97fourwinns wrote:
That is what I was thinking you were talking about. I couldn't find anything as well on a stock jet size. I think I have a 70 in it now but smell rich fuel. I will check the plugs and size of jet to see what is going on. If a #70 is stock for sea level should I go down one or two sizes for Lake powell and go 3 or 4 sizes to run at 7000'? Thanks
As capt morgan said, it might be different. Depends were your boat was originally sold.
For every 2000ft rule of thumb go down 1 jet. Right now @ 7000ft if you're running RICH that's correct because the stock jetting is too big for 7000ft if it was originally a low altitude boat.
To run at 7000ft, roughly 4 jet sizes smaller then stock (if 70, then run 66)
To run at 3600ft, roughly 2 jet sizes smaller then stock (if 70, then run 68)
That's all guesswork though, the plugs tell the real story. You could always get the fuel injected 4.3 exhaust bits cause they have an o2 sensor (they should fit I think) and purchase a wideband O2 gauge kit
http://www.zeitronix.com/Products/zt2/zt2.shtmlYou could also just run regular automotive fuel with 10% ethanol and not 0% marine fuel. It should allow you to make no jet changes as it's close enough at both altitudes and should run much better for you.