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-   -   Crawl Ratio?? (http://www.elcovaforums.com/forums/showthread.php?t=18464)

Michael1 07-15-2006 05:20 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by Wisha Haddan H3
It's best in class for 2006 models, but the 2006 JK Rubicon Ultd will beat it next year. The source I used for this graph supplied different numbers than the ones in this thread. I'll update them when I get a chance.


You forgot the Dodge Power Wagon with manual transmission at 78.3. That ought to be enough for any of you ladies.:D

Michael

f5fstop 07-15-2006 08:46 PM

Re: Crawl Ratio??
 
Actually, I found the 56:1 ration quite substantial and almost felt too low from my Jeep days.:D

After spending 4.5 hours cleaning red dust out of the interior, treating the leather, pressure washing the red tires back to black, washing the vehicle, all in 90+ humid heat, my personal crawl ratio is lower than any on that chart.

HummBebe 07-15-2006 10:40 PM

Re: Crawl Ratio??
 
poor f5....would you like me to get you a Lemonade???:D

Idaho-Hummer 07-15-2006 10:57 PM

Re: Crawl Ratio??
 
Nah, he just needs some cheese to go with that wine. :D

f5fstop 07-16-2006 01:55 AM

Re: Crawl Ratio??
 
Quote:

Originally Posted by HummBebe
poor f5....would you like me to get you a Lemonade???:D


Prefer Captain Morgan's Silver....:D

In the Kroger Parking Lot after the wash job:


Eye of the Whale Arch, Arches NP:


Monument Valley (darn kid in the way and taking photos):

rkcrawl 07-16-2006 02:10 AM

Re: Crawl Ratio??
 
There are advantages to both: Manual vs Auto.

I have run both in competive (UROC Rockcrawling competitions) environments.

The biggest advantage, IMO, is down hill engine braking. A super low crawl ratio in a manual transmissioned vehicle gives you excellent control of the vehicle (way more then an auto) as long at the tires have traction.

Auto's on the other hand are a ton easier to drive, you've got one less peddle to deal with and very granular control of the vehicle motion. And yes, the GENERAL consensus in the 4x world is a factor of 2 when considering the torque convertor in the crawl ratio, however its just that when CRAWLING at low rpms. Its not exact, nor scientific, but I can tell you from the seat of the pants, its noticable when crawling level or uphill grades. I drove my old rig with both, and the only change being going from a SM465 4 speed with a granny 1st gear to a Turbo 350 with a full manual valve body. The difference was VERY noticable. The TC is not a factor down hill. Thats the auto's biggest disadvantage (again, just my opinion) because you need to rely more on the vehicle brakes, rather then engine braking. I think the second biggest issue/concern is transimssion failure potential.

f5fstop 07-16-2006 02:19 AM

Re: Crawl Ratio??
 
Quote:

Originally Posted by rkcrawl
There are advantages to both: Manual vs Auto.

I have run both in competive (UROC Rockcrawling competitions) environments.

The biggest advantage, IMO, is down hill engine braking. A super low crawl ratio in a manual transmissioned vehicle gives you excellent control of the vehicle (way more then an auto) as long at the tires have traction.

Auto's on the other hand are a ton easier to drive, you've got one less peddle to deal with and very granular control of the vehicle motion. And yes, the GENERAL consensus in the 4x world is a factor of 2 when considering the torque convertor in the crawl ratio, however its just that when CRAWLING at low rpms. Its not exact, nor scientific, but I can tell you from the seat of the pants, its noticable when crawling level or uphill grades. I drove my old rig with both, and the only change being going from a SM465 4 speed with a granny 1st gear to a Turbo 350 with a full manual valve body. The difference was VERY noticable. The TC is not a factor down hill. Thats the auto's biggest disadvantage (again, just my opinion) because you need to rely more on the vehicle brakes, rather then engine braking. I think the second biggest issue/concern is transimssion failure potential.


Are you saying in an auto the transfer case is not a factor? I just finished some extremely steep mountain roads in Canyonlands (park and area), and in 4-low lock, the car hardly moves downhill, in fact, you have to gas it a few times. In 4-wheel hi lock, it crawls a lot slower than when in 4-wheel non-lock. This was in first or second gear, not in drive.
I have also driven a Jeep manual down the same roads, and with the manual, I had to use the brakes (first or second gear). Granted the H3 has a 4:1 while the Jeep did not, but if I'm reading you correctly, you are saying the t/case has no affect on downhill? That I will dispute, since I have tried all the ranges and there is a noticeable difference.

PARAGON 07-16-2006 02:29 AM

Re: Crawl Ratio??
 
Quote:

Originally Posted by f5fstop
Are you saying in an auto the transfer case is not a factor? I just finished some extremely steep mountain roads in Canyonlands (park and area), and in 4-low lock, the car hardly moves downhill, in fact, you have to gas it a few times. In 4-wheel hi lock, it crawls a lot slower than when in 4-wheel non-lock. This was in first or second gear, not in drive.
I have also driven a Jeep manual down the same roads, and with the manual, I had to use the brakes (first or second gear). Granted the H3 has a 4:1 while the Jeep did not, but if I'm reading you correctly, you are saying the t/case has no affect on downhill? That I will dispute, since I have tried all the ranges and there is a noticeable difference.

