808 is out! >First conversion gets a prize :-)

Well, I am just finishing up my 808 today. What do I win? I apologize ahead of time for the poor pic. I think the photoshopped one earlier is probably better quality. I will snap some more with a decent camera once I get to work tomorrow. This one was with a built in cam on my notebook

I swapped over my setup from the previous XB8/XT8 conversions. This is a MM/Neu 1512 2.5D/Flightpower 4s 5000mAh. The RCM motor mount will work, but it takes some additional work to fit. First, the center diff is offset closer to the right side of the vehicle and this causes the right side guard and chassis to interfere with the motor mount and motor. I removed the third mounting screw/net from the side guard and removed some material from the side guard. I also ran a 1mm bulkhead shim to raise the mount above the chassis' raised edge.

Second, the diff height in the RCM mount is designed to work with the tall center bulkhead of the XB8EC and XT8. The 808 uses a much shorter mount. I couldn't find my spare center bulkhead, so I just used some of the 1mm bulkhead shims from XRAY(#354032) to raise the height even. In fact, I always have used one set of these shims under both bulkhead pieces to raise the motor slightly off the chassis.

In my previous conversions I have tried to use as few custom pieces as possible so anyone else can go out and purchase the same items to do their own. This one is no different. I used the same RCM battery tray, and used two existing holes in the chassis (exhaust pipe mount and engine mount hole) to attached it to the car. I actually use two exhaust pipe mount stands to secure it to the chassis. I also used some foam under the inner edge of the battery tray to keep it secure in the chassis. I have the battery a bit further forward than I would ideally like too, but to use exist holes some compromises were made. I will probably push the battery as far rearward in the box to compensate. This will probably require some setup adjustments compared to a nitro setup, but steering shouldn't be an issue In addition, I wanted to get the ESC as low on the chassis as possible, and the only spot possible is behind the battery tray.

I will probably get the car on the track this week some time, just need to get the body painted up and mounted. More info to come!

[jhautz]

Looks good!!! Some better pics are definitely needed though. I want to see a top view to see how the battery lays out. What motor are you using and gearing are you starting with? The 808 looks to have a much lower overall gear ratio than the old EC and TQ buggies.

Good info on the center dif mount being shorter, I was half expecting that based on the smaller 42T spur and a different part number for the dif mount, so I have an EC center dif mount here waiting for it to use with the RCM mount.

Very interested to hear how it drives. I'm still waiting for my kit to arrive. It should hit the door here on Thursday this week. They just shipped on Friday from the USA distributor to the hobby stores. Then I have to wait until it gets from the hobby shop I ordered from until it gets to my house. I am planning to have mine done next weekend, and I'm really looking forward to it.

Same as you. Just transferring the electronics out of the EC and into the 808.

Any other useful info or tidbits that I might want to be prepared for, or is everything else fairly straight forward?

BTW... I'm very jealous right now.

Yeah, I am sorry about the pic! I should have some better ones tomorrow. I got mine from the US distributor too; but I work there so I get to measure shipping times in minutes to drive home instead of days to ship!

The diff height is a pretty easy fix. You can use several shims like I did to raise the 808 mount to match. I think it is about 3mm shorter than the RCM Mount. I will use the XT8 diff mount, #354011, once I find mine! Then I will only have one 1mm shim under each tower to add clearance for the motor. Ideally, I will probably talk to a local buddy to make a new mount that raises the motor relative to the actual diff and the bottom of the mount. If I decide to use the stock steel 42T gear, then I could keep the diff as low as possible in the chassis.

The new gearing for the 808 creates some options/problems. The new gears in the 808 give you a 43/10 ring and pinion. Th stock 808 nitro gearing is 42T/16T for the spur/clutch bell which is a bit taller than the previous XRAYs. This is probably due to the lighter weight and improved acceleration allowing for taller gearing. In the past, I have used the composite 46T diff gears on my XB8 conversion. I have spent most of my time at a small, indoor electric only track, so the metal on metal noise with the stock steel spur gears was pretty obnoxious. If I try to use the 46T gears for the 808, I am going to need to add about 4 teeth to get back to a similar final drive ratio. That would put me at 18/46 for the small 1/10th track I have been running at. For a larger 1/8th track, I may have to go even higher! The problem with this it it puts the motor way out to the edge and clearance with the side guard may be an issue.

Moving the motor out wide may help with the balance though. Currently with the 4s 5000mAh and Mamba Max on the left side, and the 1512 and receiver on the right side, I am heavy on the left! Moving the weight of the 1512 out on the edge may help counter that without placing additional weight to the right. I have also been considering a lighter 3S/1509 combo, and the 808 would probably be a great candidate due to its lighter weight. This would also help with the balance, removing more weight from the left side. The spur gear is currently the limiting factor for how close to the center I can mount battery. If I am will to deal with the noise, dropping to the stock 42, or the optional 41T spur gear will allow me to move the battery closer to the center. I may try this first since it is quite a bit less expensive than a Neu motor and new 3s battery just to test! I could also mount the ESC on an elevated mount off of the center diff, but I would like to keep the CG as low as possible.

