View Full Version : elevation jetting
08-29-2005, 11:32 PM
I'm thinking it would be a good idea to have some smaller jets on board in case I'm running too rich at tahoe (from sea level). I'v got a 1990 190 with the Holley (fresh rebuild). Is there a formula for # of sizes / 1000' elevation ? Or should I just drop 2-3 #s and try it ?
08-31-2005, 04:53 PM
Drop 2-3 #'s, run it at a specific throttle angle for OVER a minute, cut it off clean, and pull the plugs and read.
Do that at various throttle settings and then make to appropriate changes to adjust for each throttle setting (mains, Power valve, float level, etc.)
You son't be able to adjust the secondaries if you have a 4160 carb so you can try to Band aid that problem w/the flaot level on the secondary side. That's what I did for here. (Park City)
09-05-2005, 09:17 PM
Thanks bro. Been checking plugs that way for years on bikes. Great idea. Motomutt
09-05-2005, 11:07 PM
Anytime! You're right; it's just like on bikes. :)
Probably dropping 3 sizes will be "good enough" for a trip to Tahoe, but if you want to KNOW, then you approch it just like you would w/the bikes. Good luck!