PCM Diagnostics & Tuning HP Tuners | Holley | Diablo
Sponsored by:
Sponsored by:

wideband tuning with cats?

Thread Tools
 
Search this Thread
 
Old 05-28-2003, 02:05 PM
  #1  
8 Second Club
Thread Starter
iTrader: (18)
 
eb02z06's Avatar
 
Join Date: Oct 2002
Location: Waterloo, Ontario
Posts: 2,609
Likes: 0
Received 0 Likes on 0 Posts

Default wideband tuning with cats?

How much leaner are the A/F readings on a car if u test with a tailpipe 02 on a car with cats. I was told the readings are about .5 leaner, so if i saw 13.00 on the dyno it's actually 12.5 before the cats. Is it true?
Old 05-28-2003, 08:04 PM
  #2  
TECH Enthusiast
 
WS6 GreeN's Avatar
 
Join Date: Jan 2003
Location: Birmingham, AL
Posts: 582
Likes: 0
Received 0 Likes on 0 Posts

Default Re: wideband tuning with cats?

Can't say for sure since the O2's arent that accurate at WOT, but mine were reporting around .890 at WOT on the dyno and the wideband said my a/f was 13.0 so I feel like the wideband was nearly right on the money. Just my two cents tho.
Old 05-28-2003, 08:17 PM
  #3  
TECH Fanatic
 
red ws6 99's Avatar
 
Join Date: Nov 2001
Location: Las Cruces, NM
Posts: 1,190
Likes: 0
Received 0 Likes on 0 Posts
Default Re: wideband tuning with cats?

The .5 is what most people say a dyno run will be richer by when compared to the street. This assumes the wideband is before the cats. This has to do with the dyno not fully loading the engine. The difference between precat/post cat really depends on the exhaust system, engine setup. Whoever does your turning should have an estimate.

Gary




All times are GMT -5. The time now is 06:36 PM.