OR is it.... The fact that knowing it's there..... Makes you unconsciously more aware of what's going on....and you end up beliving just enough that your truck feels just that much faster? Happens all the time....

 

Plenum volume does matter on a 5.7 Hemi
as can be seen if you go to the end of this article
by Steve Dulcich in Mopar Muscle:

http://www.moparmusclemagazine.com/t...kes/index.html

where he shows his friend Richard Holdener
adding different length spacers to explore the plenum volume effects.
Unfortunately the article does not tell us what they found that day in detail.
Keep in mind that they have already changed out the factory intake manifold and fly by wire throttle body...so they are investigating plenum volume effects on aftermarket stuff that has MUCH lower plenum volume than the factory parts.

Also keep in mind that when you open your throttle body butterfly all the way the plenum volume expands to include the volume in your air intake tube and air filter box. This does not happen at part throttle. Volumes matter.

 

Duso02 - thanks for putting it into "understandable" terms.
Now that was a bit easier.
For the aspect of a lot of talk that's coming out, it's interesting to hear that some say that your 'mind' will tend to think now it's working just because of whatever issue. Haha. I guess now when it comes to throttle body spacers it's a matter of mind over matter and we're just hitting all sorts of topics.Noticed that.

Interestingly enough the statement of how people would say throttle body spacers don't work without experience is quite ignorant and stupid. I think we're back in jr. high where "he said it doesn't so it isn't". Sigh. I'd rather go with the psychological diagnosis of the thought that I thought it works because I want it to work rather than kids talking of how it doesn't work because "my good buddy said so".

I haven't dyno'd my throttle body spacer, and for those who have said they have with one and noticed zerodifference. . . I guess I have nothing to say about the 'facts'.and maybe we can conclude that I am just thinking it does making me believe it does.

 

It would be a great step forward
if owners who installed throttle bodies
would at least use the stop watches built into their cell phones
to check before and after the throttle body installation
whether their vehicles accelerate faster
from 30 to 70 mph.

My prediction would be that there would be almost no improvement
simply because Chrysler engineers have already made the plenum volume very big from the factory.

 

HankL- Haha ok I think the concept of the throttle body spacer might not be seen by simply taking school-boy stop watches and try to clock times. I think more in the essence of MPG, saving gas. I think the concept of how the throttle body spacer works isn't for the 0-60 stuff, but simply the addition of helping out MPG. I read more reviews and people who can see the change have seen that there has been a change of .2-.5 MPG. Others have said a 1-2 mpg gain. Just saing that I don't think I'm here because I think throttle body spacers will make the difference between the seconds, or the win or lose in a race, just simply the MPG.

 

A spacer works great on throttle body injected vehicles. Too bad those are from 15+ years ago. In those instances it helps the fuel & air mix and makes a very noticable increase, esp. in low end torque.

On today's trucks? Nothing. Seriously -- if you could improve mpg even by a tenth, don't you think it would have been designed in from the factory? They work so hard on mpg gains that a simple spacer would have been used long ago.

 

Well that poses a good question. Why wouldn't they add/design it in today's trucks? Maybe because thats what the aftermarket products are for? I mean think about it, if they are squeezing out MPG as much as possible anyways and you're wondering why they wouldn't throw in an aftermarket product, why don't they just throw in a superchips tuner in the glovebox of ever vehicle, OR they could just calibrate it already into the vehicle to optimize the best MPG/HP gains. I'm kinda lost with that statement.

This post has been very interesting. Lots of negative remarks, some positive and i've looked elsewhere to find some people really think that it makes a difference. Thats all I have to say about that..

 

My thoughts on TB spacers, I have one in ('03 4.7), I put it in the same time as my K&N CAI, and I noticed a close to a 1 mpg improvement and a very nice increase in torque. Going up hills that I used to have to downshift to 4th or 3rd (I have a 5sp manual) I can now make it up in 5th or 4th. I don't know if that's from the CAI and the spacer isn't doing anything or not, I'm not all that inclined to take it out, go somewhere and test it. But when I know I'm going somewhere where I'll have the chance to test, I do plan on bringing tools and removing the spacer to see what happens. But for now it stays in.

 

Anyone have one of these paperweights they want to sell???????????????????????????

 

I haven't got my truck back yet. They keep saying they are getting the wrong parts. The day I get it I will install the tbs and I will let you guys know what I thing if it works it works if not #*&% it. I will have this neat little red thing at the end of my intake. Thanx everyone for ur input.