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-   -   Hypertech rev limiter adjustment (http://www.jeepgarage.org/f6/hypertech-rev-limiter-adjustment-71976.html)

carvinbassplyr 02-21-2014 12:52 PM

Hypertech rev limiter adjustment
 
Just wondering if people have any guidelines to a safe range of adjustability? I have a flex fuel 4.7, CIA, 255/65/17 tires and cat-back. Does anyone know what the factory rev limiter is set at? What are folks setting theirs at?

carvinbassplyr 02-21-2014 10:53 PM

Does no one at least know where the factory limiter is set? I know that these motors make their peak power btwn 4800-5000 rpm's so by knowing the stock rev limit I can try to manipulate it in the right direction (up or down) to help keep the motor in the sweet spot through all the gears.

Strongjeff 02-21-2014 11:59 PM

Re: Hypertech rev limiter adjustment
 
I believe its 6k as it was on my 3.7 same engine yours just has 2 more cylinders

Strongjeff 02-22-2014 12:00 AM

Re: Hypertech rev limiter adjustment
 
I bumped it 6250

carvinbassplyr 02-22-2014 07:48 AM

Quote:

Originally Posted by Strongjeff (Post 980073)
I bumped it 6250

The 3.7 makes it's peak power higher up in the rpm range (5200) and smaller motors can usually handle higher rpm's better. With the 4.7 making peak power @ 4500 rpm's, I don't see the need to go much past 5000 since you're losing power at that point. That's why I need to know where the stock rev limit is so I can know how much to bump it up or down to help keep it in the sweet spot.

Strongjeff 02-22-2014 07:54 AM

Quote:

Originally Posted by carvinbassplyr (Post 980231)

The 3.7 makes it's peak power higher up in the rpm range (5200) and smaller motors can usually handle higher rpm's better. With the 4.7 making peak power @ 4500 rpm's, I don't see the need to go much past 5000 since you're losing power at that point. That's why I need to know where the stock rev limit is so I can know how much to bump it up or down to help keep it in the sweet spot.

Its 6k like the 3.7. Its the same

kennzz05 02-22-2014 09:11 AM

Re: Hypertech rev limiter adjustment
 
unless youre racing then why bother,doubt youll notice any difference

but to find out what its limited at, get it in third and hold it on the floor till its starts bouncing off the limiter
from a brief search looks like peak torque is at 3800 and redline is 5800 to 6000

carvinbassplyr 02-22-2014 02:01 PM

Quote:

Originally Posted by kennzz05 (Post 980260)
unless youre racing then why bother,doubt youll notice any difference

but to find out what its limited at, get it in third and hold it on the floor till its starts bouncing off the limiter
from a brief search looks like peak torque is at 3800 and redline is 5800 to 6000

What drew my attention toward the rev limiter (b4 even having a programmer) was how the motor was rev'ing when merging onto express ways. I noticed, on more than one occasion, that when I had to get up to speed fast the motor was rev'ing out farther than what even seemed safe before finally down-shifting. Having a rev limiter set @ 6k on a motor that makes full power @ 4.5k doesn't seem logical. You're putting more stress on parts without gaining anything. Maybe when I do the 2008+ intake mani swap I'll let the motor rev out a little farther since that manifold flows well beyond 6k, but until then I'm trying to milk the motor's stock sweet spot.

kennzz05 02-24-2014 03:30 AM

Re: Hypertech rev limiter adjustment
 
you could shift it manually, not a solution but a suggestion

Strongjeff 02-24-2014 03:51 AM

Re: Hypertech rev limiter adjustment
 
Quote:

Originally Posted by carvinbassplyr (Post 980340)
What drew my attention toward the rev limiter (b4 even having a programmer) was how the motor was rev'ing when merging onto express ways. I noticed, on more than one occasion, that when I had to get up to speed fast the motor was rev'ing out farther than what even seemed safe before finally down-shifting. Having a rev limiter set @ 6k on a motor that makes full power @ 4.5k doesn't seem logical. You're putting more stress on parts without gaining anything. Maybe when I do the 2008+ intake mani swap I'll let the motor rev out a little farther since that manifold flows well beyond 6k, but until then I'm trying to milk the motor's stock sweet spot.

then I would drop it down to about 5,7k that way when it shifts you land deeper in the power band. I shift at 6k cuz when it hits the net gear around 3800-4200 im in the sweat spot for torque and then it builds into the peak horsepower range. Granted I have the 3.7 and the 4.7 is not all that different, the power curves are similar when stock. now with all my mods it pulls from 3k all the way to 5800

carvinbassplyr 02-24-2014 09:07 AM

Quote:

Originally Posted by Strongjeff (Post 981209)

then I would drop it down to about 5,7k that way when it shifts you land deeper in the power band. I shift at 6k cuz when it hits the net gear around 3800-4200 im in the sweat spot for torque and then it builds into the peak horsepower range. Granted I have the 3.7 and the 4.7 is not all that different, the power curves are similar when stock. now with all my mods it pulls from 3k all the way to 5800

I set it @ 5500 for now. We'll see how that feels through the gears.


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