Homebrew .21 conversion

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Hardcore RCTalk User
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Charlotte, NC
RC Driving Style
  1. Bashing
  2. Racing
I have just started planning my own .21 conversion.

I have been looking to upgrade my engine for a while now and was going to get a OS .15, but I see so many .21s around that now I think that I want to try one out for myself. I will probably get an Ofna Hyper 21 because it is the same price as the OS .15 I would have got and it would be within my budget.
The first step is to make some chassis extenders out of aluminum or stainless steel. The steel, even though it would be heavier, should stand up to the abuse the rear end gets and I may try that first. The only other thing to tackle is the drive shaft from the tranny. I know the stock shafts are too short to use so I had to look elsewhere. I studied some .21 conversion kits and found that some of them use plastic sliders. They are about the same length of the sliders that go to the wheels. I have several stock sliders handy, so what I plan here is to use a stock slider, cut it down if necessary, and then install a dowel in the center of it as seen on Maxxtraxx's tech tips. I hope that this will all cost me under $200 to do.
I will definately get pics of this when complete.
I think I'm going to scrap this idea in favor of a good .15

Thanks for looking guys.
I've seen that kit RCNitro, and I wan't too thrilled about that custom header and the angled pipe. Thanks for the linkage though!
If you're going to extend your chassis I would suggest extending it from the rear because the engine needs more space rather than anything up front. As far as the longer drive shafts the 21 kit I bought uses the wheel drive shafts for the rear drive shaft but since the tranny has not moved you use your front stock drive shaft. Just an approach you might not have looked at.
El Pirata,

I already have a drive shaft built for this using the stock sliders that go to the wheels. It looks like it would work perfectly. I was going to make 2 plates to extend the chassis in the rear.

I don't think I'm going to go through with this this year because I'm getting a used OS .15 from a friend that is getting out of nitro.

Thanks for the input. :)