My XO-1 mods

[FartOfDoom]

Bought an XO-1 off of a seller on ebay a couple of weeks ago and I have to say WOW... Seriously??? Not bashing on Traxxas or anything but hmmm... This thing is suppose to go 100+ with all the slop/play everywhere?

The car is now completely stripped and the modding process has begun Time to make this thing a 100+ arrow…



1st the main source of the problem, the front steering block and that funky screw with the the built in bushing? I’m replacing the screw/bushing with 3x6x2.5 flanged bearings. Since it’s a 5mm opening and the smallest OD flanged bearing is 6mm I’m reaming it out to 6mm top and bottom.



Get the best and highest ABEC rated bearings (not ceramic guys) cause it will take some beating @ 100+. You don’t wanna go cheap here cause the last thing you would want this car to fail on you while driving is the steering… Next lathe the steering block down evenly on both top and bottom and you’re done!!!



Add shims in the right places to reduce binding and achieve silky sexy smooth slop free steering!!!



2nd problem arms and pins. Diametor of the pins is 3.16mm while the holes in the arms they're 3.27mm




Ream the holes out to 3.49mm and pick up some 3.5mm shock shafts and cut it down to size




Waiting for a few more parts and more mods coming soon ENJOY

$20 Air cooled 12V .08mah draws with 17cfm 34cfm combined.

[Ghostbuster]

Looks awesome! Keep up the good work!

[AngryEVO8]

what did you use to ream out the castor blocks

[powers]

Where do you get the braided wire covers?

[danielhr77]

Looks very good! "Slop" is something I found in every truck... And, it's fun to fix it...

[FartOfDoom]

put it in a drill press and vise it down with a reamer like this one on ebay

http://www.ebay.co.uk/itm/TECHNICUT-...item4aacf2a72e

and the braided cover got them from fry's electronics.

Cant wait for my ultimate mods. You guys gonna love this

[lcaa]

You guys gonna love this

Can't wait!!

[BennyG6]

what are u using to hold the steering blocks with the bearing carriers after you install the bearings on the steering blocks

[FartOfDoom]

It's actually sandwiched between flanged bearings, 4 bearings total per side, 8 3x6x2.5 flanged total. Lathe the bearing block down at 5 degree angel so there's no binding between the block and outer part of the bearing

[FartOfDoom]

o-rings front and rear center shaft to reduce shaft movement


3x8x2mm washer on the motor mount screw for a better hold

[BennyG6]

pretty slick , and very clean

[danielhr77]

I'm saying it again, I like it!

[X2guy]

Great idea for the front steering. Was thinking of ways to fix this. I have ordered some 1/8 id bronze bushings for the a-arm pivots. I will also be installing them in the bulkheads. The od of the bearings is 3/16 which will weaken the arm slightly so I will be adding a carbon fiber wrap around to strengthen it.
Where did you order your flanged bearings for the steering? The bushings I ordered took three weeks to get. These small sizes are not common.

[X2guy]

I picked up these a-arms thinking they might have addressed some of the slop but no good. I think I may use your 3.5mm shock shaft idea on these. They are slightly thinner than the stock a-arm so thare may not be enough material for the bushings to be fitted.

[FartOfDoom]

The bearings they're Racers Edge

http://www.racers-edge.com/Ball_Bear.../rcet02080.htm

You'll be surprise how mush slop is coming from the pins

[FartOfDoom]

Here's a preview of what's coming


Rear end coming together nicely. Lubed all moving parts with white lithium

[AngryEVO8]

What shock shafts did you use to make the suspension pins?? I dont want to order some only to find out they are too short.

[FartOfDoom]

They're HPI 100950 Shock Shaft 3.5x90mm. It's 90mm so plenty to play with. BTW you're going to need at least 6" #28 .1405" drill bit for the front

[AngryEVO8]

Is that to ream out the bulkhead?? Can you not use an arm reamer

[FartOfDoom]

yep it's for the front bulkhead. The triangle looking part on the front of the bulkhead is too far out for a normal length drill bit

[FartOfDoom]

Here you go guys for the braided wire sleeving. It's the exact one I'm using

http://www.frys.com/product/2281378?...H:MAIN_RSLT_PG

[FartOfDoom]

@ 100+ MPH the foam bumper would be like paper against a bowling ball, so how about a real working front air intake?



