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Anyone use that Holley 670cfm Holley throttle body?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by dale_gribble, Oct 19, 2006.

  1. dale_gribble

    dale_gribble Registered Member

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    My truck has been idling rough, and the fuel injectors are actually starting to get noisy. I just recently replaced the original fuel filter after about what, 20 years? I could barely blow through it.

    Anyways, the fuel injectors are about $120/ea for a decent OEM equivalant, so I did a search on ebay, and low and behold a new Holley TB for my truck for $199 buy it now + $20 shipping. This same TB is $420+ from Summit Racing.

    It is a direct bolt on for my truck with new injectors included and I think the throttle body even has an adjustable fuel pressure regulator. They claim 25% HP and torque, but as far as I am concerned as long as I don't lose anything, I will be very happy.

    [​IMG]
     
  2. bowtiepower00

    bowtiepower00 1/2 ton status

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    Some of the guys at thirdgen.org run em on their Camaros. Supposed to be a good unit, hard to beat that price. I'd go for it. The bores are slightly bigger, for best results you may have to enlarge the openings on the intake a little bit and/or add a spacer.
     
  3. Cricket

    Cricket 3/4 ton status

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    You can have your manifold bored out to 2" at the local machine shop. I also see bored out Edelbrock TBI manifolds on shmebay from time to time.
     
  4. southernspeed

    southernspeed 1/2 ton status GMOTM Winner

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    BobR from from Dynamic EFI says that the earlier Holley injectors with the black round caps (as in that picture) are junk and will never run right. They'll work, but you'll always have idle issues at least. It's in one of his posts on Thirdgen somewhere. The later ones are ok. Make sure what type this guy is selling. Maybe that's why they're cheap?
     
  5. dale_gribble

    dale_gribble Registered Member

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    This is an actual picture of the unit... They don't have the round caps. We'll see I guess

    [​IMG]
     
  6. southernspeed

    southernspeed 1/2 ton status GMOTM Winner

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    Yeah, that's the later one. The one in the original post is the early junk one.
     
  7. Txchevy18

    Txchevy18 1/2 ton status

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    Not sure if this will effect you or not... Ive been looking at this setup for a while and after reading holley's website noticed that its olny rated for 275hp. I figure ill just spring for the truck advenger or go all out and get a tpi setup. Good luck w/ the rig and let us know if you do get it.
     
  8. skratch

    skratch 1/2 ton status

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    If I was doing this I would go with the slightly lager big block version, and then get a vacumm referenced fuel pressure regulator from GM. The part number can be found on third gen or 454ss.com, I don't remember it right off the top of my head.
     
  9. scotto0609

    scotto0609 1/2 ton status Premium Member

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    I just put a whole retrofit holley projection on my 85 big block. It is the old style and runs fine for now.This system had its own ecm,fuel pump,wiring. It also has a o2 sensor to convert it to a closed loop system supposedly will run even better with it.
     
  10. bowtiepower00

    bowtiepower00 1/2 ton status

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    That holley unit is capable of making plenty of HP with larger injectors. The 454 TB is not a direct replacement. The electrical connections, bolt pattern, etc., are different. You will also have to replace the injectors unless you're running a custom PROM tune. They are becoming hard to find and expensive. The GM AFPR has been discontinued. I would recommend the upgrade if you're building your engine, but you'll have to use an aftermarket model and plumb it in somewhere. Keep in mind that bumping the FP is a band-aid solution, and without PROM tuning it will not work to it's fullest potential. I would bolt in the Holley and not worry about it.
     

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