uh oh

[badassmav]

your pics and detailed explanation of why you did it, are very rare in this sport. Most teams keep everything quiet from build materials to their learning pains.

i understand wanting to keep everything quiet but dont forget about us little guys who learn from you and your trials and tribulations.

btw just from your pictures and explanation of how you moved the rear diff back i decided on chopping mine this summer and getting more whelbase.


Thanks BA

That's awesome! A weekend warrior grabbing the bull by the horns. That's too cool! Ballsy, to say the least. I'll offer any advice I can to help make your project go as smoothly as possible.
Extending the sway bar arms? Upgrading the coil-overs? How much wider are you going, if at all? So many juicy questions I have for you!
So, are you building arms also? I think HCR or Lonestar offers +4 or 5" arms that extend the rear axle centerline back 3". Although I would NEVER recommend moving the axles only back that far, those arms would be right at home w/ the rear diff re-located. Use caution when deciding on how much length to adjust your axles by. Now that they will be properly aligned with the diff, they will plunge much deeper than did the stock axles that were swept back. I believe the minimum amount that you can move back the diff was 7 3/4" or 8" to allow adequate clearance between the inner cv joint bodies and the factory rear control arm pivot bracket that vwertically ties in the parallel tubes. I moved ours 8 1/2" to take full advantage of the rules regarding wheelbase extending. The rear drive shaft will also need to be lenghtened by just under the amount that you moved the diff back.
Also, it was really tight squeezing the diff between the stock paralell tubes that terminate behind the diff. Since you will be removing the lower cross-over tube that ties in the frame behind the diff, you'll need to fab a cross-over support that uses the upper rear control arm pivots as mounting points. Try to design the mod so you can still remove the rear diff by pulling it out from the rear, as per OEM design. It is much more maintenance friendly if you can make it happen. Ours has to drop in from the top, with the fuel cell out. So, to yank my motor or replace a drive shaft, I must first remove a coil over shock from either side, then the fuel cell, then the rear rotors, hubs brakes and axles. Then, that pesky bolt that attatches the driveshaft yolk to the output shaft in the rear diff. Finally, I can pull the diff up from within the fuel cell framework. Fortunately, our robust design never let us down during a race, therefore it has not been an issue.
The tightest squeeze will be fabricating a new rear toe link. Where before, it ran behind the axle, it will now pass underneath the axle. There's room for it to go there, you just have to cycle the suspension and confirm clearances.
Your stock cv joints are good for 25 degrees of reliable deflection when they are properly aligned. You will also notice a significant increase in acceleration, as you have now returned to the rear wheels the horsepower that Can-am robbed from them by sweeping the axles back.
Hope I didn't scare you away from your plans! I'll be here every step of the way for you. Just let me know. Good luck MDD!!

 

[badassmav]

Max frame build

I intend to thoroughly document the early stages of the construction of our 2014 race chassis. The finished frame will look unlike the stock version, yet still be 100% legal. This chronology will provide clear details on how I maintained stock pivot point and motor placement, as outlined in the rulebook.
After unloading our new frame from the freight truck, the first thing that caught my EYE (trust your eyes. They don't lie) was how lax the factory tolerances are for torsional alignment when welding together the frame structure. It is not a coincidence that the new frame is twisted identically to what our current frame is. The Monster Mav was not stripped to the bare bones when the cage work was fab'd, and consequentially, it too has "the OEM twist". Drives me nuts every time I go to do a 4 wheel alignment! Note the yellow box and line up the front and rear tubes it is highlighting. I know, right? I know it's just a UTV frame and all, but a simple analysis of the welded frame, and some minor adjustments in the welding sequence from the manufacturer would solve the issue (assuming their jig is flat). If you have not yet noticed, I am obsessive-compulsive, so bear with me.
Once I remove all of the unwanted structure (everything but the 2 tubes that run parallel to the wheelbase, just inside the body, the lateral tubes that pick up the front and rear motor/transmission mounts, and the two end tubes that connect the longitudal frame rails.), I will straighten the base platform before clamping it onto my frame jig.
So, here's the protocol:
-Position the frame squarely on the welding jig, with indexing for repeatability.
-Pick up the stock suspension pivot points by making a jig that slips into them, and clamps to the main welding jig.
-Remove the frame from the jig, and begin cutting away the undesired frame structure (probably 70% or so of the stock frame)
-Grind SMOOTH (not gouge!) the cut off welds, straighten the base platform, and strip the factory coating by most likely a sand blasting process.
-Re-clamp the base platform onto the frame jig, using the prior indexing references and stops.
-Adjust the squareness of the jigs that picked up the pivot points, as they were attatched to a twisted frame.
I now have my base frame and my suspension pick up points. The base frame is initially clamped to the welding jig using 2" & 3" spacers (front and rear, respectfully) between the car frame and welding jig. This represents the amount of ground clearance I am designing in at full bump.
Now, I can begin designing my space frame based on countless hours of dimensional, weight, ergonomic, aesthetic, structural, service friendly,and performance considerations. The results of these parameters I will numerically keep to myself, as they will be the meat and potatoes of the success (or not) of our build. The subsequent pics will show these features to you, as time permits.
I have offended people in the past by calling our project a "true build" (insinuating that theirs is not, I guess). What I mean by that is I am not just welding in seats, a fuel cell, shock mounts, and light tabs etc., rather I am completely re-designing, selecting, and/or hand fabricating nearly EVERY component of the vehicle to accomplish a pre-determined set of parameters that I feel will maximize the performance and reliability of our car. I would be happy to bolt on aftermarket suspension components, but none seem to fit the bill for our needs. I will develop a tamer version of this build for the masses. It will fall short of the all-out design of the race version, but will not ignore areas that require attention i.e. cv joint deflection, motion ratios of shocks, etc.
Enjoy, and please comment.

 

[BiggJim]

Nice frame table! Ive never seen a bare can am chassis.... I wouldn't have expected the square tube down the middle.

 

[BiggJim]

Re: Max frame build

I would think not many people were so much offended as they were question who's this guy and where did he come from.....either way I would expect that there are more people that want too see the build than not.

With that said....Do the other guys totally redesign the car...not so much....for us redesigning the whole car does not make sense....In the end if we are going to spend the time building a race car and designing parts for it we want to see repeatability without having to tell a potential customer you have to cut your car in-half if you are interested in my product. I would expect that's where a lot of the non "TRUE BUILD" comments may have come from.

Im looking forward to seeing the build pics....bring'em on Brotha!

 

[badassmav]

Nice frame table! Ive never seen a bare can am chassis.... I would have expected the square tube down the middle.

Cool, huh? I'll throw a blanchard ground plate on top when I'm done building the frame, and presto! A 4' x 10' welding bench that is flat AND square!

 

[Factory UTV]

Looking forward to seeing the build, keep it coming for sure!!!

 

[badassmav]

your pics and detailed explanation of why you did it, are very rare in this sport. Most teams keep everything quiet from build materials to their learning pains.

i understand wanting to keep everything quiet but dont forget about us little guys who learn from you and your trials and tribulations.

btw just from your pictures and explanation of how you moved the rear diff back i decided on chopping mine this summer and getting more whelbase.


Thanks BA

Here's a couple of pics on where everything ends up. Note the notches in the rear section to clear the diff. These pics do not show the upper crossover support that is crucilal now that the diff no longer acts as a spreader between the rear suspension pick up points.