I've blown a few R&P's with the semi float rear driving hard with it. I suspect it's the "fuse" for the most part.
Building An 80 Series Rearend For Desert Racing On A Budget.
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I've blown a few R&P's with the semi float rear driving hard with it. I suspect it's the "fuse" for the most part.
Blowing a 10.5 ring and pinion should be alot harder to blow than a 9.5"......its a huge chunk beefier
For desert racing i still think the axle housign is the weak link---but he has beefed them up with a truss.......so then the next weak link id say is thst necked down shaft.
In which case - watching your rear wheel launch past you over a dune in baja would be.....exciting......to say the least
For desert racing i still think the axle housign is the weak link---but he has beefed them up with a truss.......so then the next weak link id say is thst necked down shaft.
In which case - watching your rear wheel launch past you over a dune in baja would be.....exciting......to say the least
RustyNailJustin
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Blowing a 10.5 ring and pinion should be alot harder to blow than a 9.5"......its a huge chunk beefier
For desert racing i still think the axle housign is the weak link---but he has beefed them up with a truss.......so then the next weak link id say is thst necked down shaft.
In which case - watching your rear wheel launch past you over a dune in baja would be.....exciting......to say the least
I have had a tire and wheel pass me 2 times. Once with the semi float 80 that snapped in a rock to short course transition during the prelem race at 2017 Nationals.
The other time was doing 80 in the desert in the 4431 car in 2014. That was scary. The tube snapped taking brakes, wheel, tire and about 6” of housing with it. I will try to dig up a picture of the that.
Blowing a 10.5 ring and pinion should be alot harder to blow than a 9.5"......its a huge chunk beefier
For desert racing i still think the axle housign is the weak link---but he has beefed them up with a truss.......so then the next weak link id say is thst necked down shaft.
In which case - watching your rear wheel launch past you over a dune in baja would be.....exciting......to say the least
I suppose so, Also not a very good "apples to apples" comparison. 6BT 80 vs lighter toyota truck at higher speed. I guess the damage I have seen is more due to torque, and his more due to impacts at speed.
RustyNailJustin
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Hand built rear truss out of 3/16”
All cut by a cutoff wheel none of that fancy s***
Just gotta get the traction bar mounts on and she is ready for finish welding.
All cut by a cutoff wheel none of that fancy s***
Just gotta get the traction bar mounts on and she is ready for finish welding.
Nice truss. Are you going to truss it outward of the spring perches? Not sure how hard your going to be on it as far as jumping it.
RustyNailJustin
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Yes it has a piece of 1 3/4 .250 wall tube cut in half and laid on top like the V1.
We never had any issues bending rear axles even jumps and plowing stuff on course. So I hope it works out for V2 as well. This truss is much better and about the same weight
Might want to look into some wedge lock washers “Nord-Lock” for those 7/16” bolts, we’ve used these washers solve the issue of loosening bolts on the Dana 60 with great success. Cheap insurance for you on a race car.
McMaster-Carr
Nord-Lock Washers
Nicely done.
What size are you drilling the axle flange to for the larger fasteners?
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The shank of the bolt is 7/16”. The original taper from the cone washer only leaves about 60% of the flange thickness to be contacted by the bolt shank. Not horrible. The remaining taper does give a nice chamfer so the bolt flange sits flat with the axle flange face.
If I ever get Nitro shafts I will call them and see if they’ll send them un-drilled, or drilled to 7/16” straight. The shank contact is important
If I ever get Nitro shafts I will call them and see if they’ll send them un-drilled, or drilled to 7/16” straight. The shank contact is important
Never raced anything so may be a stupid question but why dual cases? Why all the gearing to go fast?
RustyNailJustin
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Ultra4 is the mixed martial arts of desert racing.
High speed desert into nasty rock canyons.
Youtube king of the hammers.
RustyNailJustin
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Getting them to straight drill would be great. Opening up the taper was not terrible but pretty pretty hard steel.
RustyNailJustin
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- #54
Got it jigged up to weld the handmade truss. It's now all finish welded and ready to be put in the car and assembled.
At this point I have less that 2500$ into it but lots of labor, maybe 50 hours, lame. But it should live for awhile.
At this point I have less that 2500$ into it but lots of labor, maybe 50 hours, lame. But it should live for awhile.
RustyNailJustin
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The lower shock tabs looked unfinished so I built these captures. Looks better and will protect the shock ends which in the past have been a consumable, changed out at ever rebuild or tuning session.
And of course happy New year gents.
And of course happy New year gents.
Looks awesome man. Did you check for straightness after welding? Curious more than anything, that's a lot of welding.
Kinda sucks how long quality fabrication takes, but the end result sure is pretty
Kinda sucks how long quality fabrication takes, but the end result sure is pretty
RustyNailJustin
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Looks awesome man. Did you check for straightness after welding? Curious more than anything, that's a lot of welding.
Kinda sucks how long quality fabrication takes, but the end result sure is pretty
I I am really glad I chained it down and pre-loaded the axle with the jacks. Even doing that there is about a sixteenth of Warp.
I'm really surprised it was able to move at all as much pressure was on the housing.
RustyNailJustin
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- #58
Rear is under the truck for dry fit to double check everything.
Everything lined up perfect and the fitment on all accounts I am very happy with.
Here are some more budget build parts. These
Drilled and slotted rotors, calipers and pads were under 300$ from R1 concepts. I will report back after they get beat on but the finish and fitment are really nice.
Everything lined up perfect and the fitment on all accounts I am very happy with.
Here are some more budget build parts. These
Drilled and slotted rotors, calipers and pads were under 300$ from R1 concepts. I will report back after they get beat on but the finish and fitment are really nice.
I think you better hurry, City Racer might catch you!
Looks awesome 
