Originally Posted by Jeepstin12

I just moved from sea level. Run on e-470 every week. I didn't see an mpg drop, and not much difference in feel. Dyno? I'm sure you could see the change in numbers. I guess I feel, if I wanted HP and top end performance, I wouldn't have bought a jeep. Or, i wpuld have opted for the sweet SRT8. Not t mention, the peak HP and torque are at higher rpms than the vast majority of anybody actually drive at.

The numbers?
The old 3.8-liter V-6 produced 202 horsepower at 5,200 rpm and 237 pounds-feet of torque at 4,000 rpm. The new 3.6 puts out 285 hp at 6,400 rpm and 260 pounds-feet at 4,800 rpm.

The formula?
HP Loss = (elevation x 0.03 x horsepower @ sea level)/1000. That's about 45 HP from sea level to 5280'. That's at peak power (6400rpm). Considering whp at 189hp (assuming sea level), this variance is far less, reflecting 29.9xxxx horsepower loss. For a vehicle weighing at 5800 lbs., that's a realistic yet negligible difference. In this entire mix, torque gets you moving. Horsepower keeps you moving.

Under normal acceleration, you may hit these rpms. Trail? Rarely. There is no argument to be had when numbers are there.

I'm an engineer, prosthetists and a bio mechanist. How are those physics for ya? I believe I now earned the smart ass badge.

Originally Posted by zstairlessone

Don't really sit at peak all day in the mountains. Remember that loss affects the entire RPM range and any HP (torque) loss at those lower numbers creates a notable change. I moved from sea level up to 8500' in northwestern Colorado and my sport bike had a real hard time pulling the front wheel on the throttle in first (couldn't do it at all in second up there even with help). At sea level first and second would slap my face with the speedo (hunched over the tank) on the throttle it would come up so fast. The HP loss was VERY noticeable - at least to me - at altitude.

Originally Posted by RIPPMODS

For our customers at altitude, we have a "high altitude pulley" that allows for the blower to be sun faster, making more boost, so the power losses with our system are negligible. We have had our system tested to over 13,000 FT with excellent results.

RIPP

Originally Posted by blackop4hire

How easy is it to swap that pully if we're going back to lower elevations near sea level or will it not need to be swapped?

EOD

Originally Posted by RIPPMODS

Will not be necessary, calibrations loaded will already account for it.

RIPP