What's the general feeling on throttle body spacers on newer 5.3/genIII engines? Any gains to be had by the one that claim to induce some kind of swirling effect in the throttle body bore? Looks like an easy mod if there's anything to be gained.

 

In my opinion it's a scam. The swirling of air through a spacer does not increase air molecules or compress the air any further (like boost), so it results in 0 HP. The reason to have one of these is to custom fit an intake as some other board members will describe. This products is like that "Tornado" trash that swirls air for 30 more HP and better gas mileage. It's all bull. Besides, if it's that great, why didn't it come OEM?
Philip S.

 

Emissions legal headers are great, and they don't come OEM. Just a thought. I don't know if they are the best mod in the world, but for the price, I like them. We recently installed one on my buddies 4.3 S10 and it seemed to perk it up a bit.

 

Emission legal headers cost more for the manufacturer to produce and produce a lot more heat into the engine bay. This can cause melted spark plug wires, and a hot cab of a truck. I know their are various heat coatings, but price is the main reason . The only theory I can think of behind a throttle body spacer is the venturi effect. It could speed the air up increasing VE, but that's hard for me to belive because of the "swirl" effect and other variables. Also, your mind can also play a role in performance. You know how you meet those people who say when they put 93 octane in their tank (when 87 is fine) they say there truck, car, lawnmower, etc. is more peppier? I know I've met quite a few. After you install a product, you want it to work just for the sake of not "wasting" money. Not flaming at all, just giving my opinion
Philip S.

 

My uneducated theory on why they dont work is how could 8 intake runners that are sucking in air through 1 hole in the intake manifold (search for pics of a cut open truck manifold) be affected by any kind of 'spiraling' air? Once the air hits that upward turn into the manifold its going to get 'torn apart' by the intake ports, at least thats how I see it.

When they do the little bottle trick on tv and show how swirling water moves quicker between the bottle.....that has little relation to 8 or 6 or whatever intake ports sucking in air from one source, again this is my uneducated opinion.

Another reason I dont like them is that If I were to use one with my Volant, I'd have to notch the fan shroud to get it all to fit because it would stick out 1.5 inches more and it would make it even harder to get that intake tube on the t/b

 

I thought tb spacers were pretty much considered paper weights. Them being used as an interface for a different intake manifold makes sense.
What 03 GMC said about what happens when the air hits the runners makes sense. How about when the air makes the 90 degree turn to enter the tb?

 

wont a "swiral" slow the air speed down???????

 

I agree with 03GMC and cupholder. As cupholder said. The TB spacers have little swirl slots. Basically a square with a coiled spring milled into the square. If the air travels over the ruts from going from the smooth part of the TB spacer to the swirl design, the air would have to change direction. In fact, with our engine's drawing in roughly 500 CFM of air flow, the air isn't going to take a roller coaster ride on the TB spacer, it will bump in the the swirl rut, bounce in the air and "collide" with the other air causing somewhat air resistance. And as 03GMC said, probably the #1,2 cylinders would receive this so called "swirled air". At this forum we should have more discussion like this on each product. Geeze LS1tech.com is a great website! Lots of smart people!
Philip S.

 

and to add to it, the truck manifold isnt just an open chamber where the first runners would get more air/spiral, but the air actually goes into another turn thats in the middle of the manifold (inside), this turn forces the air up to the top of the manifold and disperses (sp) to the intake runners. Unless I was looking at the cut open manifold pics wrong

 

paperweight!!!