Livernois Mycalibrator Tune Claims 50HP Gains (on E85) for V6 JL Wrangler

[JeepinPete]

I'll try to get a video this weekend. But to try to put it in words. At one point on my commute, I have to turn onto a highway from a side street. Half the time I need to use max acceleration to keep from getting run over. So first gear to redline, shift to second, the engine does not lower in rpm. Let out the clutch and the Jeep lurches from pulling the engine down in rpm.

Another situation I ran into was in 1st gear low range. Ran the engine up to 4500 rpm or so and held it there for a few seconds. When I let off the throttle, the engine kept at that rpm for a few seconds more.

Pete

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[moto_mike]

For what it's worth... I've found that after disconnecting the battery to reset the pcm, the rev hang just about disappears. Then it creeps back and gets progressively worse the more the truck is driven.

 

[Jeepjunkie]

For what it's worth... I've found that after disconnecting the battery to reset the pcm, the rev hang just about disappears. Then it creeps back and gets progressively worse the more the truck is driven.

ditto, I do this and it lasts a thousand miles or so. Maybe more.

 

[Livernois Motorsports]

ok, so we have made it much, much more responsive. There are still 1-2 scenarios that it still crops up, but it's been pretty solid progress, it'll actually slightly chirp the tires when letting out of the throttle abruptly at high rpm.

 

[Toycrusher]

ok, so we have made it much, much more responsive. There are still 1-2 scenarios that it still crops up, but it's been pretty solid progress, it'll actually slightly chirp the tires when letting out of the throttle abruptly at high rpm.

Oh great. Now your getting me excited!

 

[Livernois Motorsports]

another follow up, while we haven't made more progress, I will say, after driving it in the rain (not on purpose, but I am glad it happened) this will be by request only as if you are coasting down, it WILL lock up the rear wheels on a downshift. So you've got to drive with care.

 

[Toycrusher]

another follow up, while we haven't made more progress, I will say, after driving it in the rain (not on purpose, but I am glad it happened) this will be by request only as if you are coasting down, it WILL lock up the rear wheels on a downshift. So you've got to drive with care.

Wow, thank you for sharing. At what rpm range (and transmission gears) is the compression braking strong enough to lock the wheels? Or all rpm? Perhaps there is a middle-ground that greatly reduces the hang without eliminating it completely?

You guys know what your doing. I'm just excited on the progress being made!

 

[Kreepin1]

Wow, thank you for sharing. At what rpm range (and transmission gears) is the compression braking strong enough to lock the wheels? Or all rpm? Perhaps there is a middle-ground that greatly reduces the hang without eliminating it completely?

You guys know what your doing. I'm just excited on the progress being made!

Andy mentioned it will chirp the tires sometimes in the dry, my guess is you will need to feather the accelerator in the wet like when you rev-match.

BTW, it's my Jeep he's doing 360's in the rain with. I'm sure it was exciting - especially since you can hardly see out the half doors in the rain! LOL!

On a serious note, now we know why the factory made the rev hang so obnoxious. luckily I won't be driving this Jeep in the snow and ice...

 

[Livernois Motorsports]

Wow, thank you for sharing. At what rpm range (and transmission gears) is the compression braking strong enough to lock the wheels? Or all rpm? Perhaps there is a middle-ground that greatly reduces the hang without eliminating it completely?

You guys know what your doing. I'm just excited on the progress being made!

I would say 4k+ is strongest, but sometimes 3-4k does as well. it's a quick chirp and then good, so it's nothing major when dry, but definitely a pucker moment when not.

Andy mentioned it will chirp the tires sometimes in the dry, my guess is you will need to feather the accelerator in the wet like when you rev-match.

BTW, it's my Jeep he's doing 360's in the rain with. I'm sure it was exciting - especially since you can hardly see out the half doors in the rain! LOL!

On a serious note, now we know why the factory made the rev hang so obnoxious. luckily I won't be driving this Jeep in the snow and ice...

luckily not a full 360, but probably 40-50* of rotation on an exit ramp. the wording of the phone call definitely started going through my head though lol

 

[Kreepin1]

luckily not a full 360, but probably 40-50* of rotation on an exit ramp. the wording of the phone call definitely started going through my head though lol

To be fair, I borrowed some old wheels and tires off a friend's JK which would be more dyno friendly than my 35" Nitto Trail Grapplers. I'm sure the hard rubber and lack of tread didn't help matters any. Personally, I don't expect to chirp the 35's in dry weather but I'll certainly take it easy in the rain.

 

[Five Seasons]

To clarify this chirping is ocurring when you are mismatching a downshift and releasing the clutch ? Or it happens when you are reving out the engine and come hard of the throttle with no gear shifts ? Or are you saying that you are losing traction during upshifts due to the better response ?

 

[Livernois Motorsports]

To clarify this chirping is ocurring when you are mismatching a downshift and releasing the clutch ? Or it happens when you are reving out the engine and come hard of the throttle with no gear shifts ? Or are you saying that you are losing traction during upshifts due to the better response ?

moderate aggressive acceleration event, full lift on pedal, starts decel so aggressively it chirped the tires on decel. no gear change, no clutch or throttle input.

 

[zakaron]

moderate aggressive acceleration event, full lift on pedal, starts decel so aggressively it chirped the tires on decel. no gear change, no clutch or throttle input.

Wow, I was not expecting a condition like that. Must be a super light flywheel to drop revs so quickly. Anyway, glad to hear you are getting that pesky rev hang sorted out.

 

[Toycrusher]

@Livernois Motorsports
So how much progress have you made on the rev hang during shifts? I.e. - accelerate in 1st gear to above 4K rpm and depress clutch to shift to 2nd…..revs hang at 4K + for a couple seconds before dropping on their own or releasing the clutch in the next gear.
This is what I am interested in getting fixed.

Based on the past few posts, looks like it's eliminated completely!

 

[Kreepin1]

@Livernois Motorsports
So how much progress have you made on the rev hang during shifts? I.e. - accelerate in 1st gear to above 4K rpm and depress clutch to shift to 2nd…..revs hang at 4K + for a couple seconds before dropping on their own or releasing the clutch in the next gear.
This is what I am interested in getting fixed.

I can verify that this is fixed, at least for the 2021's. Revs begin to drop as soon as you shift. Rev hang comes back under a few cases; for example if you are on the throttle, then off the throttle still in gear, then on the throttle, then shift. I also noticed a bit of erratic idle control before the engine warms up but otherwise drivability is much improved. This is how the Jeep should have been from the factory.

I haven't had a chance to run any trails yet to see how engine braking is, just blasting around the Silver Lake dunes and maybe 90 street miles. I'll post up after I get more seat time.

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