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forced induction TBI

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Seventy4Blazer, Feb 21, 2004.

  1. Seventy4Blazer

    Seventy4Blazer 3/4 ton status

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    with a modified computer is it possible?
    or would it be best to do it with a TPI?
    i really want a 6.5TD but thats down the road a ways....
    Grant
     
  2. imiceman44

    imiceman44 1 ton status

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    [ QUOTE ]
    with a modified computer is it possible?
    or would it be best to do it with a TPI?
    i really want a 6.5TD but thats down the road a ways....
    Grant

    [/ QUOTE ]

    It is possible with a modified computer.
    The only thing is without the low compression, you can't safely use lots of boost.
    You can still wring out some more ponies without lots of mods so yeah go for it.
     
  3. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Stock 350 TBI is very low compression, somewhere around 8:1, might work out great with a 454 tb.
     
  4. CyberSniper

    CyberSniper 1/2 ton status Premium Member

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    Yes, but with the stock injectors you'll run out of fuel at the higher rpms. Even 80lb/hr injectors are only good for about 315hp.
     
  5. wayne

    wayne 3/4 ton status

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    [ QUOTE ]
    Stock 350 TBI is very low compression, somewhere around 8:1, might work out great with a 454 tb.

    [/ QUOTE ]

    Actually stock is 9.2:1.
     
  6. Hossbaby50

    Hossbaby50 3/4 ton status

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    You could probably do TPI with 30 lb/hr injectors and larger runners. Could probably support a fair amount of power. Much more then TBI due to the aftermarket components for the TPI. Throttle bodies, runners, plenums, injectors, etc. If you want some sick power TPI is definitly more power friendly then TBI.

    Harley
     
  7. Seventy4Blazer

    Seventy4Blazer 3/4 ton status

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    hmm, seems like to much work for a tbi i plan on replacing with a diesel...
    ill just supercharge my K3500 then... he he.. vroom.
    and then ill turbo the blazer...

    i wont be hitting to high an rpm with the blazer, i hope....
    a supercharger wouldnt be to much help in that instance. i dunno, maybe ill just have to put a big block inthe blazer with a blower...
    nah, nevermind. thinking through the keyboard again.
    thanks for all the replys
    grant
     
  8. fad2blk99

    fad2blk99 1/2 ton status

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    I could be wrong here, but along with adding more fuel your timing curve will have to change as the boost increases. Adding fuel is only half the battle. If there is no computer upgrade, I'd say you can forget the forced induction idea....
     
  9. CyberSniper

    CyberSniper 1/2 ton status Premium Member

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    I figured he was going with a roots setup as it produces peak boost at around 1500rpm. You can only run 6-7lbs before you need an aftercooler with roots and especially with high compression. Distributor recurve kits usually come with the blower kit.

    It's too early in the morning to be thinking about this.
     
  10. Seventy4Blazer

    Seventy4Blazer 3/4 ton status

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    well on TBI the computer changes the timing as needed. an upgraded custom burnt chip would solve that problem.
    Grant
     
  11. K5er4Life

    K5er4Life 1/2 ton status

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    I would definitely have to say that a TBI would not be able to support a forced induction. Im running a 670 cfm holley TBI on my 383 that is pretty mild and I had to do quite a bit of chip tuning to get it to run right. You might be able to get the holley 4 barrel 1000cfm and get that to run with forced induction, and that TBI comes with the ecm and everything you need to get it going.
     
  12. u2slow

    u2slow 1/2 ton status

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  13. Thunder

    Thunder 3/4 ton status

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    I know Weiland and Vortech, make a supercharger Kits for late model TBI trucks made 1989 and up. They include Chips,Fuelpump, pressure regulator and everything you need. They bolt right up to 5.7L (350) and 7.4L (454) trucks with serpentine belts.
    Because they use higher fuel pressure you dont need to change injectors.
    They are good for around 60-75 HP.
    Superchargers are kind of an expensive way to get 75 Hp. You can do that for a lot less $$$ with Heads, intake, and cam, and stay NA.
     