As far as build tips, I don't have anything that sticks out. XRAY has released a tip to remove the inner seal on the pinion gear inner bearing. That tip is listed on their site. Other than that, the kit just falls together like all XRAY kits. I usually build my shocks and diffs first so I can get the messy part out of the way! Rocco should be posting his current base setup on the XRAY site if you want a guide to base your initial setup on. He has been working on a good base setup that is easy to drive. The team continues to test and adjust their setups as they get more time with the cars, so that may vary from the kit setup as we continue to learn about the 808. My previous 4S/1512 setup was within a couple ounces of the nitro counterpart, so I was able to use a similar setup to the team with pretty good results.

Bryan

[Dafni]

Well, congrats, Backfire! You earned yourself a paintjob!

2 things though:
-I only stock EC/TQ bodies, no 808 yet. The EC bodies are a bit wider. Is this okay for you? (I don't know when I get 808 bodies in)
-I can't promise to do it straight away, still got a couple other bodies to finish first.

If you have no other request, you'll get the same design as Mikes RC8. But with a BL808 logo instead of the RC-Monster one. Watcha think?
http://rc-dc.ch/gallery/displayimage.php?album=18&pos=2

[jhautz]

Daf... I'll gladly pay you for a nice painted body, but I will wait untill the 808 bodies come in. I'll run one of my hack paint jobs on the stock shell untill I can get a nice one from you. Actually... now that I think about it, a paint job that would go with the Revo Desert Rat you did for me would be very sweet.

let me know if you can get it one the waiting list.

[Dafni]

Why yes! Of course I can give an 808 your DesertRat treatment, would be MY pleasure... if only the dollar would rise again. At the moment, for me, selling to the states is not attractive at all. But I'll do it for you anyway, Jeff, always.

I hope JConc or PL will release an 808 body soon... the XRay 808 bodies look hideous, especially when they are unpainted. With the right sceme they look alright.

Drop me a PM Jeff, in a couple days... I'll check when I get the XRay bodies.

Cheers
Daf

Here are a couple more pics of the conversion. You can see the additional shims I had to use with the stock 808 center diff mount. I am swapping the 354011 XT8 mount in the car tonight, so I will only have one shim on each side. Weighed the car today without body, and it was about 7.2lbs. A nitro 808 without body was about 7.1lbs, so they are pretty close with the current equipment. The nitro car did have Crimefighters on it though, so I don't know if those are heavier than the Holeshots I had mounted.

[rschoi_75]

looking good man.

[DRIFT_BUGGY]

Well done Backfire, looks great

[DRIFT_BUGGY]

Here is another 808 Brushless Job on RCTECH
http://www.rctech.net/forum/showpost...postcount=5873

[jhautz]

Dang drift_buggy... I was just going to post those and here you went and beat me to it. Thats mine. Ran it today for the first time. LOVE IT. The new 808 just feels like a precision instrument. Absolutely the smoothest, easiest to drive buggy I have ever touched. Freakishly light at only 7.18lbs ready to run with battery and body. Over a full pound lighter than my XB8EC.

I used a EC center diff mount so it was the same height as the RCM motor mount. But I got a note from Mike a day or so ago and he said he has a new Xray mount comming out very soon for the 808. The right height for the lower center dif mounts and slots long enough for low tooth pinions and the 42T center gear. Also a cool new feature will be its 2 piece, meaning that you can take the top half off like the stock diff mounts making it easy to get to the center dif for service without taking out the wholee motor mount and motor assembly like with the current motor mounts. I'll be upgrading when it comes out.

Specs:
Xray XB808
RC-Monster Xray mount and servo tray
Custom made CF battery tray
Neu 1512/2.5d
Tekin R1Pro
5s 4350mah PQ lipos
Geared 42/15 (about 40mph)

DAF... what does second place get? (kidding)


Heres my pics:

[DRIFT_BUGGY]

Like the look of the carbon, nice work

[jhautz]

Sortened up some of the excess wire and fitted a body I had on my XB8EC so I could run it today. (Still need to paint the 808 body) I reweighed it after and heres a couple pics of it on the scale.

One picture with the battery totally reay to run. And one without the 5s 4350mah battery.

I still cant get over how light this thing is.

[Arct1k]

Jeff - your could save almost 2.5oz by going for a 1509 I'm sure it would still have enough torque - Also direct solder the motor leads to save the connectors - must be another oz.... That should take you to under 7...

[Serum]

that's a light buggy for sure!