Yamaha Genesis 80FI Timing

[dalspaugh]

Hey Everyone, new to the site and the competition. I'm starting some calculations on the Intake manifold for our car.

I can't seem to find the timing for this engine (gensis 80FI - out of a phazer snowmobile) though. I've even called yamaha who seems dumbfounded by the question. Last year's team supposedly measured the cam valve open to be 288 degrees. Can anyone confirm this?

But really I need all the timing measurements. I was planning on taking the valve cover gasket off and measuring soon, but figured someone on here might be able to help out.

Thanks!

[Mbirt]

Here's a link I found to the service manual: http://yamahaservice.forum24.s...aservice-post-3.html (http://yamahaservice.forum24.se/yamahaservice-post-3.html)

I didn't see any duration numbers, but I'm sure you'll find something useful in it.

This is no replacement for measuring the profile yourself, but you could probably make an inference regarding cam timing by comparing the numbers from the YZ250f, the R1, and the Apex snowmobile of the same vintage as your Phazer motor.

UM-Dearborn published the results of a Genesis 80fi intake manifold design in 2010 IIRC, but I can't find the document.

[kevfort]

Last year we measure it, i will ask the engine guy for the data.

If i can't find it, you can measure it very easily but openning the cam cover which have a rubber gasket(reusable) and the flywheel cover wich you will have to replace the gasket. Just search on the net for a degree wheel and print it. Paste this one on a rigid carton and fix it on the flywheel bolt.

If you have a dial gauge, put it on a valve and turn the crank until it open of 0.020" or around. Make a complete cycle (full open to almost close) and stop when you return to your starting measure...here its 0.020".

Good luck