Any one have experience with throttle body risers? I have a 97 GC Laredo 4.0L and am thinking of installing one.

They claim improved fuel economy and increased HP. Is that for real or just hype?

 

I have heard yes and no from people that have installed them. If i was going to try to get a little more fuel mileage, i would go the cold air intake route with a K&N.

 

if you get anything from it, it will be an annoying whistling sound. thats about all they are good for.

 

They are worth about as much as a drop in K&N filter... Nothing.

 

They are only good if you have the newer intake manifold 98-2001 (XJ) AND have a bored TB.

Otherwise its just a shiny hunk of metal you over paid for.

 

what will they do for you if you have both? just wondering...

 

It just gives the air farther to travel before it gets to the engine. A throttle body spacer will do more good on a TBI (throttle body injected) vehicle rather than a direct injected vehicle such as your Grand. Typically on a carbed or TBI vehicle the spacer gives the air and fuel a bit more time to atomize (good thing) before reaching the engine. A bored throttle body will do you more good by allowing more air into the engine.

 

Throttle body spacers are for marks.

 

My 92 already had one installed. I removed it and experienced no change in MPG. Yet there was a slight performance decrease in the 2500-3000 RPM range.

My biggest boost in MPG came from a can of SeaFoam.

 

So, you felt this "slight performance decrease" in your butt. You must have the world's most sensitive bottom. Impress me and tell me you found out about this decrease on a dyno; otherwise, blah...

The biggest increase in MPG comes from the ever overlooked driver's mod.