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bwillrich

bwillrich

Spotter Required
Joined
Aug 18, 2022
Messages
29
Location
Iowa
After a long while of stalling I finally started on my Rock Lizard project. It’s my first time with a project of this magnitude but as I stumble along progress is being made!
Drivetrain is a GM 3900/ 700r4/nwf eco205. 79 hp60/14 bolt rear. Hope to have the engine settled in and mounts built over the weekend. I know it’s going to be a super tight fit.

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Can't wait to see what all you come up with!! I can see you modified the rear of the chassis. Is that to make it a small 4 seater? Looks great!! keep up the good work.
 
Blase said:
Can't wait to see what all you come up with!! I can see you modified the rear of the chassis. Is that to make it a small 4 seater? Looks great!! keep up the good work.
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I bought it from a guy that did that. He said he liked the wagon look. I agreed and that was a big part of buying it for me. He also had some custom suspension set up by BFR made specifically for it also. Tim does good work so I’m anxious to see how it works. Not enough room for an extra seat but it’ll be nice for a little more storage.
 
vogelj said:
Looks like a great build! Im in for the 3.9 700R4 tech. Did you do anything to refresh the engine?
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I flipped the intake around and new gaskets for that, and did the oil pickup mod but nothing else. It was a good runner before so I figured it’d be ok.
 
man when I was looking at chassis this was a serious consideration saw one at KOH 2022 and fell in love with it
looking forward to seeing it come together!
 
Moving forward… Tcase mount arrived. Fit good with very minimal effort. Got the rear links in place and heavily tacked in. Moved on to the front and realized the front pinion wants to be in the same place and my relocated power steering pump. So I guess if someone needs an Eversen Fab aluminum bracket, hit me up😁. I had plans of flipping the intake around but I guess that’s not going to fly. Planning to spin the intake back around and put the pump in the stock location , just need to find the correct coolant crossover.

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Very interested in how you end up liking the np205/EcoBox combo. How often you use double low vs just 2.7 of the EcoBox or 1.9 of the np205. How deep are you going with your ring & pinion's?
 
mustcamp said:
Very interested in how you end up liking the np205/EcoBox combo. How often you use double low vs just 2.7 of the EcoBox or 1.9 of the np205. How deep are you going with your ring & pinion's?
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I’ve got 5.38’s in the axles. I have a buddy with the same setup with a Jeep 4.0 in his buggy. He says for crawling technical stuff the low-low is great but it’s too slow for some hill climbs. I guess I’ll find out, but I think it’ll be a good mix. I wish there was more of a difference between the 2.72 and the 1.96. I had this stuff when I had my xj and never got around to putting it in. Otherwise I think an atlas or something smaller would have been a better choice.
 
bwillrich said:
I’ve got 5.38’s in the axles. I have a buddy with the same setup with a Jeep 4.0 in his buggy. He says for crawling technical stuff the low-low is great but it’s too slow for some hill climbs. I guess I’ll find out, but I think it’ll be a good mix. I wish there was more of a difference between the 2.72 and the 1.96. I had this stuff when I had my xj and never got around to putting it in. Otherwise I think an atlas or something smaller would have been a better choice.
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Thanks... It seems like most who have this set up that I can find writeup are not disappointed other than the size. I figured between the two ratios and being able to double up in addition to using second gear start you have a lot of options depending on the obstacle. strength, front dig capable and ratio options. It's the direction I was planning to go. for me us coming from dual Toyota cases and manual trans I just feel more comfortable with the options and willing to sacrifice the weight and size.
 
mustcamp said:
Thanks... It seems like most who have this set up that I can find writeup are not disappointed other than the size. I figured between the two ratios and being able to double up in addition to using second gear start you have a lot of options depending on the obstacle. strength, front dig capable and ratio options. It's the direction I was planning to go. for me us coming from dual Toyota cases and manual trans I just feel more comfortable with the options and willing to sacrifice the weight and size.
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Create a spreadsheet for your ratios, covering all your t-case options and trans options. I've done that for my next build, very useful info. Notice that for my current 700r setup, the Third L and First H overlap. The C4 ratios are specifically being chosen to NOT overlap.

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woody said:
Create a spreadsheet for your ratios, covering all your t-case options and trans options. I've done that for my next build, very useful info. Notice that for my current 700r setup, the Third L and First H overlap. The C4 ratios are specifically being chosen to NOT overlap.

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Whats the theory about not overlapping in a higher ratio? I know im regularly not in Third/Fourth L when doing anything technical. And im only in high on the park roads. I figured 1st/2nd low range are the most important crawl ratios to look at. Just curious.
 
woody said:
Create a spreadsheet for your ratios, covering all your t-case options and trans options. I've done that for my next build, very useful info. Notice that for my current 700r setup, the Third L and First H overlap. The C4 ratios are specifically being chosen to NOT overlap.

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I see you are going much lower with your 1st Low. on your new set up. Do you currently wish for a bit lower crawl in First-Low? The C4 1st, 2nd, 3rd splits look really nice. Will you be able to stop it or just pop neutral?
 
mustcamp said:
I see you are going much lower with your 1st Low. on your new set up. Do you currently wish for a bit lower crawl in First-Low? The C4 1st, 2nd, 3rd splits look really nice. Will you be able to stop it or just pop neutral?
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I mostly stop in 2nd now, 75:1 can push thru the brakes :)

Yes, I'd like to be lower on occasion, but 90% of the time 75:1 is perfect, and use 2nd for throttle bumps. The new ratios would bump in 3rd, normal wheel in 2nd, crawl in 1st. There are also lower 1/2 ratios available for the C4, toying with that option too.
DirtSquirrel said:
Whats the theory about not overlapping in a higher ratio? I know im regularly not in Third/Fourth L when doing anything technical. And im only in high on the park roads. I figured 1st/2nd low range are the most important crawl ratios to look at. Just curious.
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Takes a split second to stop and hit high, not overlapping offers the most options for gearing as needed.
 
Had to take some time to keep the rest of our families fleet running but finally back after this! Got the engine mount and winch sorted out. Also have a preliminary design for the rear cargo area. I need to get the rear ORI’s mounted and make sure they don’t hit. As the suspension cycles. Keep moving forward!!

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You have made good progress, but those bars at the B pillar look like you are just asking to knock yourself out. I would look at those again.
 
vogelj said:
You have made good progress, but those bars at the B pillar look like you are just asking to knock yourself out. I would look at those again.
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They look close in the pictures but there’s actually a fair amount of room.
 
how are you mounting the seats? I struggled with this involved tacking and cutting off mounts a few times a third arm would have helped.

ended up doing a pseudo copy of woodys method
 
Dave22 said:
how are you mounting the seats? I struggled with this involved tacking and cutting off mounts a few times a third arm would have helped.

ended up doing a pseudo copy of woodys method
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I haven’t gotten there yet. I really like Woody’s method but I’ll have to see what I can make work.
 
After a family vacation and life stuff I finally got some time to get back to this. After 4 different front shock mounting ideas this is the one I hated the least. It’ll have the tubes capped and a couple gussets. The winch fits snug also. Angle of the shock is good though the travel. Hopefully be able to move on to another part of the puzzle now!

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Back at it again. Radiator mounted with a TMR mount. Fuel cell in. Hydroboost and carrier bearing shaft in place. Seat mounts done. I’m not a huge fan of the seat mounts but they’ll work fine. Only one bolt is slightly difficult to access.

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