Thought it was interesting that they saw no gains with a larger throttle body...

 

I would tend to bet there would even be a lose of torque initially due to loosing intake/port velocity due to the larger body.

 

Perhaps... when most people post about modding a 4.0 a larger throttle body is one of the first things generally suggested. Guess I won't waste my money on one..

 

my 63mm tb makes it rev smoother when it's colder outside. i can't put a hp figure on it, but as long as i've been driving my XJ, i can tell a difference before and after. also, they might just try to discourage you from other mods so that you just buy their product.

 

This is the second time I'm having to correct you on this subject. That second sentence is completely untrue. A rotary lobe or twin screw design would require "RPM" to produce positive pressure just the same and any of them could be assembled to produce different amounts of boost at different RPM's. It's all about the pulley ratio, relative to the crank, the size of the blower and the pressure desired. Not to mention you can actually set a centrifugal unit to produce air sooner by utilizing a bypass valve to bleed off excessive pressure; not easily done with a manifold based unit. THE ONLY commonality between the two is the venturi snail shape and the use of an impeller. A turbo has an exponential growth of air production, regulated by a wastegate, where a supercharger has linear growth based completely on the RPM supplied. Trust me on this, I design air assisted agricultural sprayers and use centrifugal and rotary lobe units on a daily basis.


The main reason's I would choose a centrigual unit are as follows:
1) size a freedom of placement
2) no modification required to intake plenum
3) easily plumbed to a heat exchanger

 

To me, a turbo/supercharger is pointless on a offroad vehicle. What, after wheelin' you gonna take it by the drag strip and make a pass?.. In my experience, the more horsepower you got, the easier it is to get stuck. Though, you want enough horsepower to turn over and clean the tires, but not so much that all it wants to do is spin so damn fast and easily it just digs itself a hole. A good running 4.0 and the right gears is plenty enough power for anything in the woods in my opinion.

 

http://www.youtube.com/watch?v=http:...layer_embedded


well, why not?

 

I can call BS on the big bore throttle body. I have a 99 intake and APN header on mine, and putting a 62mm throttle body on it makes a WORLD of difference, I mean night an day as far as acceleration. And I don't seem to have lost even a little bit of bottom end torque. With a restricive exhaust and intake though I'd imagine it doesn't make as much of a difference.

 

http://www.superchargersonline.com/content.asp?id=5
Your wrong..
Roots/Whipple charger is the best way to go for a instant throttle response and low rpm torque.
Your not correcting anything.
I won't touch this again.

 

Exactly how am I wrong? I can easily set up a centrifugal unit to produce, say 5psi @ idle, I guess if you wanted to, and exceed the 12-15 psi limit of rotary lobe unit and still have cooler air with less HP consumption from the engine. Either way, THEY'RE BOTH POSITIVE DISPLACEMENT AIR PUMPS!

I've said nothing but correct information this entire time.