There could be. Everything being set up as equal and perfect as possible, you should be able to get about a minutes extra of run time with a .21 over a .25.
That being said, how often do we ever get "perfect" anything....

For the average joe racer, maybe about 20-30 seconds. Is this a lot.... Could be as much as a lap at the track. Also could be the difference of a 3 stop race and a 4 stop race . it you are running a 30 minute main and can make 7 minutes with a .25 and 8 with a .21, you can make it in 3 stops with the .21. Now this is just a ball park.

Engines today are so over powered as it is, I prefer to be able to control it. Races are won on the track. But they can be lost in the pits.....

Wouldn't the extra power and torque that you have compensate for that though? Let's say I do have to make 4 stops with a .25 is that really a big deal if I'm running 4-5 seconds faster than the guy with .21. Because then Id be able to make up the time I just wasted in the pits within one lap.

more power does not translate to faster, it often translate to being slower..

So all of you think that a .21 would be the better choice then huh? I'm thinking about it a lot and I'm thinking that the .21 is the better choice more and more. How do I get it modded and broken In if that's even possible.

I would go with the .21. The .25 and .28 just don't provide a big enough advantage over the .21's.

For modding services, and this will open up a can of worms, RC Renew and Clock Work Racing Engines. They both will do just about any and all motors out there, can be made to fit your specific needs and provide some of the best customer support in the business. As well as break in services and rebuilds when its time.

http://www.rcrenew.com
or
http://clockworkracingengines.com/

Houston Engine Services is another good one I hear, but have not used them..... yet.

if you are this new to nitro get a stock motor and enjoy racing it first..

I got 2 novas, keep off 21-4 and 21-7xl.
I usually have a buddy of mine break my engines in for me. He's a little busy right now so I was wondering if you guys have info or YouTube or a link to get me going in the right direction on how to properly break in these engines myself. Thanks a mill

Top of the Nitro Off Road threads.....


http://www.rctech.net/forum/offroad-...eak-bible.html

Is there a Virtus 4 port? seen 9 and 7 i think but a 4?

what is the difference between the old PLUS4 and the new BTT .. run time and stability is very important, i suck tuning engines, so i dislike engines which are difficult to deal with . Has cost me too many A-main finals this year because of free but poor engines.

Is the Bonito the fastest Stock .21 Nova produce for off-road? Had a drive of a Team Associated SC8 with a Bonito yesterday and now i want one. Lol!

Guys what would you recommend on a Novarossi P5XLT plug? the place that I raced is tropical weather which is 80-90's & hopefully can make it to the Philippines Big Event next year anyway ... this is gnna be my first time to try the Novarossi Motor which I heard a lot of good things ,I got the motor from the other site which is 3/4 gal. and last thing about the shim? too which I have no idea how many shim do I need ,i will be using the 20% for now ..until the 30% fuel gets here ,please any input /suggestion , thank you..

Hey guys, I was hoping someone could help me. I would like detailed pictures of a novarossi engine that has the rubber seal on the head button. I would like pictures of both the head button and the engine case where the head button is placed.

In short i want to see the thread on both the head button and engine case where the rubber seal is fitted.

would really appreciate if someone could help me out with that

I hope this is what your looking for.