Dyno Plots

[Root Moose]

I'm looking for a dyno plot/chart for a 2001 Cherokee 4.0. I thought I had one but it is the 2004 WJ 4.0:

It's probably the same for a 2001 but I'm interested in comparing if the curve has a different shape or not.

Let me know if you have one for 2001 or earlier or any other Jeep engine dyno plots for that matter. I can put them all together in a web page to share via my sig if there is interest. Or maybe a mod can sticky a thread with dyno plots.

 

[Dr. Dyno]

Here ya go:

 

[Root Moose]

Great, thanks!

I'm working on merging the 4.0, 4.7 V8 and Edelbrock head plot all into one plot via photoshop. It won't be accurate to real world but it will give the ability to compare curves I think.

I'll post it once I get it done.

 

[Root Moose]

Here's the 4.7 V8 in the 2004 WJ.

 

[Root Moose]

Here is the 4.0 I6 overlaid with the 4.7 V8 and the Edelbrock head for the 4.0 dyno in their advertising material.

I'm calling shenanigans by marketing on the Edelbrock dyno plot because the scale of the plot is messed up above 250 lb-ft. I'm assuming the next marker line is 275 lb-ft to match the rest of the plot and NOT 300 lb-ft.

Don't take the numbers on this plot as gospel - it's only accurate enough to show trends between the different engines. The numbers are likely +/- 5-10 hp depending on the day.

 

[yossarian19]

Thanks for doing that.
I'd love to see a 4.6 stroker in there but with so many build variables it'd be hard to pick a proto-engine

 

[Root Moose]

He's a quick and dirty of a stroker with peaks of ~270 hp, ~350 lb-ft and same shaped HP/TQ curves as with an Edelbrock head. Thinking very obtainable numbers...

Potential to destroy the stock ChryCo 4.7 V8. Can't speak to a built or HO 4.7. Is there much aftermarket for those engines? With those kinds of stroker numbers I really don't care about the V8 myself.

N.B. Only the stock 4.0 and 4.7 are real plots/numbers. The Edelbrock dyno plot needs to be verified. The stroker curve is extrapolated from the Edelbrock curve and a bit of selective speculation from stroker dyno plot examples given over the years.

 

[yossarian19]

I would be very curious to see what an Edelbrock head would do on an ATK Baja stroker. They claim 270 hp / 320 ft-lbs as they are selling them now. ATK's base stroker is in between the 4.0 and 4.7 performance wise.
A stock HO 4.7 is ~265 HP, 330 ft-lbs.
There isn't much of an after market for the 4.7 engine. Cold air intakes, cat-backs, programmers. That's about it. I haven't even seen camshafts for them.

I keep saying: if money was no object, I'd have bought a 6 cylinder WJ and put a stroker & built 42RE in it. As is, I'm quite happy with what the 4.7 is doing for me.

 

[Root Moose]

The idea of a six cylinder WJ has a lot of appeal to me also. It's a "real" Jeep engine (queue Willys/Kaiser purists spitting at Rambler). I never warmed up to Chrysler - they made nothing I've wanted other than a Jeep itself (WJ, TJ and earlier).

Too bad it wasn't straightforward to put the 545RFE behind the 4.0 in a WJ. Or swap in a manual transmission. All of these options are a pita with little gain though I guess. If you really wanted a 4.0 WJ that was built just build the 42RE and call it done.

 

[yossarian19]

I'm slowly warming up to Chrysler as I look at their V8s a little more carefully. I can't say the OHC 4.7 impresses me for horsepower but peak torque of 300 ft-lbs @ less than 3500 RPM is respectable in a truck or Jeep. I still prefer a pushrod motor for maintenance / packaging though.
The Hemi in a Magnum, 300, Charger or Challenger appeals pretty strongly as well. Crossfire wasn't bad, either.

 

[streetxj]

I wonder how much hp and torque my 96' 2-wheel drive automatic 4.0 XJ is making with my current mods. I'm going to add a chris-tuned ECU to my list soon.

Mod List:
180 degree thermostat
Newer style intake manifold from a 2003 jeep 4.0 engine
62mm throttlebody
Modified stock intake system with AFE Pro Dry S panel filter.
Bosch 703 fuel injectors
Gibson Stainless header (GP400s)
Dent/Pinch removed from stock 96' Cherokee 4.0 downpipe
2.5 inch Thunderbolt High Flow Catalytic Converter from performance-curve
2.5 inch Aero Turbine Muffler (AT2525)
2.25 inch dynomax tail pipe
Jegs Performance Ignition Coil
Taylor ThunderVolt 8.2mm spark plug wires with champion RC12LYC spark plugs
Accel cap and rotor

 

[Root Moose]

Go get a dyno done. I don't know about where you are but locally its only like $80 for a non-tuning session.

 

[streetxj]

Go get a dyno done. I don't know about where you are but locally its only like $80 for a non-tuning session.

I'll probably do that next winter when the weather is not hot and humid. I live in southeast florida. I'm wondering if someone here has a dyno simulator.

 

[Root Moose]

Do it anyway. +/- 5 HP doesn't matter.

 

[streetxj]

Will do. But for now, it's not going to happen. I'm going to be spending 325 bucks soon.