  14. fad2blk99

    fad2blk99 1/2 ton status

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    Yeah that customburned chip sounds like a good idea... /forums/images/graemlins/deal.gif but I've yet to hear of anyone who has had success with that; not to mention the $400-500 price tag on those babies....
    Let me know if your heard different, cuz I'd like to believe I can stroke my 350, run some vortecs and RV/4x4 cam and not have it run like total [crap]. /forums/images/graemlins/ears.gif /forums/images/graemlins/ears.gif /forums/images/graemlins/ears.gif
     
  15. Thunder

    Thunder 3/4 ton status

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    These guys can build just about any kind of chip you want
    http://www.fastchip.com
    They have a lot of experience with custom 350 FI chips. getting one to run with a mild 350 like you described is no problem as long as it is NA.
     
  16. fad2blk99

    fad2blk99 1/2 ton status

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    Thanks for the link; the site looks pretty goood.
    Have you had any experiance w/ them personally?

    [ QUOTE ]
    ...as long as it is NA.

    [/ QUOTE ]
    /forums/images/graemlins/confused.gif What do mean by "NA"? /forums/images/graemlins/confused.gif
     
  17. Thunder

    Thunder 3/4 ton status

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    I have one of their stage one chips in my K5. I like it ok.
    I had them burn a chip for a mild performance TBI engine I built for a buddy. It runs great.
    Faschip has a pretty extensive data base for building custom chips. They can usually get it right The first time if you use common performance mods. They will work with you for custom aplications.

    NA= normaly aspirated (no blower, turbo, or N02)
     
  18. K5er4Life

    K5er4Life 1/2 ton status

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    [ QUOTE ]
    Yeah that customburned chip sounds like a good idea... /forums/images/graemlins/deal.gif but I've yet to hear of anyone who has had success with that; not to mention the $400-500 price tag on those babies....
    Let me know if your heard different, cuz I'd like to believe I can stroke my 350, run some vortecs and RV/4x4 cam and not have it run like total [crap]. /forums/images/graemlins/ears.gif /forums/images/graemlins/ears.gif /forums/images/graemlins/ears.gif

    [/ QUOTE ]


    A customburned chip is pretty cheap if you go to TBIchips.com, (mine was 50 dollars /forums/images/graemlins/peace.gif) Brian is real helpful and did my chip only once, sometimes you may have to send the chip back to get reprogrammed, and with using the WinALDL you can finely tune it. The problem is in order to get a good a chip for your motor you would have to program and tune the chip yourself, or have someone that knows how to do it. www.thirgen.org has alot of good info of TBI and about chip burning. I am running a 383 with sr torquer heads, 2.02/1.60 valves, and a holley 670 with their pro-jection manifold, you cannot run a RV cam with TBI, it is way too much for it. Really probably the biggest cam you can run without having to worry about alot of chip hassles is to run about 210/216 @.050 and .454"/.440" lift, this is a compucam 2040 and thats also in my 383, has a strong idle, no lope but a mongo amount of torque at idle /forums/images/graemlins/woot.gif. I love my setup, it been running great for the last 7500 miles with no signs of slowing. /forums/images/graemlins/k5.gif
     
  19. skratch

    skratch 1/2 ton status

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    [ QUOTE ]
    you cannot run a RV cam with TBI

    [/ QUOTE ]

    Um yes you can, I have one in my Burb.
    There are different RV cams out there and over the past several years more and more of them have been ground so that they can be run with a TBI engine. I got mine from Jasper when I bought my new engine a few years ago.
    She has a lot more grunt than the stock cam ever offered. /forums/images/graemlins/waytogo.gif
     
  20. 84_Chevy_K10

    84_Chevy_K10 Banned

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    The Comp "RV" cam has a very tight lobe seperation which would drive a map sensor NUTS.

    Everyone has a differing opinion to what an "RV" cam is, but all the specs for the ones I have seen were low enough duration but the other specs didn't seem like they'd jive with TBI.
     

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