Engine comparison questions.
 

Hi all.

I'm taking my first steps into the big, bad world of nitro buggies, and I was pondering getting one of these three engines:

-O.S. 21RG
-Top/Novarossi T21 BF
-RB Concept CE 3

I don't think I'll be doing any or much racing, and I feel that any of the pricier engines would just be a wasted on me at this point. The OS seems to be well-known as the cheap, decent "throw-away" engine, but how do all three stack-up in terms of things like:

-break-in difficulty
-durability
-sensitivity to tuning

Also, are there any particular (problem) areas with any of these engines, like weak bearings, etc?

Any information that could shed some light on the above would be greatly appreciated.

You have very good engines that you have listed.
If you will not do much racing and even if you did the best engine of the top is the OS rg. Very cheap and a very good engine for the money you cant go wrong.
If you were thinking about moving foreward into racing I would say the BF or the RB Concept. Which are about $100 bucks more then the OS engine.

Good luck

Hi Kyracer.

Any particular reason why you think the OS is better, or is it just a matter of price? The Top and RB engines are maybe $60-$70 more, which isn't really a deal-breaker in my eyes, especially if the quality is better.

I would go with the n21bf. You should get a lot more life out of it then the rg. You will need to get yourself a cheap heat gun to heat it up to around 170 deg. each time before you fire it up. However, it should last you a good 10 gallons if treated properly. The r.g. will probly only be good for around 5 gal.

Wow, that's a pretty significant difference in longevity. I'm definitely not afraid of paying a bit more to get better longevity between rebuilds.

I think at this point, the RB is the only powerplant that remains somewhat elusive: you don't see to many people running them, but those that do swear by them... The higher-end models anyway. I'm guessing that it might be somewhat similar to the 21BF?

if the $60-$70 difference doesn't matter much to you, i would go with the rb first and the top second. i've got a 21bf and like it very much. they take quite a while to break in and you really need to use a heat gun through the first 2 gallons. the only reason i put it second is that the RB i have (an S7II) is the easiest to tune engine i have ever used (i've had a sportwerks also). as for reliability, novarossi and RB are very similar including how many gallons you can expect to get out of them. the one drawback with both of these engines is that they tend to run hot unless you use a larger cooling head (i've got an old S7 head on my 21bf and it dropped temps nearly 30* from 290 - 260). there are plenty of these types of heads available for not very much money.

Hi Adam.

Thanks for the insight. I was quite sure that I'd need a heat gun regardless of which powerplant I went with. Ease of tuning and similar longevity to the Top 21... Hmm, looks like I'll be going RB :nod:

Get the NR21bf. There is probably a reason that nobody runs the RB 3 port. Another good choice at that price point is the Collari B3.

i will just say that i am working on my 21bf right now.... the break in...... and i wish that i got that motor a long time ago..... i wasted a lot of time with cheaper motors.... and that is one thing i will never do again...... the OS RG is a good motor (i also had one of them) but if the extra $70 is no big deal to you... then the 21 BF is a great motor to get...... where I race at there are about 4 or 5 of us that have them in our 1/8 scales...... and we all feel the same way about them.......

interesting point on the RB 3-port. I even checked the RB forums, and can't find mention of it anywhere. Might be worthwhile to ask straight-up; I figure if anyone owns one, they'll be on the RB forums somewhere.

All things said, I've opted to go with Novarossi... A P5X no less. Parts availability seem to be a bit better for these than for RB units.

Question: are there any aftermarket firms that produce green anodized cooling heads for the p5X powerplant? Fiorini makes some really eye-catching heads, but only in blue and black from what I've been able to gather.