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Sirio 18, P2, or .21 conversion?

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Hypedonrc

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  1. Bashing
  2. Racing
Can't dicide!

I always hear good things about the Sirio 18. Are th P2's still having problems? Should I bite the bullet and buy a .21 conversion?
 
Depends how much $ you have. But once you go 21, it's very rare that you go back!

Just if you do go 21, doing the conversion is probably better since it lengthens the chassis and allows you to put whatever 21-27 you want in the maxx. Also, if you go with anything over 2hp, I strongly suggest you address the drivetrain. CVD's, RRP steel gears in the trans, proper shimming of the diffs (maximizer or kippster diff cups as well).

Although, I did just recently build a 15 sport maxx that I've been having a ton of fun with. Since it's 2 wheel drive, and I don't really care about the engine, it's fun! But with all the $ I have wrapped up in the 21 maxx, it just sits there until I really feel like laying down some power.
 
I found a Hardcore .21 conv for $165 on the back shelf of a lhs today, and was thinking of the O.S. rg.

Other than cvd's in the front (because they broke, and soon to be all the way around)my maxx is pretty much stock.

As a bashing mobile I wonder if a Sirio, or P2 would make me happy for half the cost.
 
You can get the XTM 21 conversion kit for about $100 at hobbypeople.net

I've had bad experiances with the OS 21 RG, so I can't recommend it.

I can however say that having the extra room on the chassis is welcome. And the ability to use whatever engine I want.

If you get the P2, it is recommended that you get a new header and exhaust, plus upgrade all the cvd's and the rest of the drivtrain. Add it all up and your not to far from doing a full blown conversion anyway.

The XTM kit comes with cvd's and header/muffler as well for a 21.
 
Thanks for the advise!
That gives me a new avenue to explore.
 
It's what I did and I like the truck much better for it. Although, it does take quite a bit of $ to get it to last a weekend without something tearing up on you.

I'd suggest staying with an engine around 2hp. This gives you good power, lower hp/weight ratio which in turn gives you lower temps and longer life out of the engine.

The RRP steel gears in the trans is the main thing I would suggest. They are pricey, but well worth the $. Since I've put them in, I have only had to tear the trans down twice. Once to replace a bearing and once to replace a shaft that was twisted into two pieces. This is in 4 gallons of 21 torture. The gears still looked like new a gallon ago.
 
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