Help creating a low budget Hyper 7 brushless

[simplechamp]

I think you'll find that some heavy silicone oil will work much better than the grease at keeping the CD from unloading.

[DrKnow65]

Thanks SC,
One of the items I ordered last night was some 500,000ct diff oil :-) Along with 5 & 7K diff oil, Ofna belted tires, Ofna Inch up rims, a JConcepts Illusion body (no nitro holes), Chrome paint, 6.5mm Castle Connectors, battery straps, glue, and some small bits and pieces.

[DrKnow65]

Update: I've been running the car for a few weeks now. The diffs ended up all being dry aside from assembly lube (funny what you don't need running nitro), they are currently 7K,500K,5K what a HUGE improvement!

I also received my Mamba XL and have started looking at the new layout. Seems that the rear diff relocation will have to wait until I begin fabbing a new chassis.

[IMG][/IMG]

The XL really is extra large...
[IMG][/IMG]

[simplechamp]

What's the full RTR weight on that thing?

[DrKnow65]

Dunno exactly, but I believe in it's previous state, with the MMM, it was right at 10.2lbs ready to run. At first I was concerned about the weight, but after running it on even 6S it is in need of all the traction I can muster. With the XL and swapping the motor forward I hope to shift even more mass twards the front end. As it is the front tires barley contact the ground on acceleration, at 8S it will be even more aggressive.

I'll try to run it over to the post office after the XL is in and get the exact weight.

[simplechamp]

Better start building a stockpile of diff gears and CVDs. Thing looks like it would eat hardened steel and sh*t Integy aluminum LOL!

[lincpimp]

Man, space is a premium on that chassis!!! Where are you going to stick the steering servo? Looking good, what speed do you plan to gear this beast for? 80mph?!?!?!?!

[DrKnow65]

Linc, the steering servo is under the front driveline, the RCM mount sits a little high providing enough space :-) I'd say finding a spot for the servo was the most difficult thing so far.

I'll take a few more pics and a video tonight, it's not actually all that tight in there. I tried to leave plenty of room around the XL and 1518 for air flow, when you look through the front window (cut out) on the body you can see right out the back on either side of the shock tower...

I haven't got into gearing much as I'm going to rely on the data logging and temps for the best ratio. I may be looking into a 1527 1.5d sooner than later to get everything I'm after. Should know after a bunch of test and tune this weekend.

[reno911]

DrKnow after reading the OP title I say this is no longer of those means. Looks more like an insanely, crazy, lets blow up some gears build to me. With that power system I would say get yourself some solid chunks of rubber on the wheels, no ballooning, plenty of power to move it. I hope to see some driveline carnage that no other system has caused before. I am thinking I would like to see some twisted shafts, or teeth through a diff case, something along those lines would make me happy.

Anyways, stellar build and happy thrashings!

[DrKnow65]

Reno, I know the thread title makes it seem like I don't have an idea of how to accomplish the goal but I am realy more looking to the gents here on the forum to watch my progress and offer helpful advise (like simplechamp suggesting silicone oil vs. The grease I thought would be sufficient). At this point the car is driveable, but no where near complete, so I will still need gobs of advise as it progress'.

I still want to make a custom chassis and shift around the components as the motor and XL are pretty high above COG and it's not as weight forward as I think it may need to be.

[reno911]

Originally Posted by DrKnow65

Reno, I know the thread title makes it seem like I don't have an idea of how to accomplish the goal but I am realy more looking to the gents here on the forum to watch my progress and offer helpful advise (like simplechamp suggesting silicone oil vs. The grease I thought would be sufficient). At this point the car is driveable, but no where near complete, so I will still need gobs of advise as it progress'.

I still want to make a custom chassis and shift around the components as the motor and XL are pretty high above COG and it's not as weight forward as I think it may need to be.

Don't get me wrong I was trying to come off with a funny, not trying to be rude. The build looks awesome. I love that you brave the 1/5 scale system in a buggy.

I was thinking that another place to mount the servo could be on top of the steering post mount. May not help with mounting a body, but should work.

[lincpimp]

Originally Posted by DrKnow65

I still want to make a custom chassis and shift around the components as the motor and XL are pretty high above COG and it's not as weight forward as I think it may need to be.

Not alot of real estate on a buggy chassis, you have a pretty good layout, IMO. I doubt you will be able to re-arrange the components to get any more weight forward.

Having the motor up high does hurt the cg, but if you want to run dual battery trays it is about your only option. If you wanted to stretch the chassis and put both trays in the front and have the motor behind one tray nad the esc behind the other you could get the cg down. But you would have a truggy + long chassis.

Only thing I can see to help front weight bias would be to move the battery trays as far forward as you can, but considering the motor is up front I doubt it will make that much difference.

[DrKnow65]

Reno, no worries :-) I wasn't offended, just putting it out there that I'm looking to others for wisdom.

As for blowing up diffs and such it seems to me that lots of guys are running ofna drivetrain parts in much larger vehicles with alot of success, so I'm hoping to have a fairly reliable 1/8th with a minimum of upgraded parts... I hope

[DrKnow65]

I took it out for the maiden voyage (caught on camera of course), it halls well in icy mud gravel type stuff very rough surface and it was all over the place. The rear shocks are way too stiff, which I think is a combination of the 40wt oil, small orifaces, and the 10'f temps here. It does illustrate that I did manage to shift some of the weight farther forward

I was in a hurry to get some video before the sun went completley down, and managed to pull it off (thanks to my long suffering wife ) I'm working on the whole "how to post video's on youtube" thing right now, and should have my shame posted for the world to see shortly.

"Shame" you ask?

The video ends with a busted car seems that one of the rear dogbones managed to find it's way out of the car and into the great beyond. We looked and looked (and even determined the exact moment it lost the dogbone via the video) but were unable to turn it up... fate would have it as well that tomorrow it is supposed to snow, go figure

Video will be here momentarily

Ah that's too bad about the lost dog bone, always seems impossible to find any RC part that flies off, today I lost a Baja wheel for about 15 minutes

Sounds like it's running good though, once you get the suspension dialed in it will be one crazy beast of a buggy I'm sure. Can't wait for the video.