Ofna DM-One Brushless Conversion (DM-1)

[ssspconcepts]

Originally Posted by dangerwr

Gotcha. I will pick up the top plate for the Jammin' buggy. How light is the car compared to a 1/8th buggy? Also, it seems that you knew to upgrade the diffs--will the stock ones not hold up very long under BL?

The stock diffs were plenty robust...I had a spare set of the spiders. I figured I'd use the spiders since I had them handy and they are smoother than the stockers. Not exactly sure, but the car is probably 10-15% lighter than the Jammin buggy-IMO. It is considerably lighter than my BL Jammin CRT, which is set up with the same conversion stuff.

Originally Posted by ssspconcepts

The stock diffs were plenty robust...I had a spare set of the spiders. I figured I'd use the spiders since I had them handy and they are smoother than the stockers. Not exactly sure, but the car is probably 10-15% lighter than the Jammin buggy-IMO. It is considerably lighter than my BL Jammin CRT, which is set up with the same conversion stuff.

Are these the Spiders you are using?
http://www.amainhobbies.com/product_...ducts_id/24323

http://www.amainhobbies.com/product_...ducts_id/24324

Not exactly cheap! I think I can find them on eBay for a bit less. Not sure but will probably run the stock ones in the F/R but replace the center diff with a Spider. You mentioned there was a fit issue or is it a direct fit?

[ssspconcepts]

Originally Posted by dangerwr

Are these the Spiders you are using?
http://www.amainhobbies.com/product_...ducts_id/24323

http://www.amainhobbies.com/product_...ducts_id/24324

Not exactly cheap! I think I can find them on eBay for a bit less. Not sure but will probably run the stock ones in the F/R but replace the center diff with a Spider. You mentioned there was a fit issue or is it a direct fit?

Those are the ones. If you drop in a center diff, you will have to replace your rear center drive shaft with a different size...I have a spare if you need it.

Originally Posted by ssspconcepts

Those are the ones. If you drop in a center diff, you will have to replace your rear center drive shaft with a different size...I have a spare if you need it.

Thanks! I will let you know once I actually get down to it. I am wondering about that solid center shaft that another member posted the link on Tower or the Spider center diff. Is there an advantage to using a true differential over a solid shaft?

[ssspconcepts]

Originally Posted by dangerwr

Thanks! I will let you know once I actually get down to it. I am wondering about that solid center shaft that another member posted the link on Tower or the Spider center diff. Is there an advantage to using a true differential over a solid shaft?

I don't know yet...

My preference is to use either center diffs or trannies with a slipper. Mike's slipperential...when it is released...will do both!

To answer your question...you can simply install the collar that comes with that center solid shaft on the DM-1 stock 2-speed. It should work fine....when you get to that point there are plenty of members here that can help.

[ssspconcepts]

Latest progress:

From DM-1 Spec

From DM-1 Spec

[BrianG]

Originally Posted by dangerwr

...I am wondering about that solid center shaft that another member posted the link on Tower or the Spider center diff. Is there an advantage to using a true differential over a solid shaft?

I personally like the solid shaft. A center diff unloads too much and spins the front tires unnecessarily and you lose power. Unless you put really thick oil, and then where is the benefit? Maybe on a track where cornering is vital, but these have so much power that it's easy to drift around the corner if you want to turn tight.

I don't know what benefit a torsen diff (if that's what you mean by "spider") would offer. I can see using it in the front or rear to keep one side from unloading on corners. But the combination of stiff suspension and sway bars helps that a lot. Otherwise, it kinda acts like a solid shaft if used in the center...

[rchippie]

That looks great . I almost got that car instead of my gtp . Does the battery hang of the chassis much ?.

[ssspconcepts]

Originally Posted by rchippie

That looks great . I almost got that car instead of my gtp . Does the battery hang of the chassis much ?.

It is a really nice kit car...I am continually impressed with the quality of the Ofna products that are available. I guess about 1/3 of the battery hangs off the chassis. The is probably too much for your comfort as I recall from your previous posts a long time ago...but the tray is delrin, and this is a street racer, and everything is bolted down nice and tight...

[ssspconcepts]

Originally Posted by BrianG

I personally like the solid shaft. A center diff unloads too much and spins the front tires unnecessarily and you lose power. Unless you put really thick oil, and then where is the benefit? Maybe on a track where cornering is vital, but these have so much power that it's easy to drift around the corner if you want to turn tight.

I don't know what benefit a torsen diff (if that's what you mean by "spider") would offer. I can see using it in the front or rear to keep one side from unloading on corners. But the combination of stiff suspension and sway bars helps that a lot. Otherwise, it kinda acts like a solid shaft if used in the center...

I used 90wt diff fluid (which was the thickest that I had on hand). I am going to try the diff and then try the center spool. I just wish somebody made a heavy duty center slipper to go with that solid shaft....

[BrianG]

Originally Posted by ssspconcepts

....I just wish somebody made a heavy duty center slipper to go with that solid shaft....

Yeah, that would be nice. But believe me, the tires slip enough. Seriously, I don't think the lack of a slipper is a big deal. Other than controlling take-offs, the other use of a slipper I can think of is to absorb drivetrain shocks when landing from jumps. Do you plan to jump this?

[speedracer1129]

Originally Posted by ssspconcepts

I used 90wt diff fluid (which was the thickest that I had on hand). I am going to try the diff and then try the center spool. I just wish somebody made a heavy duty center slipper to go with that solid shaft....

Are you sure you used the right oil??? That there is shock oil, no good for diffs!!