Thread: O2 # & idle ?
View Single Post
Old 06-19-2018, 07:00 PM   #2
Ed Wright
Veteran Member
 
Ed Wright's Avatar
 
Join Date: Mar 2005
Location: Sand Springs, OK
Posts: 8,132
Likes: 896
Liked 389 Times in 168 Posts
Default Re: O2 # & idle ?

Quote:
Originally Posted by rod View Post
I understand most everyones O2 #s will be somewhat different due to all the variations. however there must be a # + or - where your engine will achieve best idle.
FYI, I use a Holley 600 on my 327 Chevy. not a real legal 350 hp, but close. Vegas is closed for the summer, so I am trying to get several things right.
Rod in AZ
An O2 sensor, located in the collector of a race car, normally indicates very Lean at idle idle. The added overlap of a race cam, causes the exhaust to "pulse" in & out of the collector. Pulses pulling clean air, containing oxygen will give bogus Lean numbers. I bought a 24" slip joint with a 45 Bend in it for setting my idle air/fuel ratio in the car. On an engine dyno that should not be an issue, with the exhaust system they use. Only with open headers. Should be no issue in a vehicle with full exhaust. I hope the Lean reading is what you were referring to. The open collectors are the reason you normally would not idle one in Closed Loop.
__________________
Ed Wright 4156 SS/JA
Ed Wright is offline   Reply With Quote