Upgrading Engines on ZTR

Discussion in 'Lawn Mowing' started by Stratmosphere, Jun 14, 2002.

  1. Stratmosphere

    Stratmosphere LawnSite Member
    Messages: 1

    Having just purchased a brand new SCAG 48" ZTR, I was amazed at the fact that the largest motor was a KAW 21 HP. After watching way to many episodes of "Home Improvement" , I just want more power !!

    The CID on these motors is the same, so how do you mod these engines to spec out to the higher HP ratings ?

    Any insite or help is appreciated, as I am sure there is someone out there that sells high performance parts.
  2. Alan

    Alan Member
    Messages: 1,185

    I can't imagine 21 hp not being adequate for a 48" deck. 25 seems to do fine on a 60" on my Exmark. If the machine is new you would void your engine warranty (at the least) and possibly the warranty on the entire machine. What would you hope to gain by having more power available? You can probably already go faster than the blades can cut without blade speed falling off.
  3. John DiMartino

    John DiMartino LawnSite Silver Member
    Messages: 2,555

    21 on a 48? thats plenty.The Kwi 21 is as strong as the Kohler 23 IMO,so youve got plenty of power.The 23& 25 Kawi are 681 CC's I think the 21 is 640 cc's.
  4. Doc Pete

    Doc Pete LawnSite Gold Member
    Messages: 3,469

    Well, in any event, the 19,21, 23 and 25 are all the same mounting and size, so switching is just a matter of dropping in the new motor. However, 21hp on a 48" deck really should be enough, even running double blades. I'm running a 25hp on my 54" WB with velky and doubles at 7mph and the motor never changes rpm.

Share This Page