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need serious gudiance here, what to do for new Jimmy, i want a crawler

BranndonC

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ok this post will be long, but if you know how to bulild a good crawler, please read and help me if you can.

The current situation:
1989 K5, dana 60, 14ff 5.13 locked, 700r4, np241, stock 350TBI with near 200,000 miles on it

it crawls "ok" but i'm not that satisfied, i probably give it a like 6 or 7/ out of 10 from what i want,

What i have to work with:
1973 GMC Jimmy, axles from 89, 500 caddy motor

What i'd like to accomplish:
i have gone through about 4 NP241 transfer cases some how with this setup. therefor i'd like to get away from them if possible, BUT i love low gears. i also need to keep it able to do 65 on the freeway as its my only vehicle for a little while.

what i'm thinking
new tranny - from bowtie or monster the beefed up 700r4
new t-case of some sort, maybe doubler or something, along with this i'd need new shafts

so basically i'm asking how i'd go about getting the lowest gearing possible/best crawling abilitys for a budget of say 3500-4000
i'll also be rebuilding the 500, since i have never touched a motor before, i dont know how to make it make more power than stock. ALL HELP IS GOOD HELP, dont think "well its common since that this or that will make power"
 
since you said on a budget... Go to pick and pull on a half off weekend, and find a truck with a 465/205 or a th350/205 and a $125 B&M rebuild kit, and you'll have a good tranny/tcase for a couple hundred bucks.
 
I thought you were a mud kind of guy?

/forums/images/graemlins/histerical.gif
 
With your budget I would look at a stock rebuild on the Caddy 500 with an aftermarket intake and QJet. Keep it simple and it will be reliable.

To make it a good crawler a doubler would be a good way to get that 10 out of 10 you want.

You already have the lift, axles and tires. /forums/images/graemlins/thumb.gif What size tires do you have, 42's?

Are you going to put the stock suspension and axles out of the '73 into the '89 and resell it to help out your budget then build up the '73?
 
I agree with a stock rebuild on the 500 with a performance intake and carb.
KISS="Keep It Simple Stupid"

A 205 is a must as it's apparent 241's don't like you /forums/images/graemlins/grin.gif

If you want an automatic trans get a Th400/NP205 combo.A little harder to find than the 350/205 but down your way I'm sure it's possible.
Otherwise do as Ryan said and get a 465/205 combo=bullit proof...or should I say "Branndon proof" /forums/images/graemlins/rotfl.gif

Your gonna love that full convertable 73. /forums/images/graemlins/thumb.gif
 
To be totally honest with you a 500 Caddy is going to be to much motor to crawl with. You do have alot of low end torque, but there is to much power to be had right off idle. It will make life on the drivetrain very hard and life as a driver kinda hard too.

I would rebuild the 350 and keep the TBI. FI is better then a Qjet at angle anyway. Better mileage too.

I would swap to a doubler or atlas behind a built 700R4 or if you can stand no OD then TH400. I wouldn't go with a 350. It is the same strength as a 700R4 and doesn't have OD. 700R4 will cost more but will save you more at the pump and make cruising at highway speed easier. 700R4 also has the 3.06 first gear. When you get your tranny rebuilt make sure it is built with a LOW stall. I am at 1200. Two of the other AZ crawlers I know are lower. AZK5 has around 1000 stall I believe and TheRobZilla has something stupid low like 600-800. He has problems stopping sometimes because once the converter is stalls it acts like a manual He runs a TH400 & doubler with TPI and it crawls like a demon. FWP has a TH350 & doubler and TBI and it crawls very well too.

The reason I say less motor is because of my experience with my TPI350 and Poorman's doubler (700R4 & NP208). With 4.56 gears and 35" tires I have almost to much throttle response and too much low torque. If I can't crawl over it at idle then I have to get into the gas a little. When this happens my TPI starts kicking out alot of torque and the torque converter starts to stall. I get so much torque with so little throttle input it I pop over things very quickly and you have to jump on the brakes. I have started learning to ride the brakes a little as I apply the throttle so I can control it better.

A good friend of mine knew a guy that built a K5 for heavy crawling awhile back. He built the drivetrain up D60/14bff, etc and had a mild-moderate 454 in it. After one season he pulled the 454 and dropped a 292 straight six. He said the 454 was hell to crawl with because of the torque and HP available at low end. The 292 had the torque he need to crawl well but lacked the HP's. It was easier on the drivertrain and also made the truck more crawlable.

Harley
 
thanks for the replys guys, i'm still researching everything, but like i said i do freeway speeds so i need the over drive, isnt the 465 stick? i'll re read all your replys later, i didnt have time to just now, thanks and keep them comming
 
[ QUOTE ]
www.500cid.com /forums/images/graemlins/waytogo.gifcheck out my rig, very similar

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lookin for the pics, its loading very very slowly

anyway since this is a TQ monster, i was thinking i really dont want a stick, so swap in a beefed 7004r, and a 205 if possible, and leave the gears alone and i'd be happy with it, i dont know why i'm so against stick, it just seems like its just one more thing to worry about on the trail /forums/images/graemlins/ignore.gif /forums/images/graemlins/1zhelp.gif
 
The 500 Caddy and the 700 tranny have different bellhousing bolt patterns, how do you get past that? I don't think there is a useable O/D tranny with the right bolt pattern. /forums/images/graemlins/thinking.gif
 
There is nowhere to put a pilot bearing/bushing in a 500 caddy so I'd nix that idea.

