Vegas XT/OMC Looper Setup

Randy, I have a question for you regarding the correct setup for my 1989 Vegas XT with an OMC GT200 looper motor on it.  I'm running a DAH worked 27p SRX prop, L&S nose cone with low water pickup, torque tab, and 10" R&R jackplate.  The motor is stock except for 120psi compression, and the propshaft is 1" under the pad.  The previous owner also said that the pad has been "blueprinted".

I've heard that the Vegas XT hull should run mid 80's pretty easy, but the best I've been able to do is 78 on my GPS at 6200 rpms.

What am I doing wrong?  I've tried jacking the engine up higher but it doesn’t run any faster, it just takes more trim to fly the boat.  It seems like the motor just hits a wall at 6200 rpms.

I'm trying to get my hands on a 29p SRX to see if that would help, I've heard that the big 3 liter loopers lose most of there power by 6300rpms.

Anything else you would recommend?

Thanks
Ian Q.

 

Ian,

I'm going to suggest moving the motor closer to the transom. The big OMC just weighs too much. I've set up several with 6 inches and the propshaft at 1 1/2" below. They run low 80's most of the time. Don't worry about gearcase drag without balancing the boat first. The prop should work fine at that position. I would expect to lose top RPM but gain MPH.

Randy

 

 

Please submit whatever questions you have to IHRTechTalk@yahoo.com.  All questions and answers selected will be displayed on this page as they come in.  Note: though all boaters are welcome, priority may be given to I.H.R. members.  Randy can not be held responsible for any advice given.  Though his information and expertise is second to none, he has no control over what you do with your boat.  It is up to you to boat safely and act responsibly, and his advice is only to be used as a guidance for your high performance boat/motor of which you are the one responsible for the risks involved.

Thanks,
Mark C.

 

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