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o.s .21 rg-x motor?

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T

timmytimmy14

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will the o.s .21 rg-x motor fit in the savage .25? if it doesn't what stuff do i have to buy to make it work.
 
Anything will fit in a savage.Except like a .18 and smaller. Just drop it in...
 
Actually, the 21 RG needs a header adapter and a different header gasket to seal properly. At least mine does.

Here's the adapter: http://www.neweramodels.com/cgi-bin/item.cgi?part_id=211

It's not a bad engine. I'm running one as my winter engine. It has about 7 gallons of use and I'm running 15/52 gearing and it will pull wheelies in grass pretty easy.
 
does that .21 put out that much more than the .25?? A lot of the motors need a little something to get them rolling in a vehicle. Most engines just bolt right in but some need a little something
 
I don't know. I've never had a HPI 21 or larger engine. The only HPI engine I had was a 15FE and I just traded that for a savage pipe.

I normally run an Omega 21 Comp. Supposedly puts out 2.5hp. I know it cranks out more than the OS ever did... but the OS is so damn reliable, it's hard to beat.

To get the Omega working well, I modified a carb off of a dead 21 RG that I had. Now it really screams and is a lot more dependable. But it's a discontinued engine.
 
You might as well save a few more pennies and pick up an XTM (it will run circles around the rg)

Why you may ask? The rg is aimed more towards buggies, Its more upper end power, but what you need is TQ.
 
1 Bad STi said:
You might as well save a few more pennies and pick up an XTM (it will run circles around the rg)

Why you may ask? The rg is aimed more towards buggies, Its more upper end power, but what you need is TQ.
Click to expand...

He's not lieing here. His XTM definitly gives my Omega a run for it's money. My omega is also a buggy engine. It has a smaller head than most typical 21's I've seen made for MT's. Most of the Omega's power is in the middle of the range.

Here's a link to an XTM 24.7: http://www.hobbypeople.net/gallery/146027.asp
 
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is the xtm one a direct drop in or do i need a header adaptor thing. if i need it can you show me which one. a direct drop in motor would be so much better though
 
The XTM should drop right in with minimal effort. No header adapter is needed. It's a rear exhaust round external extruded port just like the HPI 21, 25 and I think 28.

One suggestion though, make sure to do the 4-spider diff mod if you haven't already. That XTM has a lot of torque and has a tendency to chew diffs up.
 
If not had one problem w/ my 2 spider diffs. I've ran 3 gallons through my XTM as well and had my share of bad crashes. Although mine are full of 5k and 3k DIFF oil.

However, the 4 spider is a great upgrade, espeically since HPI has made it a user friendly Upgrade and now sell the full kit w/ the stronger spider gears.
 
The XTM will fit right in no problem, it also accepts roto start if you want.

olds, that avatar is awesome! :)
 
Yea, i do run taller gearing. Still pulls the wheels up like crazy though.

Remember if you run the roto w/ XTM, she has more compression so your going to want to loosen the glow plug upon starting each time. otherwise your going to roast one-ways
 

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