Project: Optima

[GoMachV]

i had to cut some material today for a customer and decided to keep going while the material was mounted up. I've had these drawn for a while and just acquired a nice parts car to build it from. Here's the basics...

-one piece sides with belt or chain adjustment made at the front trans mount holes
-battery moved forward, can run sideways or if using a lipo shorty will fit north south as shown
-servo will mount in the back, either on one side like a Maxxum or standing up. Haven't decided
-rear shock tower uses modern wing mounts and offers more adjustability
-front tower is Mid geometry for upright shock mounting

Lots of ideas still to go, this is just the test fit

[DennisM]

Beautiful

[Mr. ED]

Have you been sneaking around inside my head? This is something I've been wanting to do for a long time.
Can I see the bottom side?
Say I'd want to get my own design cut by you, could you do it from 2d dwg or dxf files?

[GoMachV]

Sure thing Ed, I can work off either file type.

The bottom isn't don't yet and I haven't decided quite how I want to finish it. The sides are not correct either just place holders haha. I want to keep the bottom narrow, it will likely sweep out at the rear for electronics but there again I may just use a radio plate.

The other thing this opens up is wheelbase adjustments. It would be easy to lengthen it to make a lwb version. With this one the frame rails are intact but for weight savings might as well cut them anyway.

Lastly, this one is 3/32 thick, pretty hefty. I may experiment with some 1/16 and see how it works. Tied with the rails and lower or upper chassis and posts it will likely be just fine.

Hopefully I'll have more time today to play around with it.

[Mr. ED]

I was thinking lwb indeed, and maybe saddle packs too. Then again, why stop halfway ...

[GoMachV]

Indeed!

[Coelacanth]

I'm interested in your project, too. Can you consider some method of adjusting the front shock tower angle, because the original Optima could've used more camber to improve the understeer-on-acceleration issues. The original Optima's only camber comes from the slight kickup angle in the front gearbox and in the C-hubs.

I like how you incorporated a better shock tower with wing mount...both OEM front & rear shock towers were notorious for their weak design and always bending. The front shock tower was always a weak point, especially that middle section where it narrows down.

Another good thing to consider is a way to implement some kind of Lexan under-tray, perhaps one from a LWB Mid.

[GoMachV]

I'm interested in your project, too. Can you consider some method of adjusting the front shock tower angle, because the original Optima could've used more camber to improve the understeer-on-acceleration issues. The original Optima's only camber comes from the slight kickup angle in the front gearbox and in the C-hubs.

I assume you mean Caster, and if so...there isnt a great way to do so. The gearbox would have to tip and then the chain/belt wouldnt enter and exit properly. The kickup in the nose is on-par with most 4wd buggies (although some are completely flat too, like the YZ10) and the carrier does the rest. The two caster blocks that were sold were the only means of changing caster and will probably remain that way on mine (but we can always shapeways different degree blocks)

I like how you incorporated a better shock tower with wing mount...both OEM front & rear shock towers were notorious for their weak design and always bending. The front shock tower was always a weak point, especially that middle section where it narrows down.

yup, that was my goal there too, its not the strongest way of mounting but will be much stronger than stock

Another good thing to consider is a way to implement some kind of Lexan under-tray, perhaps one from a LWB Mid.

im a big fan of the Optima Pro body and tray, which should fit fine. Not sure about others tho. TOMS undertrays should bit with a little work

One thing I didnt mention is the front brace and bumper mount are gonna be gone. Two goals here- most are bent to hell anyway, and I think a plain old race bumper will suit it better anyway. I want those tires to dig if they happen to hit the ground first!

[Phin]

Looks real nice I'm wondering about, and waiting to see, what you're planning for the steering servo.

Lastly, this one is 3/32 thick, pretty hefty. I may experiment with some 1/16 and see how it works. Tied with the rails and lower or upper chassis and posts it will likely be just fine.

I was considering going up to 3/32" for my Radiant chassis plates but after seeing yours I agree that it looks too hefty. The originals aluminum plates on it are 2mm so I'm going to stick with the .08" sheets.

[GoMachV]

Looks real nice I'm wondering about, and waiting to see, what you're planning for the steering servo.

its already drawn, it will either poke out the side at the rear on the left, or stand upright on the tiny radio tray that you havent seen yet (its in my head! lol)
It will be up to the buyer to decide which he prefers. Length of the steering rod will be the same.... long

[Coelacanth]

I'm interested in your project, too. Can you consider some method of adjusting the front shock tower angle, because the original Optima could've used more camber to improve the understeer-on-acceleration issues. The original Optima's only camber comes from the slight kickup angle in the front gearbox and in the C-hubs.

I assume you mean Caster

Yeah, my mistake, I meant caster.

[myfordcnc]

sweet sweet work!

[terry.sc]

I'm interested in your project, too. Can you consider some method of adjusting the front shock tower angle, because the original Optima could've used more caster to improve the understeer-on-acceleration issues. The original Optima's only caster comes from the slight kickup angle in the front gearbox and in the C-hubs.

There are two different C hubs for the Optima, the OT-47 which was used in the first cars, and OT-55 which has more caster angle in them.

Rather than trying to rotate the gearbox, if you want to increase the caster angle the simplest way is to make a new front suspension plate with the pivot pin holes higher to tilt the wishbones.

[GoMachV]

you want to increase the caster angle the simplest way is to make a new front suspension plate with the pivot pin holes higher to tilt the wishbones.

Thats a great idea Terry, and one I will play with. I have seen on the Spyder series they made different rear plates for toe....no reason you couldnt do the exact same in the other direction for caster and even anti squat in the rear if needed

[DennisM]

you want to increase the caster angle the simplest way is to make a new front suspension plate with the pivot pin holes higher to tilt the wishbones.

Thats a great idea Terry, and one I will play with. I have seen on the Spyder series they made different rear plates for toe....no reason you couldnt do the exact same in the other direction for caster and even anti squat in the rear if needed

If the holes in the front pin brace are raised, It needs a bit of widening too - Otherwise the innerpart of the arms are going to rub the gearbox?