High altitiude timing and "Nutter Bypass"

theplasterman · 09-11-2009, 04:12 PM

I just performed the "Nutter Bypass" on my jeep and need to set the timing. While I was reading to see what the stock timing should be there were two readings. One for regular and then one for high altitude. I live in Las Vegas at around 2500 - 3000 Feet. What is considered high altitude, and does it matter for the Nutter?

CJhollic · 09-11-2009, 09:47 PM

I live at 7200 and set mine at 12 bdc. At 2500 I wouldnt touch it. I see you have a weber 32/36. You may want to buy an altitude jet kit and bump your air jet up 3 sizes or your primary idle down 1 size. The webers run a tad rich anyway so the difference between sea level and 2500 and the tendency for webers to run rich might give you a little better performance.

You can test this by your lean best idle mixture. If the screw is out more than 2 turns you may want to consider it.

theplasterman · 09-11-2009, 11:48 PM

This Carb swap has been a real bugger. My idle mixture screw is out 3 turns and my idle screw 3 1/2 turns

carnuck · 09-12-2009, 01:30 AM

Try adjusting the timing advance a little at a time till it pings, then back it down. You may need to adjust it again later after it gets real warmed up.

CJhollic · 09-13-2009, 11:43 AM

Quote:

Originally Posted by theplasterman

This Carb swap has been a real bugger. My idle mixture screw is out 3 turns and my idle screw 3 1/2 turns

Idle speed screw should be about 1.5 in +- 1/2 turn. From that point adjust your idle mixture. here is the link for the adjusting procedure. I would reccomend starting all over on adjustment. At that point you can decide if you need to re-jet

CARBURETOR SET UP AND LEAN BEST IDLE ADJUSTMENT