Almost done. A few measurements and black paint

[slvr bullet]

very nice work. I am no engineer, but the question I have is all that air coming in the front bumper would it make it unstable at 100+ mph?

[BennyG6]

hopefully we see a meshed out vent hole on the bumper lol

[wirgej38]

love it! very clean...i'd really like to see where this is going!

[FartOfDoom]

yep it will be very unstable @ 100+, the intake will act like a parachute and it will flip very easily. the only solution would be more weights to hold down the front, or canards to product more down force. I'm going with canards and stiffen the front end of the body

[FartOfDoom]

almost done on the intake

[FartOfDoom]

the middle part of the body is pretty weak without any support. so my solution 5th and 6th body post. I'll probably mount it using magnets instead of using body pins and drill a hole. if it flips over the body post wont last too long grinding on pavement

[FartOfDoom]

OMG!!! here's with the body on... looks so aggressive!!!

[FartOfDoom]

finally done with the front canards

[BennyG6]

are you going to cut the rear of the body also ?

[AbSoLooT1]

Wow... That looks MEAN! Def throw down some black mesh on the front for sure, IMO. Thatd looks sic, But great job, and clean work. I too am ALL about removing slop big time. Even on vehicles that dont go anywhere near 100mph. Nice work!

[slvr bullet]

that looks mean... to nice to drive i would make that a shelf queen.

[FartOfDoom]

Thanks guys this car is AWESOME!!! I took it out to my local airfield yesterday and this thing hauls!! This thing comes at you very quickly

With all the mods the car feels like it's on rail most of the time. I did notice a bit of a drag in the rear though, is it because of the body? Anyone notice this?

Looks like it's going back on the table for more mods

[DBG]

Nice build.
I have a question:
What are you using to power the fans?

[AngryEVO8]

It will be interesting to see what you come up with for the rear. Some of the people on the forum have been cutting out the rear section of the shell, same as you have done on the front.

[FartOfDoom]

DBG I'm using 3s 2200mah lipos for the fans. Connect the fans in a parallel configuration and add a plug to make it simple.

I've seen some of the mods where people cut the exhaust sticker right on top of the diffuser for rear vent, I'm cutting the part where it looks like a license plate area right below the lights right in the middle. That's where I'm thinking it's causing the rear drag, and plus it wont mess with the air flow of the rear diffuser.

[TheStenchOfSpeed]

I just did a very similair mod to mine except I used custom gage pins to make the hinges. I had some gage pins made in .130 diameter and also .131. Then I reamed the arms to accept the pins and it really tightened things up. I had over .135 of slop at some of the wheels before and most of that has been eliminated. Made a huge difference. Took me about 3 weeks to get the pins though. If I were more familiar with RC stuff I would have done what you did with the shock shafts.

Also, another thing I noticed when I took it apart to do this.......I had RPM rear control arms. They were distorted (elongated) at the hinge pin and BADLY bent where the shock mounts. This effectively lowered the car and it was worse on one side then the other. I had no idea until I took it apart. In the future I am only using the Traxxas ones because I would rather have them break then bend and cause other problems. I'm not slamming the RPM arms. They are fine on a truck, I just think they probably don't belong on the XO-1.

[TheStenchOfSpeed]

Also, I like your mods but I'm curious why you did the front air dam mod. Where will the air go? I think it's better to force it over the car and use it for downforce then to channel it inside. Maybe I'm missing some stuff you haven't posted.

With body mods I have been doing, I have been able to apply enough downforce to scrape the front end and I don't even use the "high speed splitter" for drag reasons.

[slvr bullet]

maybe you can share how you get that much downforce with the rest of us. I am currently building my xo-1 to get better than 120 mph which is not easy. just keeping it down would be the problem. so far no luck and lots of money wasted on motors