No, I don't think that's what he was saying.

A lot of times an auto will "free wheel" some or something that seems to give less engine braking than a standard, transfer case remaining the same. I also keep my shifter in first or second depending upon what I am doing and most times first will allow the truck (H2) to ease down but there are steeper situations where braking is required.

The biggest difference between auto and standard is on an actual obstacle. When on most obstacles, rarely can you just crawl up it with out some stoppage and/or re-alignment, etc. This is a big reason why you see so many trucks with their foot to the floor bouncing and banging around.

With an auto, you can easily stop ON the obstacle, hold your brake, get your RPMs up to a higher torque range and ease off the brake to continue. Huge advantage over a standard transmission where you would have to heel/toe drive to accomplish the same.

f5fstop 07-16-2006 01:14 PM

Re: Crawl Ratio??
 
I agree, if you keep an auto in Drive, it will feel like it is freewheeling. I guess, I learned to run an auto similar to a manual, by using the shifter.
Oh well, if I read it wrong and rkcrawl meant the Torque Converter (TC), then I apologize and will lay off the Morgan's on Saturday night (no I won't:D ).

HummBebe 07-16-2006 04:43 PM

Re: Crawl Ratio??
 
The opinions on Auto Vs Manual, are like the opinions on IFS vs Straight axle.

If one more person starts talking to me about a straight axle swap, I'm gonna have t-shirts and stickers that say:

NO SAS for this girl:D

BACK OFF MY IFS:D

STRAIGHT AXLE IS FOR SISSIES:D

GOT STRAIGHT AXLE??? SUCKS TO BE YOU:D

IFS RULES, STRAIGHT AXLES DROOL:D

Not that I actually believe that, because I have some friends with straight axles, (yes, I am not prejudice). I understand the benefits, and the drawbacks. But I've had 2 shops figure that an SAS would run $7,500-$10,000, including top of the line Dana 60, steering fabrication, lift and driveline upgrades.

WHY??? I don't want a rock buggy, yet.

rkcrawl 07-16-2006 06:25 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by PARAGON

With an auto, you can easily stop ON the obstacle, hold your brake, get your RPMs up to a higher torque range and ease off the brake to continue. Huge advantage over a standard transmission where you would have to heel/toe drive to accomplish the same.


Well said.

rkcrawl 07-16-2006 06:28 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by f5fstop
I agree, if you keep an auto in Drive, it will feel like it is freewheeling. I guess, I learned to run an auto similar to a manual, by using the shifter.
Oh well, if I read it wrong and rkcrawl meant the Torque Converter (TC), then I apologize and will lay off the Morgan's on Saturday night (no I won't:D ).


Yes, I was referring to the torque convertor. Hope you enjoyed the Morgan's :D

rkcrawl 07-16-2006 06:30 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by HummBebe

Not that I actually believe that, because I have some friends with straight axles, (yes, I am not prejudice). I understand the benefits, and the drawbacks. But I've had 2 shops figure that an SAS would run $7,500-$10,000, including top of the line Dana 60, steering fabrication, lift and driveline upgrades.

WHY??? I don't want a rock buggy, yet.


But you'd have one kick ass H3. Someone's got to be the first to SAS an H3 :D

evldave 07-16-2006 07:18 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by PARAGON
With an auto, you can easily stop ON the obstacle, hold your brake, get your RPMs up to a higher torque range and ease off the brake to continue. Huge advantage over a standard transmission where you would have to heel/toe drive to accomplish the same.


Handle throttle does the same thing - just set the throttle, keep right foot on the brake, and then feather the clutch. Same as an auto, plus you get the advantage on downhills of full lockup in 1st gear.

...unless your foot slips off the clutch, in which case then you are totally f'd because your throttle is high and you are dumping the clutch, making your jeep hop over the rock you are on, smashing the right front fender on the next rock, ruining your day and costing thousands of dollars. So I hear:rolleyes:

I was a manual guy, still am sorta, but really like an auto for the ease of use.

rkcrawl 07-16-2006 08:40 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by evldave

I was a manual guy, still am sorta, but really like an auto for the ease of use.


That was me too, until I started competing... Auto's rule in rock crawling competition and it made me a convert.

HummBebe 07-16-2006 10:45 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by evldave
Handle throttle does the same thing - just set the throttle, keep right foot on the brake, and then feather the clutch. Same as an auto, plus you get the advantage on downhills of full lockup in 1st gear.



So now, for those with manual, can you install a hand throttle? Sounds like the way to go:D

f5fstop 07-16-2006 11:04 PM

Re: Crawl Ratio??
 
Anyone make a hand throttle for the H3? Haven't seen one for the electronic throttle (accelerate-by-wire) system on the H3.

PARAGON 07-16-2006 11:09 PM

Re: Crawl Ratio??
 
Quote:

Originally Posted by f5fstop
Anyone make a hand throttle for the H3? Haven't seen one for the electronic throttle (accelerate-by-wire) system on the H3.

Sure you have, it's called a walking cane.;) :eek:

PARAGON 07-16-2006 11:10 PM

Re: Crawl Ratio??
 
that or you could just wire in a potentiometer :D :D :D

HummBebe 07-16-2006 11:10 PM

Re: Crawl Ratio??
 
That was mean Para;)


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