Alfa Romeo Forums banner

1 - 4 of 4 Posts

·
Premium Member
Joined
·
30 Posts
Discussion Starter #1
502 series motor, 106 series cams, 40DCOE2's w/33 mm venturis, 45F8 idle jets.
Car starts and idles very nicely, pulls very strongly, runs great when cold (Boise ID 3000 ft altitude, 40 degrees F). After it warms up, though, throttle tip-in causes stuttering, particularly around 3000 RPM, and it gets worse as the engine/ambient temperature rise. Still idles great, still pulls strong. The 45s replaced 60F5 jets which were WAY rich after we moved up here from sea-level CA. Feels like accelerator pump not working, or too-lean condition, but it's much better when the engine is dead cold and gets worse hot. ??
 

·
Registered
Joined
·
908 Posts
Your idle jets are probably too lean, try 45F9 or 50 F8, should put you in the right ball park.
Steve
 

·
Premium Member
Joined
·
30 Posts
Discussion Starter #3
Right on the money, GTA R. I had some 50F8 jets, but I'd got it in my mind that since the engine ran well when quite cold, and got worse as it warmed up, it had to be too rich. But the bigger jets sweetened it up just right. Thanks, Steve!

--jim gilmore
 

·
Registered
Joined
·
908 Posts
No problem Jim, a pleasure, Merry Christmas !
Steve
 
1 - 4 of 4 Posts
Top