Do throttle body spacers really work?

[TerryMason]

I've heard alot about throttle body spacers over the years, but I'm not sure I understand or believe alot of it.

Unless the factory installed a spacer in there that was purposley restricting airflow I don't see how raising the trottle body up 1/2 inch would help. The "cyclone" thing just sounds like marketing talk to me.

Am I way off? Would a throttle body spacer do anything for my 4.0?

	Throttle body spacer A throttle body spacer is designed to improve the quality of the airflow, allowing air that is more condensed and, thus, more oxygen laden, to enter the combustion chamber. The result of this is a more efficient burn, which serves to release more energy from the fuel, making more horsepower available.

[Dry suit diver]

Originally Posted by TerryMason

I've heard alot about throttle body spacers over the years, but I'm not sure I understand or believe alot of it.

Unless the factory installed a spacer in there that was purposley restricting airflow I don't see how raising the trottle body up 1/2 inch would help. The "cyclone" thing just sounds like marketing talk to me.

Am I way off? Would a throttle body spacer do anything for my 4.0?

some 4 litre owners over here have reported better oomph when accelerating but that may be the placebo effect. the only true way to test is get it on a dyno.


or write to myth busters

	Throttle body spacer A throttle body spacer is designed to improve the quality of the airflow, allowing air that is more condensed and, thus, more oxygen laden, to enter the combustion chamber. The result of this is a more efficient burn, which serves to release more energy from the fuel, making more horsepower available.

[Bounty__Hunter]

I think they work, and most are 1" tall.

The biggest improvement is from 62mm throttle bodies, which I happen to sell, cheap. I use one on my 2.5L in conjunction with a 62mm spacer.

[jeepster357]

I use the Airaid cold air intake along with the Throttle body spacer, I cant quote you numbers but judging from my seat dyno (seat of my pants) my 4.0 does seem to have more oomph. I have noticed haveing to down shift less on steep grades and I did gain around 1-2 mpg's. And there is a added bonus of a little bit of a "growl" that comes from the air intake. cool.

	Throttle body spacer A throttle body spacer is designed to improve the quality of the airflow, allowing air that is more condensed and, thus, more oxygen laden, to enter the combustion chamber. The result of this is a more efficient burn, which serves to release more energy from the fuel, making more horsepower available.

[Heydace]

They do work, you may feel a slight difference (or not). The theory behind them is that they atomize fuel molecules better than the stock t-bore and intake. I would opt for a larger t-bore and air intake system (K&N or similiar) then open up the exhaust to allow for the increase in air intake. You want a smooth flow of air in and exhaust out.

[TerryMason]

I can understand a cold air intake making a difference, but I haven't bought into the spacer yet.

For $5 Chrysler could make these parts themselves. If they really did give a 1 mpg fuel savings, that would be a 7% fuel savings - why wouldn't Chrysler want this?

I'm gonna go ahead and buy one and put my money where my mouth is. I've kept great milage records to date, so I'll let everyone know what I find out.

[jeepster357]

When I installed my TBS it was in conjunction with the new intake so I cannot vouche for the TBS as a stand alone upgrade. I do know my mileage and performance has increased slightly over stock though.

[PA-XJ2]

hey, i think they work i had one on my 90 XJ (renix motor) and i could def notice a difference on take off.
-Ant

[Bounty__Hunter]

Terry, any update?

[TerryMason]

I've got the spacer, but with all this good fishing weather, I haven't had time to install it.

[Bounty__Hunter]

Keep in mind that power and mileage may improve over the course of a week or two after install, giving the computer time to adjust to the change.