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tbi modification

Discussion in 'The Garage' started by bad_bo_ti, May 1, 2003.

  1. bad_bo_ti

    bad_bo_ti 1/2 ton status

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    i am getting a 454 throttle body soon and am wanting to modify it some, i have seen some where but forget where on how people have ported/polished them and other thing they have done, does anyone have a website on how to do this. i am also getting another intake so i can bore it to match the 454, it should liven up the ole 350 /forums/images/graemlins/thumb.gif
     
  2. mosesburb

    mosesburb For Rent Premium Member GMOTM Winner

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    Just a note to let you know something I found out a couple years ago. The '94-'95 454's use a different fuel pressure regulator and injectors than the earlier ones use. The 94-95 are designed to run on (as I recall) 32-35 psi, whereas the earlier ones run on the typical 9-13psi. If you scored a later one with the higher press regulator you will need to swap your in-tank pump for a 94-95 454 pump. The p/n's for the injectors changed in 94, but I don't know what changed about them. The swap of the fuel pump is no biggie as the pumps are interchangeable and a power increase should be expected. If you got an 87-93, you'll be good-to-go with the same small block pump you have already. Let me know if you want help with part numbers (it's what I do) Good Luck, Nick
     
  3. bad_bo_ti

    bad_bo_ti 1/2 ton status

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    if it is off a 94-95 why couldnt i just put a fuel regulator on it? or put my 350 injector pod on it? would i still get a noticeable difference? thanks, chris
     
  4. mosesburb

    mosesburb For Rent Premium Member GMOTM Winner

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    The 454 injector part numbers changed in 94. I haven't been able to find out what changed about them, but they did get a new number(I am assuming that the change had something to do with the higher fuel pressure). The regulator will bolt up, but I don't know if you will acheive max H/P with lower fuel pressure going through injectors designed for higher fuel pressure. As for installing your 350 injector pod, I do believe it will bolt up, but once again I am not sure if max H/P can be acheived with large throttle body bores and small injectors. I am wondering if going at it with the small injectors will create a lean running condition. I guess it wouldn't hurt anything to try your different parts and see what happens. Good luck /forums/images/graemlins/grin.gif
     
  5. Hardcore

    Hardcore 1/2 ton status

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    I'm a little new to the GM TBI

    I just bought a 1990 K5 with a 350

    Can I just get a 454 TB and bolt it up to my 350 and get a little more power. I've been looking at the one from Arizona Marine. Want to get a little more power out of my stock 350 /forums/images/graemlins/1zhelp.gif
     
  6. bad_bo_ti

    bad_bo_ti 1/2 ton status

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    to bolt a 454 t.b. to a 350 intake the intake holes have to be bored out the same as the 454, the bore on the 454 are bigger than the 350. if your looking for some cheap tricks to get power, i would recommend a 160 thermostate, open element air filter and try to score a set of undrive pulles off ebay for cheap. these are all thing i have to my 350, havent got the 454 t.b. installed yet but there is a noticeable difference with what i have done so far. hope this helps /forums/images/graemlins/thumb.gif
     
  7. Hardcore

    Hardcore 1/2 ton status

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    Which air filters bolt to TBI's, I'd like to get the 14" round style about 3-4" tall. I know the ones for cards fit on Dodge TB's, do they fit on GM TBI units or do I need a special base?

    Is the 454 TB a direct swap, assuming I get a 87-93 one like mosesburb said?
     
  8. bad_bo_ti

    bad_bo_ti 1/2 ton status

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    any air filter will fit, i bought a used k&n housing and elment off my buddy, the onyl thing is, mine had the dual post hold down for the lid, your might not, but if it does you can get a a post off a single post and it will bolt on the the throttle body, the 454 t.b. will still have a bigger bore than the 350 intake so the butterflies wont open, one thing i thought of so i dont have to tear the intake off is to get a spacer made that has the opening for the 454 on one side and tapers down to the 350 opening but the might make it to restrictive. i think i have also heard something about the t.p.s. (throttle position sensor) that they are either different or the plugs are different on them, i forget what it is though, hopeffully some one can answer that one for. hope this helps
     
  9. 90K5

    90K5 1/2 ton status

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    if anyone wants to score some underdrive pullies...i got a set for sale off my 350 TBI...PM me
     

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