Sirio CL7BSTi vs. RB C6 Vs. OS Speed

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  • Can someone that has run all 3 of these engines compare them please?

    Sirio CL7B STI
    RB C6 BBT7
    OS Speed

    I've been running an RB C6BB T7 on a Mugen truggy, but lately have been curious to try a new .21.

    Power, runtime, torque, power delivery, etc.

    Thanks for the feedback.
  • I've driven all three you mentioned, and all three are great motors.

    Runtime goes to the OS speed.

    Torque goes to the OS speed.

    Raw Power goes to the RB C6BBT or the Sirio.

    Longevity goes to the RB C6BBT.

    For buggy I would run the OS speed at races. For truggy I would run the Sirio or RB C6BBT. You have to be good with the throttle to run the C6 in buggy, or run it fat.

    Here are some other motors you might want to look into:
    http://www.airlandhobbies.com/catalo...1585242210.htm
  • I have owned all three.

    Most Torque by far goes to the Sirio/C6

    Best run time goes to the Sirio

    Longevity goes to OS Speed

    If you are comparing for a buggy, I would personally look at the EVO IV STi over the CL7b STi. The CL7b STi is more a torque motor and does not have the top end that the EVO IV has. I switched from the OS Speed which is a great motor to the EVO IV and I get a lot better fuel mileage out of the Sirio. My speeds were great motor though. I personally like the power band of the EVO IV a little better than the Speed. It has a little more bottom end but still very smooth.
  • i run the speeds, i havent tried the sirio yet, i got one a week ago, just havent had a chance to try it out looks like a good engine, the speed has alot of useable power, if you decide on a speed i sell them on here and ebay for 400, i have run the c6bb and it was a good engine also, none of the choices you have put out would be a bad choice honestly
  • If treated with care (air cleaner) the sirio will outlast anything. my .02
  • I know that the CL7B is a buggy engine, but I feel that it is better suited to a truggy. I am currently running one in truggies at my club, and I am blasting some of the OS 28's away. They have amazing power. I have tried to run one in my buggy, but my vspec pushes the buggy along much better.
  • ive driven c6bbt and speed

    SPEED will get better run time and is little smoother
    SPEED so far is easier to tune.
    AS for the c6bbt it does have good longjevity. but as pit pop says keeping it clean is big key to your motors...

    But if i was to buy it be a SPEED all day long. c6bbt just to over priced now
  • I would look at the new novarossi Plus 21-7FMS..my Plus 21-7BT was faster than my C6 BBT and it's faster than the OS Speed i had also..good fuel mileage also..better than the OS or RB i had..and I doubt that the sirio will last any longer than the novarossi..
  • Quote: I would look at the new novarossi Plus 21-7FMS..my Plus 21-7BT was faster than my C6 BBT and it's faster than the OS Speed i had also..good fuel mileage also..better than the OS or RB i had..and I doubt that the sirio will last any longer than the novarossi..
    Does the Novarossi Plus 21-7FMS have enough bottom end for a truggy?

    Which of thes engines has the most bottom?
  • The original Plus 21-7T had alot of bottom end for a truggy and was completely insane in a buggy. The Plus 21-7FMS is supposedly double that power band.
  • Quote: Does the Novarossi Plus 21-7FMS have enough bottom end for a truggy?

    Which of thes engines has the most bottom?
    +1, doesnt have enough bottom, I've tried it
  • Where u using 1.1 springs and alum clutch shoes? What pipe / manifold where you using? A lot of factors can affect the performance of the engine.
  • Quote: +1, doesnt have enough bottom, I've tried it
    Really..It just came out..A main doesn't even list them yet..I would put my Plus 21-7 up against any .21..I run one in a ST-RR..JP-3 Pipe, stock Kyosho clutch..The OS 28'S have nothing on me in the infield..ballistic down the straights....anyone who has seen my ST-RR run knows this to be true..I always read a lot of trash when it comes to novarossi motors..and it's one of the best motors I have ever had..
  • Quote: Really..It just came out..A main doesn't even list them yet..I would put my Plus 21-7 up against any .21..I run one in a ST-RR..JP-3 Pipe, stock Kyosho clutch..The OS 28'S have nothing on me in the infield..ballistic down the straights....anyone who has seen my ST-RR run knows this to be true..I always read a lot of trash when it comes to novarossi motors..and it's one of the best motors I have ever had..
    I know what you are saying, you start one thread dedicated to STS engines and... and...
  • all things being equal as too the treatment and contamination of the engine, maybe something could last AS LONG as a Sirio, but not longer...

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