Pro69GS400

    Pro69GS400 Well-Known Member

    Won’t accelerate with out back firing now and it hardly accelerates for that matter. I’m going to swap intakes out eliminate the adaptor and try again before giving up on carb. In my mind I think fuel injection would run so well but I have read post after posts of people having issues with FI also. At my skill level I would be possibly trading a problem for another.:(
     
    Mark Demko likes this.
  8. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    I wouldn't look to FI as a solution to your problem without eliminating other possible causes. 4150 DP carbs are easy to take apart and rebuild. Is it back firing through the carburetor or exhaust? Make sure it isn't an ignition problem. Check all the simple stuff. How would you feel if you put FI on it and it was doing the same thing? What have you checked to try and diagnose the issue?
     
  9. hugger

    hugger Well-Known Member

    Change the plugs first,..i assume since you have the adapter on there your not concerned with the added height...so I wouldn't change intakes just to eliminate the adapter its acting as a spacer is all,..

    You could have just picked up some debris under the seat,..or maybe a blocked bleed ,...4150 carbs are bulletproof

    Your surrounded by buick guys in Columbus,...I can give you a list buy some beer and take the car over and leave doing burnouts

    They will more than happy to do it,..that's what buick brothers are for
     
    Last edited: May 10, 2020
    Chuck Bridges and DasRottweiler like this.
  10. Pro69GS400

    Pro69GS400 Well-Known Member

    It ran fine. I noticed there was a crack in the adaptor. After changing the adaptor that’s when all my problems started. It wouldn’t idle, I got it to idle and it drives but quick, acceleration Results in back firing through carb. I suspect now at least the power valve needs replaced. To eliminate and start fresh I’m going to put a 4150 flanged SP1 on it and then see where I’m at and try to start trouble shooting. When trying to find an adaptor the transitions looked suspect. I purchased a nice Wilson manifolds adaptor and for,what ever reason it wouldn’t match up. So I ended up with a trans dapt and I just don’t think it is helping with my issues now. I think it changed the air fuel mixture greatly. I am not sure. I’m not pretending to know much about carbs and adjustments. I always had help but my help, is starting to thin out a bit as everyone ages.... C9DB611A-369D-4C5B-9785-1475AD9652E7.jpeg 2A0CFB1B-85E3-42F3-A475-A1B0C1F02479.jpeg
     
  11. Pro69GS400

    Pro69GS400 Well-Known Member

    With the new adaptor yea it was taller and I ended up adding a stage 2 scoop. B72AA58C-DE71-4710-8F93-468C0660FB74.jpeg
     
  12. hugger

    hugger Well-Known Member

    TA performance has a nice 1/2 in adapter..I ran a 4150 on 4500 intake several years back myself when I went to the procharger.

    I myself wouldn't pull the intake,...check your bolts to make sure you haven't developed a vac leak.

    To be 100% honest i would even look at just going to a Dominator they drive fine on the street

    Another idea for you to ponder,..reason I say this is because anytime I'm fixing something I try to upgrade I reccomend looking into a return style fuel system,..MUCH better than the deadhead you appear to be running,..cooler fuel,..happier pump,..more steady supply ..
     
    Last edited: May 10, 2020
  13. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    It's lean if it back fires through the carburetor. Put a vacuum gauge on it and spray around the flange with the engine running.
     
    stump puller455 likes this.
  14. Pro69GS400

    Pro69GS400 Well-Known Member

    When using the dominator on the SPX is a spacer required or suggested?is there clearance issues with linkages or anything?
     
  15. Pro69GS400

    Pro69GS400 Well-Known Member

    Larry I will check things out further tomarow and let you all know if I find something.
     
  16. cruzn57

    cruzn57 cruzn57

    who ever says any carb is smoother, responsive, get better mpg, than FI is delusional.
    mild sbc 350, start up is 10000000% better with FI.
    mpg hiway is 3-5 avg mpg better, with FI. performance is equal to carb.
    sorry, but someones is smoking some bad drugs if the seriously think ANY
    carb is even "as good" as FI
     
  17. hugger

    hugger Well-Known Member

    Nah since you have a 4500 flange intake,..a Dominator will be a direct bolt on no spacer or adapter needed,..but a nice tapered spacer is a good mod,..but no linkage will be the same has now
     
  18. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    Sounds like your plan is to load up the parts cannon and fire- hoping it solves your issues. Take the time and learn how to tune your carb and you'll be happy with it. Carbs got people around for nearly 100 years. Trust me they can be made to work.
     
    Brett Slater and TexasT like this.
  19. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    I find most folks would rather write a check for a couple grand than try to and learn how to tune a carb and distributor.

    Pit the archaic TBI fitech/sniper systems against a well tuned carb and you couldn't tell the difference. Sure, compare the fitech to the "elderbrock" 750 that was bolted on out of the box and i'm sure the injection is much better..
     
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  20. Pro69GS400

    Pro69GS400 Well-Known Member

    Well the thing is I have an SP1 I could use already, the dominator flanged SPX would solve the issue Of needing a dominator intake for a 482 build already in the works. I really would like to have the car running as soon as possible because I’ve waited along time to have a car as nice as this. I will try to identify the problem before just changing parts but also as I change parts I get a better understanding how things work if that makes since..... I just felt the adapted 4500 to 4150 carb was not the best performance combination and I would just rather have the right carb intake combination. It has caused problems because all is did was change the adaptor and it opened a can of worms
     

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