Luke's Procat rebuild

[Bormac]

There's some really good info coming out in this thread. Thank you for going to the trouble to explain things in a manner which we can all understand.
Keep up the great work!

[kaszal]

[kaszal]

Broke the rear shock mount too



4mm should be harder to break (thank you Fibre-Lyte)

[kaszal]

I discovered a slight problem with the new outdrives - they interfere with the inside of the front uprights when the crashback goes back. I might dremel a little off and see. Otherwise great upgrade - the diff screw will never come loose and the thrust race and disc springs are completely sealed.

[Jay Dub]

Well, I love your car. It's nice to see someone taking a modern view with these old cars.

Looking at the pictures, I think you should limit the rear travel a little, and increase your front a bit. First question however is are you all the way out on the rear arm with the bottom of the shock? If not, then just move it out. This could solve several of the previously mentioned issues (oil/spring increase, and limiting travel) . Give it a go and let us know. -Jeff

[kaszal]

Thanks Jeff

It's on No. 3 at the moment so I'll move it out to No. 2

There are short ball-cups on the front shocks (the normal ones give too much travel) but I could undo them a couple mm.

[Jay Dub]

Cool, yeah move them out a hole on the rear. Undo the front a turn or two and see how you like it. As a general rule of thumb, I will setup the droop on a new 4wd car with the centerline from axle to axle just below the chassis (flush with bottom or 1-2mm). This is usually a good starting point, and can be tuned from there.

One thing I have been looking at on my car it the possibility of adding spacers under the ball studs on the bosscat front hubs top and bottom. This will move the axle down, without the need to add droop in the suspension (via lengthening the shocks). This will give a more supple suspension through rough corners. I think it just needs a little grinding on the hub. I am considering doing this because the diameter of the Schumacher universals requires that they be high in relation to the suspension pivot point. Because of this, the suspension requires more droop to get the right amount of wheel droop. -Jeff

[kaszal]

OK dropped the front a little, raised the rear and dremelled the front uprights.

Here's the list of everything I've changed on the car....

Fibre-Lyte carbon fibre parts:
- PROCAT 01 and BOSS 04
- PROCAT 02 in 3mm carbon (stiffens chassis)
- BOSS 03 in 4mm carbon (extra durability)
- custom battery trays and straps
- custom under-chassis strips (add stiffness and prevent screws splitting undertray)
U858B Bosscat 23mm pro-diff with alloy washer carriers:
- U1631 23mm diff output yokes (need to dremel inside of front uprights T156)
- U857 diff screw, springs, locknut and cover – tip: arrange springs )()(
- high tensile M3 × 45 cap head diff screw
- 3mm ceramic diff balls
MMS machined nylon front diff
U194 hi torque drive belts - 5mm
Bud’s Racing Products #6510 ultra drive belt
Bosscat slipper clutch, RW Racing 90T Supalite spur 90T and 19T pinion
custom laser cut red anodized gearbox side-plates
alloy eccentric bearing housings, inner transmission housing and Z bracket
Wasp Racing ballraced steering and PK Racing alloy track rod
rear anti-roll bar
Lunsford titanium turnbuckles (3 pairs), ball studs and motor screws
Bosscat rear hub carriers and 1/8 pin wishbones
Bosscat H-bracket (sanded to fit)
crash-back o-rings from eBay 0.862 × 0.103”
54028 TRF buggy aeration oil filled dampers
- Front: drilled pistons 2 × 1.1mm, 40wt oil, AE blue springs 4.2 rate
- Rear: pistons 2 × 1.3mm, 35wt oil, Losi pink springs 2.3 rate, 5mm downstop spacers, dirt shields
RW Racing #575 Yokomo wheel adaptors and JC Racing YZ10 dish wheels
U1042 aerial mount – universal
socket head screws mostly from http://www.modelfixings.co.uk
BMS-621MG and Kimbrough servo saver
Novak GTB and Velociti 5.5 motor
6.6v 3800mAh 60C Orion Li-Fe battery
Team Bluegroove Procat shell and undertray (paint by RCS Graphic Worx)
HPI #61524 EU wing set
U3298 Schumacher wing mount - off road

Other modifications and tips...

vulnerable areas of undertray and shell cushioned with sponge tape
undertray and belt cover sealed with foam tape to keep dirt out of transmission
diff washers sanded with 600 wet and dry
front gearbox screws replaced with four M3 × 40 countersunk bolts
front belt tensioner removed and spacers inserted behind gearbox brackets
screws for rear wishbone brackets replaced with single threaded bolt (RW Racing)
front anti-roll bar mounted underneath top deck so does not rub belt or cover
front one-way drive shafts replaced with normal drive shafts
grub screw secures hinge-pin in front top wishbone
extra weight added under servo and steering
front hub ball-joints spun in Dremel tool and polished with Brasso
extra spacers inserted under hub ball-joint to reduce bump-steer
wishbones shimmed to reduce slop

Don't think much is left of the original

[kaszal]

Here are some close ups of the modified uprights and also the spacers that move the gearbox back to keep the belt tight.

[kaszal]

Can anyone help me find an electronic version of the Bosscat Works manual?

Cheers

[moozo]

Luke whats it for as i have one that i could photo copy and send you if you like, although i think its the team version, does it matter?

Mick

[kaszal]

Thanks Mick, that would be great.

It's the rear suspension I'm interested in particular but I'm curious about any other differences too.

I hope it's not too much bother... at work we have a photocopier that scans a booklet to PDF in a flash!

[moozo]

No bother at all, but this manual wont show you the differences between the team version and the works version, or are you meaning the differences between the bosscat and procat????

[kaszal]

Didn't the works version have different rear hubs carriers and bearings?

[Jay Dub]

Yes, the works version had longer rear arms, and smaller rear hubs (with smaller flanged bearings). The tie rod mounting point was also further tward the wheel which would change your camber gain. -Jeff