Throttle Body Spacers

Discussion in 'Performance & Fuel' started by MTM, Apr 3, 2012.

  1. MTM

    MTM New Member

    Okay I've been told so many different things on throttle body spacers. I want to know if anyone has put one on a 5.7 and what your pros and cons are
  2. Enkeiavalanche

    Enkeiavalanche Moderator

    I have never heard anything good about them..
  3. Jimmeh

    Jimmeh New Member

    I have one on my 4.8. All it did was give my truck a whistle. No power enhancements, no economy enhancements, nothing. If I had paid for it, I would be more disappointed, but I got it in a package deal with a buddy of mine.
  4. Asphalt Animal

    Asphalt Animal New Member

    I once read on one of the CAI manufacturers web sites that if they don't make one to go along with their intake, it doesn't do anything to enhance performance, and isn't of any use. They mentioned something about intake efficiency/volume.....

    I don't see much reason for them unless someone can show a dyno result proving that it works on that particular application.
  5. Jimmeh

    Jimmeh New Member

    Mine is the same brand as my CAI, which I can also tell you is pointless for a daily driver.
  6. moogvo

    moogvo Moderator

    They are a total waste of money. It's like standing on a chair to get a closer look at the moon.
  7. SurrealOne

    SurrealOne Former Member

    ROFL - I love the analogy and am of the opinion that it's absolutely correct. Throttle body spacers are a bit like snake oil in that there's no compelling proof one way or another that they're good for anything other than draining your wallet. Caveat emptor.
  8. Jimmeh

    Jimmeh New Member

    I will suggest that if you do plan on standing on a chair to get a better look at our solar system, please choose a solid chair that does not rock or spin. Concussions are an evil mistress.
  9. MTM

    MTM New Member

    Exactly what i wanted to see. I'm tired of all the mixed opinions but all these so far are the same so pretty much answers my question.

    Only person I have talked to that like it was a friend that put one but his was a tbi not an sfi. Said it just gave him great throttle response
  10. CowsPatoot

    CowsPatoot New Member

    I am quoting the following from http://60degreev6.com/content.php/114-Throttle-Body-Spacer ...this is a site for a different engine than our trucks have, but the point is the same.

    Port injection

    The TB spacer is meant to keep the throttle body cooler, by separating it from the manifold using a phenolic material instead of metal. The misconception is that by adding space behind the TB, you are going to get more torque.


    The lowered temperature is fine, and is worthwhile (see TB coolant bypass), but the cost of a spacer and the remaining intake manifold temperature doesn't do a whole lot on its own. The performance myth with this device is that it allows more air in, or that it lengthens the runners, or anything else along these lines.

    The torque curve is dependent on a lot of things, but for the TB related part, its actually not even related. The plenum, while connected to the runners, aren't part of the runner equation. You would have to lengthen the runners themselves to do anything. Actually, even this doesn't seem to work from testing on a 3100 with 1" spacers between the lower and upper intake. You would likely have to change the volume of the runners much more than just extending them will do.

    Regardless, this has nothing to do with the plenum. The plenum volume is important to performance and the RPM range of the powerband, but the TB spacer isn't going to have any effect on this because its volume is minimal.

    The only real value to a Throttle Body spacer is for a NOS setup. You can drill a hold in the spacer for a NOS injector. It is easier to work with a separate piece for the nitrous injector, and it is easier to return the car to normal later.

    TBI, Carb

    Unlike the port injected manifolds, a spacer that goes under the carb or throttle body will help out for performance. The extra space will help the air fuel mixture atomize, which will burn more efficiently. The myth part is for the port injected motors only.
    1 person likes this.
  11. MTM

    MTM New Member

    Okay just another thing I'd like to throw out there for everyone to consider. This truck sees a decent amount of highway and it seems to me that with a cold air intake and a spacer at highway speeds you'd have to see an increase somewhere. I'm not by any means looking for a huge amount of power out of this or a huge amount in mileage increase.
  12. ejohnson03

    ejohnson03 New Member

    Added one as part of a total Engine Performance upgrade, so no specific changes or performance gains to directly link to the TB spacer.

    If you are going through the process of making upgrades as are listed below, then adding a couple bucks ain't no big deal.

    That's just my 2 cents worth...
  13. MTM

    MTM New Member

    Is there any difference between all the different brands of the spacers? Or are they pretty much all the same?
  14. moogvo

    moogvo Moderator

    Chair... Moon. It's as simple as that. Does it matter whether the chair is leather or wood. The end result will be the same. There are no magical bolt on products that are going to make any real difference in and of themselves. Your engine is nothing more in the end than a big air pump. You get more air in and more air out to make any additional power, period. Adding a spacer not only has no way of getting any more air into the system, but the laws of physics actually dictate that such a device would add length to the path of the air and therefore cause friction loss due to the additional surface area of the spacer... ESPECIALLY if it is one of those ones with threads cut into it to "twist the air". Hand one of those to a smoker and have him blow smoke through it. You will then see that the air is not spinning out the other side.

    But what about a cold air intake? You can bore a manhole sized hole in your intake and force gobs of air into the system, but if the air doesn't have the means to escape (out the exhaust) then your new and improved hole won't help you either. Think about a 5 inch fire hose hooked to a hydrant with 150 psi of force going in from the hydrant. Let's also suppose that you are running a length of 100 feet of 5 inch hose. With the other end of the hose open, you will only get about 135 psi at the other end because of the friction loss in the hose. Now, let's adapt it down and hook a garden hose to it. You will still get 135 psi, but you will have no volume. Instead of flowing 5 gallons per second, you are maxed out at 1 gallon per minute. Make sense?

    Your engine will only pull in as much air as it can get rid of.
    Last edited: Apr 4, 2012
  15. MTM

    MTM New Member

    Thanks for that write up that pretty much says it all. think ill look into some other things to mess with.
  16. mfleetwood

    mfleetwood Moderator

    Since you're looking around for something else to mess with and Tom did such a great job with the fire hose analogy, I'm thinking an exhaust will go nicely with your CAI...:glasses:.....maybe?
  17. SurrealOne

    SurrealOne Former Member

    There is no maybe about it ... if he chooses wisely. :) And yes, [MENTION=12002]moogvo[/MENTION] did one heck of a job with a stellar analogy; props to you, sir. :great:
  18. moogvo

    moogvo Moderator

    Wow! Thank you! I expected to get flamed over that. There are guys that swear by those things and they will fight you over it, but you can't argue with simple physics! LOL!
  19. SurrealOne

    SurrealOne Former Member

    My background is in engineering, so you got no argument from me. :)
  20. MTM

    MTM New Member

    I'm actually a college student in engineering so no it all makes since there's no argument here. And i do have an exhaust it's a 3 1/2'' down pipe back into a 5'' tip

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