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From what little I was told, this was built and raced in the 80s, and has sat more or less untouched ever since. It's never been cleaned or anything.


It has the following aftermarket parts on it:

Hot Trick front and rear A-arms.
Litespeed Litesink.
JG top plate.
JG front bumper.
RC10 (early?) shocks.
Le Mans motor heatsink spacer.
Option House gold nerf bars.
Option House gold motor guard.
Option House belt drive conversion.

The electronics consist of:

MIP Engineered Performance Motor
Futaba FP-S28 Servo
Futaba FP-R2GS Receiver
Novak NESC-4 ESC


Heres how it is right now in as received condition:

That's a neat custom to start with. Do you plan on keeping it on-road or will it return to buggy land?

thats going to be a stunner in the making! love the litesink so buggy or what mate?

It's been able to maintain it's carpet oval form for so many decades, I can't bring myself to change it. It has history behind it this way. I'm just going to take it apart to give everything a thorough cleaning, and then rebuild it back again.

Completely unreal!! Do a full rebuild with pics!

Wow, that definitely is a time capsule CO Optima! I think it is absolutely perfect as is with all the period correct goodies!

Awesome car! It's going to be a beauty!

The body on it has a really nice metallic purple paint job but the right side has gotten damaged over the years from storage. There's a crack in the fender, the side is pushed in (deformed), and there's a crease in front of the rear wheel opening. Its a shame really.

I'm not sure what the motor is as the label is obstructed by the motor guard. Its completely black and has large white lettering on it.

Here's two pictures:

Nice, looking forward to your resto progress! I have to wonder at the cooling efficiency of that heatsink in that particular position, though...I wonder how much heat is transferred away from the motor by the contact point of the shaft-end of the motor? Most heatsinks are positioned close to the can itself, or are mods off of the endbell, where the electrics are located. I could be wrong but it seems the 'sink was simply reversed and placed out-board as the Option House gold motor guard is in the way.

I notice the same issue with my own Optima, there's no easy way to mount a heatsink unless the motor guard is removed. Pargu2000 makes an aluminum part that includes a heatsink, and it's positioned exactly where the motor can/motor guard would be.

I guess it would be easy to test. If you do a run in grass and the motor's getting hot, but the heatsink isn't hot, you know it's not doing it's job.

Coelacanth wrote:Nice, looking forward to your resto progress! I have to wonder at the cooling efficiency of that heatsink in that particular position, though...I wonder how much heat is transferred away from the motor by the contact point of the shaft-end of the motor? Most heatsinks are positioned close to the can itself, or are mods off of the endbell, where the electrics are located. I could be wrong but it seems the 'sink was simply reversed and placed out-board as the Option House gold motor guard is in the way.

I notice the same issue with my own Optima, there's no easy way to mount a heatsink unless the motor guard is removed. Pargu2000 makes an aluminum part that includes a heatsink, and it's positioned exactly where the motor can/motor guard would be.

I guess it would be easy to test. If you do a run in grass and the motor's getting hot, but the heatsink isn't hot, you know it's not doing it's job.

That's good advice.

the heat sink will most definitely do it's job. heat will flow to the coolest parts, and that includes that heatsink.

though the heat is concentrated in the body of the motor, heat will flow through the endbell and into the motor plate.

Coelacanth wrote:... I wonder how much heat is transferred away from the motor by the contact point of the shaft-end of the motor?

You'd be surprised. At a big race this past weekend, a buddy of mine was running a tamiya 501 buggy. While he didn't have an actual heat sink on his motor mount, the mount is made of aluminum When he pulled the car off of the track, the motor mount was hotter than the actual motor. If there were any fins on it, it would get rid of quite a bit of heat.

jwscab wrote:the heat sink will most definitely do it's job. heat will flow to the coolest parts, and that includes that heatsink.

though the heat is concentrated in the body of the motor, heat will flow through the endbell and into the motor plate.

True, but that isn't the most direct, effective path for heat transfer. Sure, it's better than nothing to have a heatsink hanging out that far from where the most heat actually is, but it's not the most effective implementation of the design to have heat pass through the endbell, motor spacer, gearbox sideplate, then the outboard heatsink mount. Just sayin', that's all. I've been overclocking computers since I first pushed a Pentium 166 MMX to 183 MHz and working with heatsinks & airflow is kind of one of my specialties.

The other obvious flaw in that design is, with a heatsink hanging off to one side that far, it's bound to get ripped off by a collision eventually, and possibly result in the whole side-plate getting bent. The attached heatsink design by pargu2000 is a lot more logical--though the motor guard'll have to be removed.

To be honest, I can't recall ever seeing a motor heatsink hanging off to the side like that, immediately behind the drive axle, no less. I stick to my supposition that the part was intended to be mounted behind the motor, but because of the motor guard being in the way, someone did some mounting improvisation.

Although the Litespeed heat sink was intended to be mounted behind the motor to not get torn off (and has been mounted hanging out in space in this application to allow the use of the gold motor guard), for heat transfer purposes, it doesn't really matter. The heat sink doesn't touch the side of the can in either position, relying completely on the conductive heat transfer through the shaft end of the can and motor plate. The best option would be an adjustable sink that was curved and could be placed directly along the side of the motor can to get more surface contact. I had an RC10 motor plate like that BITD and it worked extremely well.

All very good points.

I've never paid specific attention to which side of the plate the actual heatsink part is supposed to go on but I thought this was the standard configuration. I suppose there's not a right or wrong way since the design dictates both. It seems to be left up to the individual to decide. With that being said, I think I'll flip it to the other side to see if it will clear the motor guard. It will be awfully close if it does.