ammoman

...which would you rather use: a larger [id] throttle body, or a helix-bore TB spacer with a stock TB. Of course the two together would be ideal, but of the two separate, which would be "better" overall?

What are the pros/cons to either? Which is better- more air in, or "forced/spun" air?

Spend the moolah on the larger-bore setup, or be thrifty and get a spacer?

Opinions? Facts?

Veniston

The air spinners have been pretty much debunked as crap. Even aside the other arguments--how is the air going to keep swirling after it passes by the throttle plate? That pretty nicely divides the air flow. And if it were as easy as adding a small fan to 'force' air in, people would be using 20 dollar CPU fans instead of spending $$$thousands on super- & turbochargers.

Unfortunately if you want real performance, you've got to pay for it wink

Random

I think Ammoman is refering to a Throttle body spacer that would "swirl" the air after the TB.

In my personal opinion, swirling the air in the intake manifold has little/no benefit. I would say extrude hone your intake manifold rather than install a helix/swirl spacer between the TB/IM.

Between the choice of a larger TB or Extrude honed intake manifold...we don't have any dyno tests to prove it, but I would go for the Extrude Hone'd Intake manifold...

ammoman

Veniston: I am referring to a spacer , not that SpiralMax or Tornado crap; I've been around long enough, and have learned enough, to know those don't work as advertised. wink

Thx for the input, Random. My question stemmed mostly from the fact that the TB spacers do show an improvement, but the only data I've seen on them are for larger displacement 6 and 8 cyl (like the 5.4l on my Expedition). I'm curious as to how they'd perform on the smaller 4's.

I was wondering which of the bolt-on mods would be "better" until I could find a reliable machine shop to do the internal work on the IM.

MAXXTIB

What I would do is first bypass the cooling lines going to the stock TB, this will cool down the incoming air a little. After that go with a plastic spacer to help insulate it from the heat a little more. If you can't find or make a plastic spacer I have seen a lot of people use 1/2" plywood to make their spacers because wood has a higher insulating factor than other materials but it doesnt last as long. then bore out the intake and upgrade to a larger throttle body when you can.

Random

I would NOT reccomend plywood as a spacer. Gasoline and oil will break down the plywood rather quickly. Your engine is then going to start injesting bits and pieces of wood. The wood will also absorb the gas/oil and swell...and the gas/oil soaked plywood is a HUGE fire hazzard.

I've got a guy working on an intake manifold spacer made out of a plastic material that is heat and petrolium product resistant. It will only be about 7mm thick, but it should help. We can't go any thicker unless people are willing to replace the studs that hold the IM on...which I assumed most people are NOT willing to do. Also the IM has 2 bolts in back of it attaching it to a brace. I'm not 100% sure that we will be able to attach the IM to the brace once this 7mm spacer is installed. As soon as I get the first unit...I'll let you guys know how it goes.

Veniston

Alright, alright, I actually did a bit of poking around, and they are different. Found a few sites selling them (dunno if there's one for the BETA's tho), read one person's review of an install on a Jeep--and he said it was the most useless mod he'd ever done. He was so annoyed with it that he actually paid to return it, and with the initial delivery charge it came to a higher cost than it was worth.

Another site claimed "a friend knew someone who dynoed it" for a 2 hp gain. Nothing like first-hand facts, eh?

I can see how directional air-flow control could aid in the intake manifold--but have you looked inside your IM? It's pretty rough, not great for flow-pattern development; as Random said you'd need it polished or honed before any decent effect could be felt.