How to Increase Velocity???

[Rockrz]

I'm looking for the best (and cost efficient if possible) way to increase air intake velocity at the throttle body of a late model LS V8 engine.

I see there are companies that have specially designed throttle bodies (like the JET Powr-Flo Throttle Body) that have dyno proof that their throttle body increases air velocity... If anyone know of companies other than Jet to look at for this, please let me know.

Another option I've seen is throttle body spacers which should do the same thing to increase incoming air velocity even though they sit behind the throttle body.

Anybody have any recommendations for a good spacer that increases velocity?

Just wanted to get some recommendations from those that have done what I'm looking to do... increase incoming air velocity - Thanks!

[Rockrz]

And, the folks at Jet claim their JET Powr-Flo Mass Air Sensor provides "airlow increases of up to 45%".... can a mass air sensor do this?

If so, are there any other options other than Jet to consider?

[Eaglegoat]

Why are you looking to increase the velocity of the air moving through the throttle body?

[Bill@HPTuners]

Superchargers increase the velocity a bit ;-)

[Rockrz]

Why are you looking to increase the velocity of the air moving through the throttle body?

There is dyno testing that shows this sort of thing can provide 10 to 15 extra horses

Superchargers increase the velocity a bit ;-)

I didn't want to spend quite that much... my wife would put me in time out!

[Markmx6]

Honestly in my opinion Port velocity and combustion chamber atomization would give bigger improvements. I think the velocity is actually a byproduct or easier way of measuring what is causing the real improvement, which is more air at the same RPM.

There are multiple ways of doing that, The cheapest would be lowering your intake temperatures...Then your velocity is the same but there is more air due to a denser charge...

Sorry, you got me thinking and I tend to ramble...

[Rockrz]

I agree, but I'm not wanting to go to the expense of pulling the heads and having them ported.

My objective here is to increase horse power and efficiency as much as possible without spending a bunch of money.

the engine only has 14k on it, so I just want it to run better and be more efficient without breaking the bank by doing a few bolt on mods before taking it in for a tune.

[jimmyblue]

At a single orifice point you only get to trade velocity
(flow) for pressure drop while the mass flow is set by
the whole chain. Increasing velocity this way (by
less orifice diameter) is a losing proposition as you
go higher in flow.

"There is dyno testing that shows this sort of thing can
provide 10 to 15 extra horses"

Yeah. Sure. This kind of thing is all over the automotive
aftermarket. Rarely is it coming from someone who isn't
selling soap. If you can prove it to yourself, swell. Not
to be relied upon, if it's from the vendor's promo material.
5-10 HP is within the range of normal variation and you
can cherry pick so easily.

[Rockrz]

There are some independent shops that have done dyno testing and have found an increase in horse power to the rear wheels and this using the type of dyno machine that bolts directly to your rear hubs.

[Markmx6]

While that is true that there may be an increase, at what RPM? I would imagine that the port velocity improvement would be at the top of the band which provides you with virtually no benefit and may in fact hurt your low RPM torque.. In my opinion 5 hp at 1600 rpms is worth more to me than 45 hp at 5500 rpms. It would be more important to me to gain every bit of torque that I could and as much of it in the 1000-2000 rpm range where I spend most of my driving.

I totally get the low cost improvements and I still recommend lowering your intake charge temperature as this will allow you to have a denser mixture with more fuel and also probably allow for some more timing without knock. A free flowing exhaust is also a good option, although not as cheap...

I wasn't suggesting pulling the heads and porting, but maybe another intake manifold? That may offer some gains depending on your goals.

[Rockrz]

I still recommend lowering your intake charge temperature

How is this accomplished? By installing a different intake manifold?

My vehicle is an '09 Chevy Colorado with 5.3L so if you know of a good bolt on intake manifold that would be beneficial, please let me know.

[Markmx6]

To be honest, I am still working on that with my own truck. My 2002 silverado seems to get a lot of air from the radiator running across the intake tract which heats the air up (up to 20 degrees over ambient) measured from Hptuners and an infrared heat gun. I'm also open to suggestions

I haven't done the intake manifold because I am still saving for a 6.0 to build up, and it seems like a waste to put a manifold on a stock 4.8...

[Rockrz]

Well, I'm probably going to just go with the Jet Powr-Flo Throttle Body for a slight bump in velocity which includes updated electronics for quicker throttle response than stock, a Volant Cold Air Intake and take it in for a good tuning. If they guy thinks wide band 02 sensors would help I may do that.

I just want the best efficiency and power I can get without... you know, building a new engine

But, if I win the lottery... all bets are off! I'll be building several kickin rides!