When reading through this thread: viewtopic.php?f=51&t=4823 It made me think, "Why Guess?" If anyone has the HP and Torque curves for our 3.7 engines, it should be easy to figure out the most efficient RPM range. So who's got them? I tried searching, because I thought I had seen them here before, but failed in my search.

Yes, I know that you have to take into account drive train gearing, but you gotta start at the engine.

_________________
2007 Light Khaki 4x2 Sport
- Debadged - LTT CAI with Amsoil Filter - JVC HD Radio - Infinity BassLink
- Iggee Seat Covers - Black Moabs - 265/75-16 Cooper Discoverer ATP - 4.10's
- DIY Franky sitting at 23.75" - Al's 4.5 UCAs - Trimmed F&R Bumpers
- Removed Rear Sway Bar - Removed Rear Vibration Damper
- 75k miles so far...

most dynos don't start fully recording information until after 2,000 rpm the torque peak stops the initial sharp increase and levels off to gradual at about 2700 RPM

at 2700 RPM, stock you're making about 1/3rd at best of your overall HP

4000 - 4300 is the worst performing range of the engine, which many drivers notice the engine literally stumbles through that range of RPMs, for whatever reason at this range the stock 3.7 hp curve stops the ramp increase and drops ~25hp and ~40 ft/lbs tq. for 100-150 RPM then re-increases

for the most part, you've milked your efficient torque by 2600 with the least amount of throttle

i've got a really crumpled copy of my stock dynos, the rest of my dyno sheets are somewhere in the file cabinet at my other house

_________________
03 Renegade (Black)
177k miles 3.7L gas - 45RFE
Command Trac / 4.10s
Lift: ft. 790+ rr. JBA4+
The last of the TrailReady Front&Rear Bumpers and TR Rock Rails
Jarhead Offroad light covers
31x10.5R15 RedLetter Grabbers on Blackrock Dunes
L.O.S.T #KD098632

_________________
07 Sport 4x4
235/70-16 Wild Country XTX

MBRP has a before and after exhaust install dyno run at ...

http://www.mbrp.com/?page=dynopop&part=S5510&yt2=

it was run in 2008 on an '07 model year KJ. Real world rear wheel gains, seems legit.

_________________
Ian

2005 KJ Renegade, ARB'd, OME'd, Rancho'd, Warn'd, skid'd, JBA 4.5s, Cragar Soft 8s, GY MTs 31x10.5x15, and dirty, can't forget the dirty.