Well im just about done with the build up of my new MBX5 kit. All I have left now are the servos, fuel tank and SELECT a engine. I narrowed it dow to these 3..

1. RB WS7II
2. O.S. VZ-B
3. Sirio BR-PRO

I really cant make up my mind, so i would like to get some comments from u guys on these engines. No matter what it will surely be one of the 3. The O.S. VZ-B was my 1st selection but i hear that the metal the piston is made from makes the engine wear down prematurly. Has anyone else heard this? Or does anyone have one is having no problems with them. My hobby shop said that there is a rumor about it but its not true and people just arent breaking them in right.... Your comments and facts will be appriciated...................

I have also heard the same thing about the O.S. they have been replacing them even though there is no warranty on them. They will probably get the problem corrected if they are shelling out a lot of replacement motors..The Sirio is a little harder to tune. You can't go wrong with a RB motor..I have the Mbx-5 and run a Nova rossi P5 it ROCKS. I have seen them with the REX and a older model O.S. (RZ). they are close to the same.. The P5 has a little more bottom end than the O.S. if you run a tight track you might look into a REX or Rossi P5.

Any reason why your not considering the RB WS7II?? That is what I have in my MBX5 with an OS-2050 pipe and I love the combo. I race on a pretty tight track, not really meant for 8th scales and have plenty of bottom end. When I've gone to bigger tracks, with longer straights, I have plenty of top end as well. I'm on my 8th gallon through the engine and have had zero problems. I'm probably going to get another one to start breaking in to have as a back up. Just a thought.

where can i find the RB WS7II??

Nitro were do you race in FL?

You can buy the ws72 online at www.acehardwarehobbies.com

onroad - i race the state series, so all over.

Offroad - just my local tracks here in orlando, and on occasion in sarasota, ane every once and a while i goto minnreg near u.

wow... that engine is as much as a sportmaxx...

Hahaha, I replied to this while at work, didn't even see that the WS7II was first on the list!! Haha, well, I vote for the WS7II.