TH 400 would be the only factory option AFIAK.
 
with a 400 and the 203 that comes with the 73, i'd have
"First gear: 2.48 x T-case low: 2.01 x Differential: 5.13 = Final Drive: 25.57"
that just sucks, so what i'm thinking is either a doubler which would give me
"Underdrive: 2.01 x First gear: 2.48 x T-case low: 1.96 x Differential: 5.13 x Final Drive: 50.12"
which is just over the 43 that i'm at currently, now the last option is
465-205 which would give me
"First gear: 6.54 x T-case low: 1.96 x Differential: 5.13 = Final Drive: 65.76"
which would be great, but do you think the torque from caddy will be fine with the 50 crawl ratio

so basicaly heres my options right?
25 crawl ratio just via tranny/t-case
50 crawl ratio via doubler
65 ratio with 465-205......

opinions? /forums/images/graemlins/ears.gif
 
If you are building a crawler you really don't need 500 cubes. A good 350 with fuel injection is perfect. My suggestion would be, rebuild your 350, beef the 700 and put a doubler behind it. You get od, an auto, and a good crawl ratio. Sell that 500 caddy for more than ya bought it for. With the price of gas, I think this route makes the most sense. Good luck.
 
[ QUOTE ]
There is nowhere to put a pilot bearing/bushing in a 500 caddy so I'd nix that idea.

TH 400 would be the only factory option AFIAK.

[/ QUOTE ]

Not true, my neighbor ran a Clark 5-speed behind a Caddy 500 for years. He used the bellhousing from an Olds 442. Not sure what he did about the pilot.
 
One thing you should know though is that the crawl ratio of the manual is not the same as the crawl for the auto. Automatic transmissions have a torque converter that act like a torque multiplier. So 465/205 looks like it will have more crawl then a 400 & Doubler but it won't. A manual needs more crawl then an auto. Around 90-120 is the crawl you want out of a manual for full on rock crawling. So your looking at a doubler with either the TH400 or the 465. The 465 is a manual incase you didn't know.

Harley
 
[ QUOTE ]
One thing you should know though is that the crawl ratio of the manual is not the same as the crawl for the auto. Automatic transmissions have a torque converter that act like a torque multiplier. So 465/205 looks like it will have more crawl then a 400 & Doubler but it won't. A manual needs more crawl then an auto. Around 90-120 is the crawl you want out of a manual for full on rock crawling. So your looking at a doubler with either the TH400 or the 465. The 465 is a manual incase you didn't know.

Harley

[/ QUOTE ]

And if you run a low stall that effect is almost non existant. Funny how when talking crawl ratio guys will tell you all about the convertor and how it 'doubles' their crawl ratio, yet the first mod is a super low stall convertor to minimize that effect? If stall is so great and increases crawl ratio why not run a 3500 rpm convertor? /forums/images/graemlins/wink.gif

One thing about a 465 and crawling is not having to bump the gas a little to crawl over something. You just leave it in first gear with the clutch out and let it do its thing at idle. At 63:1 with 40's, I can idle along at under 1 mph without having to touch the clutch. I find 1 mph comfortable enough for most anything, and never found the need for much deeper while in Moab. Having a diesel does help though. It's a lot harder to stall than a gas engine...in fact in low range it'll probably smoke the clutch before stalling.

As for engine choice what could be simpler than keeping the stock 350 and the TBI? I don't know why anybody would purposely remove TBI in favor of a carb while building a 'rock crawler'...that's just going backwards.

A 500 caddy for crawling is also a bad plan IMO. Although the back of the crank can be drilled for a pilot (Tim..) and many people have run manuals behind them. It's heavier, and especially behind an automatic could just be way too much motor for the intended purpose. With a manual it might be more wheelable because it's got a little more off idle torque (kinda like a diesel) but I'd want FI regardless and that'll prolly blow the budget.

Rene
 
Branndon, if you reaaly want a big block, lets talk. I have that TBI 454 in Eeyore and I would rather a SB for the weight. Lets talk and maybe trade.

Or if you do go with the Caddy, let me know what you want for the complete 350 w/TBI, wiring and computer.
 
Here's my thinking, plus a few questions.

#1: Is it gonna be driven or on a trailer?
#2: How low do you want it?
#3: What is your ultimate tire size?

Any my thoughts. Ditch the 14 rear and go 70, then gear a [darn] outta your axles. Put the caddy motor in, build a 700, keep the 241 and see what you think. I figure a gearing in the 7's on the axles would change things around PLENTY!

You could also pick up a round pattern 205 and put a Klune in front of it.

These may not be the cheapest options, they will prb test that budget you setup, but it's just my thoughts. Me, I'm just gonna go rockwells and see how bad hydraulic steering REALLY is on the street /forums/images/graemlins/grin.gif
 

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