TBI 40HP upgrade kit. Has anyone heard of or done this?

Discussion in 'Chevy C/K Truck Forum' started by Crispyt, May 8, 2012.

  1. Crispyt

    Crispyt Rockstar 100 Posts

    Irecentl came across this kit on the internet that clams you will gain about 40HP on your TBI engine. It has something to do with replacing your fuel pressure regulator spring with a different one and adding some kind of throttle body spacer. The link to the kit I found is listed below. Has anyone heard of or done this kind of thing before. Also is this bad to do, will it hurt anything in my fuel system? It says it mkes the system run at about 14psi with the upgade.

    Thank for your time and help all!

  2. Boonduff

    Boonduff Rockstar 4 Years 100 Posts

    I call BS. There's no way your gonna get 40 horses by just doing what they describe. You notice how they say up to 40 hp not you will get 40 hp.
  3. the phantom

    the phantom Epic Member 5+ Years ROTM Winner 1000 Posts

    I doubt you will get 40hp from this. Not to get to far off topic but why does everyone that buys something on ebay leave feedback for things like this before they even try it?! Or they just say great ebayer shipped quick blah blah blah. If the thing works like it says then leave the feedback saying that so future buyers know if its worth it or not. Ive learned my lesson.
  4. 4x4squared

    4x4squared Rockstar 100 Posts

    i had looked at those throttle body spacers for a 92 GMC 1/2 ton before because they claim to add HP and fuel mileage but looking at different reviews and talking to people that have them on their trucks/cars, it seems they dont do hardly anything. Unless that spring is going to give you 40 HP, i wouldnt bother with it.
  5. Strino78

    Strino78 Member

    Speaking as one of those guys that actually has these things under the hood - in my K1500 and my TransAm - they do help but they are not worth 40HP to a STOCK engine. Follow the 3rd generation F-body crowd around and familiarize yourselves with the inadequate Rochester 220 TBI systems the 305s and 350s were given as a stock platform. Frankly a lot of this stuff came from that crowd.. in search of lower quarter mile times. :D The cars and trucks shared a lot of the same tech, and it all applies. The ad isn't misleading. It just isn't disclosing to you that you should already have a cam, headers, full exhaust, cylinder head work... etc.

    The stock 220 TBI on a GM 305/350 flows 480cfm (42mm). The spacer increases cfms slightly by raising the pods out of the bores. This is the first step to optimizing the TBI, without doing any grinding or machining; which will further increase the TBI to a max of 46mm (600cfm)

    That spring is the fuel pressure regulator spring. Stock for a 305/350 is 12psi. Increasing the fuel pressure to 14psi (max for a stock pump), will allow it to flow similar to the 350 Police Interceptor injectors, which were "hotter". 55 lbs/hr vs 61 lbs/hr.

    You'll only see 40hp from these gains if you've upgraded a few other things, but they DO help stock setups. Its the next step after installing headers and a full exhaust. In short, adding more air and fuel after opening up the exhaust.

    Seriously, it's like the air filter and tuner ads... MORE POWER.. MORE POWER... UP TO 70HP by installing this.
    *You gained 70HP by installing that item on an engine that was built to the point that the stock component was the bottle neck.*
    1 person likes this.
  6. Enkeiavalanche

    Enkeiavalanche Loving the Outdoors Staff Member 5+ Years ROTM Winner 5000 Posts

    I have never heard of anyone liking a spacer.. Seen many Cons on it and No pros.....
  7. 4x4squared

    4x4squared Rockstar 100 Posts

    We need more guys posting like this lol I actually learned something today :D
  8. Strino78

    Strino78 Member

    It is an injector pod spacer not a TBI spacer there's a difference. There's distinct differences between spacing the injector pods and the whole TBI unit. Throttle Body spacers only work well on the older systems, and have little to no-effect on modern throttle body/multi-port/gdi injection systems .

    These are improvements for the older (pre-1996) TBI engines. Say what you want about them working or not... but they do work, and will work exceptionally well if the rest of your engine supports the additional air and fuel.

    I attribute all the negative feedback to people that dump money into performance parts without understanding how they work, and not having the supporting modifications to justify needing more air and fuel.
    Last edited: May 18, 2012
  9. 4x4squared

    4x4squared Rockstar 100 Posts

    I DID learn the difference... While reading your last post... Ty.......
  10. Strino78

    Strino78 Member

    I wasn't trying to talk down to anyone. I missed that sentence in proof reading. It is a broken/incorrect sentence fragment... my wording got muddled. I've edited the comment --- it wasn't what I intended to say... a parallel thought got jumbled into it.

    Sorry about that, and hopefully no hard feelings.
    Last edited: May 18, 2012
    Chesters likes this.

Share This Page

Newest Gallery Photos