Onroad carb -> Offroad engine...?

[HeartBreak]

Quick question for all the engine gurus out there. What happens if a person runs an offroad style .21 engine with an onroad .21 style carb?

 

[helotaxi]

The carbs are usually the same. The difference is typically found in the sleeve porting. It used to be that only on-road engines had turbo plugs, too.

 

[HeartBreak]

The only reason I ask, is OS has the 20K for their onroad engines, and the 21C for their offroad engines. I was assuming that the 20K had a different fuel delivery pattern than the 21C, because of the massively long needle (it never leaves the spraybar). It looks like it'd give a super-rich low end, lean mid-range, and rich upper-end.

Then again, I could be wrong...?

 

[helotaxi]

If you look on the OS website, they have a retarded number of carbs for .21 engines. Oddly they don't have the 20K listed. Tower does. Looking at the two one of the major differences that I noticed is the 20K doesn't have the provision for different intake venturis. Beyond that, it's really hard to say. The engine should run just fine.