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What Do You Consider To Be A Respectable Crawl Ratio?

nvrenuf

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Ok, <font color="orange">TARussell</font> and I met <font color="orange">Russ</font> this yesterday and got to ride in his K5 (VERY NICE!). Russ' truck has a 117:1 set up, it feels very strong and, while we didn't do anything crazy, it easily crawled on/over everything in front of it.

Now my point, I plan on running a TH400 and even with a Doubler and 5.86 gears my truck will only be around 57:1 - is this worth the cost?

I'm not trying to achieve a specific number nor am I concerned with going for the ultimate number, I'm simply curious as to what do you guys consider to be a decent, respectable starting point? You know, is 40:1 a good or a joke? 60:1, etc.
 
It depends on if it's a stick or slush box. Sticks work best in the big rocks when the ratio exceeds 100:1, but it's possible to get too crazy and end up with a rig that barely moves in low range. /forums/images/graemlins/wink.gif

With a Turbo 400, 203/205 doubler, and 4.10 gears, I figured that I would only end up with a little over 39:1. /forums/images/graemlins/eek.gif But that beats the crap out of the 400/205/4.10's ratio of a measly 19.9:1. /forums/images/graemlins/yikes.gif

You can get away with a much lower number with a slush box, since the torque converter lets you vary the amount of hook up. /forums/images/graemlins/cool.gif
 
I am at 320:01 with the auto and love it. I would like to be lower. I play on large ricks, large ledges and whatever else looks nutty!!
 
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I am at 320:01 with the auto and love it. I would like to be lower.

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/forums/images/graemlins/yikes.gif /forums/images/graemlins/yikes.gif That is so wrong! /forums/images/graemlins/histerical.gif /forums/images/graemlins/histerical.gif
 
Transmission ratio x t-case ratio x diff ratio = crawl ratio

/forums/images/graemlins/thumb.gif
 
what's the avrage ratio for a sm 465 tranny /forums/images/graemlins/deal.gifi would like to figure my crawl ratio but i don't know this number
this tranny is mounted with a doubler (4-1 i think) and 4.10 gears anyone got the answer? /forums/images/graemlins/peace.gif /forums/images/graemlins/peace.gif
 
The SM465 first gear ratio is 6.55.

Are you saying your Doubler is 4:1 or your Doubler w/ t-case is 4:1?
 
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im happy at 50 to 1

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I was more than happy in Moab with 58.5:1...

Rene
 
I am running about 50 to 1 and wish I was lower. I am either going to go to a doubler or Dual tranny's. I am collecting parts for both as I have not decided yet.
 
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The SM465 first gear ratio is 6.55.

Are you saying your Doubler is 4:1 or your Doubler w/ t-case is 4:1?

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205 t case with 203 range box i think it's 4:1
if thats the case i will have 107.42:1 /forums/images/graemlins/yikes.gif
can this be right that's preaty sweet
 
[ QUOTE ]

205 t case with 203 range box i think it's 4:1
if thats the case i will have 107.42:1 /forums/images/graemlins/yikes.gif
can this be right that's preaty sweet

[/ QUOTE ]

Yep, that's right. You see that's my dilema, with a TH400 my c/r is 57:1 but with a 4spd it jumps to 150:1! /forums/images/graemlins/yikes.gif I love the auto but with the 4spd wow what a difference. /forums/images/graemlins/doah.gif /forums/images/graemlins/thinking.gif
 
Go with the stick. You know you want to. /forums/images/graemlins/grin.gif

Russ
 
are you factoring in torque converter slippage? Basically double your crawl ratio for that.
 
Stop fighting it John ! You already own the McLoed Dual Disc clutch for a BBC and I have a spare 465/203 adapter that is all yours if you will step up and get a real transmission ....... /forums/images/graemlins/whistling.gif
It is VERY obvious that you enjoyed yourself while driving Russ's Blazer on Sunday - You need the granny gear !!!!!! but I am not trying to influence you in any way shape or form ..... /forums/images/graemlins/dunno.gif /forums/images/graemlins/thumb.gif
Just incase you forgot---- the pedal to the left of the brake is the clutch ......... /forums/images/graemlins/thumb.gif
Tom
 
I think anything more than 50:1 or so is respectable.

I think the statement that a torque converter doubles your effective crawl ratio is horse hockey. It helps but it sure as hell doesn't double the ratio.

A clutch can be slipped too...

I have wanted a lower ratio a few times but I find my 465/205 with 4.10s to be pretty good. When I get my 5.13s I think it will be perfect.
 
I am running 36.42:1 in my truck right now. It crawls anything I want with VERY little throttle input. I am also only running 35" tires. With the FI and the low stall converter in the tranny (1000-1200rpm) it has PLENTY of torque and to much throttle response. With my setup now if I can't climb it at 1000 RPM I can't climb it. I just spin tires after 1000RPM. Before my next trail run I am going to adjust my TPS setting down to hopefully get less throttle response.

If I were to step up to 38's though my crawl would be alot worse then it is. It is all dependent on your combo.

36.5:1 with a low stall, FI w/low end torque, and 35's is great. Bigger tires require more crawl. That is the nature of the beast.

Manuals need more crawl then auto's do because of the torque converter effect.

Necessary crawl ratio is also dependent on the type of wheeling you do. Here in AZ it is technical rock crawling. Deeper is better here.

Harley
 
I've only crawled with 2 vehicles, my old K5 and my Burb. My burb has a crawl ratio of about 60:1, my K5 had one of about 48:1. I definetally wanted a lower ratio. But at the sametime, I only had a rear locker on the K5(welded truly), and crap tires on both of them. First time I hit the trail in the new K5 I will have a ratio of about 73:1. Until I get the 5.13 installed then its 91.4:1 /forums/images/graemlins/grin.gif
 
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