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I installed my mystery black can motor (brushed) in my Turbo Optima and man, that thing is fast! I was using a 25-year-old 6-cell matched Sanyo pack and I was surprised at how fast the car accelerated. I don't really know any specifics about the motor as there's no sticker on the can, and the only thing inside is "14" and "1" handwritten on the armature. 14T x 1, I guess. I'm almost worried how fast it's going to run with a new 8.4V DTX4600 battery in it!

The problem I noticed--running on pavement with tires I figured were suitable for pavement (see pic)--under hard acceleration, the front tires aren't "hooking up" enough, with the result that the car makes a wide, sweeping turn instead of a tighter turn. To a degree that's understandable and expected, and probably won't happen on dirt or sand or carpet nearly as much...but on pavement, what are some tweaks you guys would recommend to get the front end to "stick" better under full throttle?

Thanks!

Maybe softer front springs?

They're already pretty soft. But since hard acceleration tends to lift the front end, I'm not sure if that would help. It certainly turns quickly when I let off the 'gas'. Thanks for the tip, I'll give it a try all the same.

EDIT: Looking at my own picture, I wonder if the relatively rounded face of the front tires might not be putting a lot of surface area on the pavement. I might try a flatter tire...

smaller or no rear wing. or maybe ad a front wing.

i was running a wingless rc10 in the parking lot next to my house. it would spin if i turned too hard at wide open throttle. i added a rear wing and next thing i knew i lost all steering and ended up running it into a curb.

quick and easy idea so its worth a shot.

LowClassCC wrote:smaller or no rear wing. or maybe ad a front wing.

I almost joked about adding a front wing in my first post... Good idea, I wonder how I'd go about doing that?

grab a soda bottle and some scissors.. cut out a piece of the plastic bottle and attach it to the front nose screws. fold it back and attach it to the upper front shock mounts. a soda bottle is cheap enough so you can mess up and also try different sizes with little money. plus you wont get thirsty while playing around with it

Since most of the weight is at the rear, these cars can be hard to tune. I would suggest removing the front stabilizer bar.

stiffen up the rear springs, and shift as much weight forward as you can.

antisquat may also help, but it might be difficult to implement.

reduce some rear toe if you can.

Some good advice I wouldn't have considered...thanks guys, I'll do more tweaking and update this thread. Keep your suggestions coming.

Definitely ditch the rear wing. Back in the day, I always ran my Turbo Optima on pavement with a stock TO body and no wing; it had very neutral steering.

If that doesn't work, you could go with an Optima Pro radio plate, which moves the battery forward, or make your own plate that does the same thing.

When you go to that high capacity battery just zip tie an extra 6 cell nicad to that front bumper(that's what i do with my pumpkin). Keeps the front end down and steering sharp under big power. looks like crap, but you won't be able to tell thru your huge grin. Then just cut the ties and your back to beautiful for shelf duty.

Ive run my Optima on a few off road tracks and there are some pretty simple things you can do as mentioned above. By the way this car is quite a short wheelbase so should turn in quite well as standard.

Firstly I'd lose the front roll bar because this will 'wash' off some of the steering. Also those tyres almost look like hard plastic- ( am I correct?) Racers yse different rubber compounds aswell as tread patterns to alter handling characteristics.

If you still want more steering I'd soften the front shocks and run the rear stiffer. Even lower the front ride height and raise the rear.

To be honest Its probably just the tyres. I wish you luck.

Increse the Roll center. Top Rear camber link on the shock tower. Has 3 positions so thats the highest on.

Try that than if want more steering raise the rear ride height. Changes the balance to the the front a little more.

As Bormac metioned those 3 racing tires are junk so grip won't be good.

Thanks for all the advice, guys. I stiffened the rear shocks a tad. The tire rubber I was using were indeed on the hard side. I put my Pirate wheels & tires back on, those tires are much softer and I assume more grippy. I assume because I'm dealing with another issue now--I can't keep my right-side wheels on! I don't know if it's the torque of my mystery black can motor or what, but the 4mm lock nuts just whiz off--often the drive hexes too.

My understanding of the stock design is that the only thing keeping the drive hexes from spinning freely on the shafts is the pressing-in of the wider hole onto the angled part of the shafts. That may not be enough for a high-performance, high-torque motor. I've already ordered a set of hexes that lock on with set screws and pins, and will eventually upgrade to CVDs with holes for the pins.

I just can't seem to recall ever having problems with my wheels coming off, in the past...weird.