06-07-2011, 09:46 PM #1
- Join Date
- Aug 2006
- Orange County, Ca
Filling Cross Port on carb Manifold
On the GP1200R Manifold, Is there any advantage on fill in the cross port ???
06-08-2011, 08:42 AM #2
This is a quote from a Group K technical article.
Inlet Signal Part 2 - Many 2-cycle pwc engines (Yamaha 1200s included) employ the use of intake manifold cross-over channels to improve the smooth-ness of low speed carburetion. These cross-overs work very effectively for stock engine platforms. However on a setup built for high rpm output, these cross-overs can significantly reduce inlet signal at high rpm. This reduction in high rpm signal is not a problem for stock engines, however it can cause uneven “full throttle” fuel metering on a high rpm modified platform. In testing we’ve done on other modified pwcs, we have found that simply blocking off these inlet manifold cross-over channels can yield a big improvement in the accuracy of fuel metering during extended full throttle passes.
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
By scittb in forum Yamaha ClassifiedsReplies: 49Last Post: 05-11-2010, 06:27 PM
By Seanace1 in forum Polaris How To & FAQsReplies: 10Last Post: 07-04-2009, 09:21 AM
By WFO in forum Yamaha ClassifiedsReplies: 6Last Post: 05-09-2009, 10:48 PM
By mrjetskey in forum Sea Doo ClassifiedsReplies: 0Last Post: 05-26-2008, 11:08 AM
By wetherby in forum Polaris PWC PerformanceReplies: 4Last Post: 01-06-2007, 12:28 PM