Sunday 9 November 2014

11-Nov-2014, all paid off !

The car was incredible with the 7 degree caster blocks. I was finally able to drive it really well and keep with modern cars. The tail wasn't swinging anymore.
 

Friday 7 November 2014

Adding caster to front

I have changed back to ball diffs, because the geardiffs don't seem so smooth. Since I did not have enough parts to rebuild a rear ball diff, I made some improvements to the standard kyosho rear ball diff.
I got a 8x16x5 bearing, and got my machine shop to make a 16mm sleeve with 19.8mm outer diameter.


 
The bearing slides into the geardiff casing

 
This ball diff is now very smooth.
I also used Lazer ZX-5 7 degree c hubs with 3racing ver2 ZX-5 alloy knuckles. I had to grind the c hubs in the fronts to make sure it will fit into the arms without binding. I am in the process of making a ZX arm that will be a direct fit with ZX-5 c hubs.
7 degree caster blocks with 3 degrees in the arm mounts equal 10 degrees total. this should improve handling. However I find that steering throw is also reduced.
Assembled parts. The front CVD is 3racings 65.5mm and upper turnbuckle is now 50mm.
                                   
Grind the c hub below the angle mark. With my new arms which will be ready next week, no modifications will be needed.

 


Wednesday 3 September 2014

Ready for racing - 2014

After cleaning up. Some sand went in the front gearbox and made its way to the back. I changed new gearbox so that it will hold better on the chassis.

Serviced LWB next to my SWB

Monday 25 August 2014

Built a SWB Optima Mid - finally !

This was my brother's old Turbo Optima Mid, that was in pieces.
I have a LWB ,but I missed driving a SWB, so I decided to rebuild one with some upgrades.
My Own Made associated B4 slipper compatible layshaft. More is available for sale.

The loose parts layed out
 

The front & rear ball diffs and rear gearbox innards. Notice my own made hard PEEK gear. I have more for sale.

Semi completed

Assembled gearbox and slipper.


With 2.2" wheels

Kyosho GP10 strong steering parts.

Incomplete rear end

Grinded arms, flipped, to make sure CVDs exit straight

semi complete

Recently completed with Mid SE decals




 
This is a video of this car running, hadn't had a chance to test it offroad yet.
After the ball diffs get gritty I will install gear diffs to cut down maintenance.
next build, my Old Lazer ZX !

Sunday 1 June 2014

Raced my mid today

So finally there is a EP offroad race in MYMTRG track. Unfortunately there wasn't enough entrants so all the EP 1/10 rc vehicles had to be raced together. In the field were 2 Durango DEX 410s, 2 Losi 22s, and one 2WD SCT. On Saturday, the track was mildly muddy, so I decided to use OT-66 tyres. It wasn't a really good race as I did not have any practice these last two weeks. The car kept overturning easily in the ruts as it seemed like the spikes were digging in too much in the bumps. However I finished the race without damage to the car, except the gear cover. I managed 5 laps in 5.08 which netted me in 3rd place for the first heat. Suddenly my boss called me and ask me to haul my butt to work. So I had no choice but to leave the 2nd and 3rd heat. Sure enough some one else beat my time and I slid down to 5th.



On Sunday, I used Lazer ZX-R tyres, figuring that the track was still damp and the hard spikes will dig in well. In the first final I did not do so well, but better than Saturday. I still made 5 laps , and cut down my time to 5.02 which netted me a 3rd place behind a TLR22. Still not happy with the car overturning, I increased negative camber on all 4 wheels, I surmise this would help prevent the car from overturning in the ruts. I also tightened up the slipper clutch to gain more speed and changed my driving style to go easy on throttle coming out of the corners, then gradually increasing speed. It paid off in spades and I cut down my best lap time down by 6s. I also finished 6 laps this time. In the 3rd heat I manage to repeat my performance. 2 finals were tallied and I won 2nd place behind a DEX410 driven by a young guy name dragon. I was really happy with my Optima Mids performance , and the new arms and PEEK c hubs I made were really strong and did not fail even though I took some pretty nasty hits. The Optima Mid has gained the respect from the newer generation after this race. The young guys were surprised with its performance and silence. 
 
 
 

Monday 24 March 2014

Gear Diffs Yet Again

My rear ball diff failed on me last sunday while batting a Durango DEX410, embarrassingly. I really believed I could have at least  kept up with the DEX410 if my diffs were working. I am now installing gear diffs in my MID. I used Xray TC 300,000 gear diff oil filled only half. I did this to make sure the diff wont unload too easily and also the pressure in the casing will not be too high and cause the oil to leak out. I tried this and the diff is quite hard but still movable. The silicone oil should ensure that the setting remains constant and wont loosen up. For the front gear diff I used RIDE TC putty, to make the front diff almost like a spool, just the way I like the car to handle, very stable.
I will let you know how it goes. I hope the large bevel gear will not separate out from the shaft, or I would have to take the car apart yet again...

Wednesday 5 February 2014

Latest updates and changes-Back to Lazer ?

I just recently got a new batch of layshafts , and I haven't been running my optima mid since last year, when I sold my layshaft to Daniel Rowlands. My car has been running for some time now with the optima mid suspension, with the back arms flipped so that I can place the shocks behind the wheel in order to clear the layshafts.
Last night while I was looking my car over I noticed that the rear CVDs were exiting the diffs at an angle, it was swept forward. That means the wheelbase was also reduced about 5mm. There was also noticeably a huge amount of rear toe in, which isn't really a bad thing.
However, the forward swept CVDs could pose a problem.
Forward swept CVDs will pull the rear suspension down under acceleration, and rearward swept will push the rear up, both conditions are not good for optimum handling. I did find my rear end washing out every now then. I then tried placing back the Lazer rear arms, and sure enough, they exited straight as an arrow. If you remember , I had problems with snapping my Lazer front C hubs, so in order for me to use back the Lazer arms, I had to find stronger alloy c hubs. An idea just came to me, why not find drift car alloy c hubs, since touring and drift cars uses smaller components similar to the lazer and optima, I am bound to be able to find one that fits, then I would have to use the knuckles  that fits that c hub.
The MPP arms seem to be tougher than Kyosho arms, simply because MPP arms are more flexible. I don't know how that will affect handling, but for sure my car will be more trouble free. I have been hearing from other people in the know, like terry sc who swears the Lazers suspension is much better than the Optimas on rough tracks, so that's one of the reasons I want to switch back.
However, I did find a peculiar thing comparing lazer and optima arms. The shock mounting holes on the lazer arms are much further outwards. I believe they did this to get back the same wheel rate as the optima since Lazer arms are much longer and will give more leverage. Still I wonder if the wheel rate on the lazer arms is enough for rough tracks, as I believe the optimas shock positioning should give a softer suspension which will handle bouncing better. well, time for testing then.

Another thing I found out about kyosho big bores is the kyosho rod ends seem to be rather weak. I used X ray T2 touring car rod ends with their balls and they are much tougher, but they cannot go into the lazers capped arm because they are 5.5mm wide, compared to the kyoshos which are just 5mm. Anyway, I will try using back the kyosho pieces but this time I wont be removing them so often, and will put threadlock on them.
I will keep you guys updated on my front c hub findings.