What's better on hills: DWL or Pulse up, Glide down?

[Duffman]

Can you post a schematic or do you have a link to one elsewhere that you would be willing to share?

[monroe74]

duff: "Seems to be significant RPM creep over the last few years."

Maybe that's the issue. This Motor Trend review (http://www.motortrend.com/roadtests/...fications.html) says the '97 Cherokee peaked at 3000. Then again, it's hard to know who to trust, because a Motor Trend spec listing for the '95 model (http://www.motortrend.com/cars/1995/...ons/index.html) says 4000. The same 4 liter I-6.

But here (http://media.gm.com/division/chevrol...n/subspec2.htm) GM says the '96 Suburban peaked at 2800-3200. So that fits in with what you pointed out, that this parameter has changed in recent years. Suburbans are getting more like Hondas!

"I am very much out of touch with new vehicles"

The number of new Suburbans being sold is probably rapidly approaching zero, so it could be wise that you're paying no attention to them.

[monroe74]

johnny: "That wouldn't make a difference [re wideband sensor]"

I wonder if you could help me solve a mystery. People reading OBD2 data (via something like a SG) have a simple way to know if they've crossed over from closed-loop mode to open loop. Because OBD2 simply reports this.

Could you suggest what methodology I could use to detect open-loop on my car ('95 VX, OBD1)? I've been having a hard time finding an answer to that, and I'm hoping you might know.

[Duffman]

Originally Posted by monroe74

Could you suggest what methodology I could use to detect open-loop on my car ('95 VX, OBD1)? I've been having a hard time finding an answer to that, and I'm hoping you might know.

Your car may not use open loop outside of startup and sensor failure.

[monroe74]

"Your car may not use open loop outside of startup and sensor failure."

Thanks for the quick response. I was sort of suspecting that.

This brings me back to my attachment to WOT. It seems that many people call for 70-80%, rather than WOT, and they point out that the risk of going too far is that open-loop is induced. By maybe this wideband-sensor motor is immune to that problem.

[Duffman]

Some Ford 5.4L stats indicating RPM creep:
1999-2004 - 2V V8 260HP @4500 350lb. ft. @2500
2005-present - 3V V8 300HP @5000 365lb. ft. @3750
Source: http://www.ford-trucks.com/specs/index.html

[Duffman]

Originally Posted by monroe74

This brings me back to my attachment to WOT. It seems that many people call for 70-80%, rather than WOT, and they point out that the risk of going too far is that open-loop is induced. By maybe this wideband-sensor motor is immune to that problem.

Its not really a problem, going rich gives the manufacturers a few extra HP out of thier engines, yours will be the same, your is just better at it because it has a wide band O2.

[monroe74]

"your is just better at it because it has a wide band O2"

OK, that's what I figured, thanks for explaining.

"RPM creep"

Interesting trend. There's surely some rationale behind it, but I have no idea what that would be.

[Duffman]

HP = Torque (in lb-ft) x RPM/5252
Two ways to build HP, more torque or more RPM with the same TQ.

[DifferentPointofView]

Edmunds thinks your torque peaks at 4k, not 3k. And the redline is 4750.

Edmunds is a bunch of retards. They said my moms 02 stratus didn't come in a 4 door SE model. (back when she still had it, They might have fixed that now)

DUDE!!! the 2008 Grand Cherokee uses a 3.7L V6!!!! that engine is nothing like the legendary AMC 242cu in. 4.0L I6!!! Believe me, I know Jeeps, the peak torque is between 3000-3200 RPM, and peak HP is at 4400rpm. The rod lengths for it are 6.125 in (155.6 mm)

Here's actual dyno testing starting at 3300RPM, These tests are not at the crank Which is why they aren't as high as they should be. As you can see, torque severely drops off after about 3800RPM. how it could peak at 4k I don't know. It's even higher near 3k.