ACCELR8

I adusted my MAFT to obtain 0.89 O2s at WOT using Autotap. Then I found out a friend had access to a wideband A/F meter. We hooked it up to the first O2 port on the passangers side. I adjusted the MAFT to achieve a 13.2 A/F on the wide band. Then I checked my Autotap and the O2s were around 0.93 at WOT. This is how I left the car. A couple months after doing this I read a post, on this site, stating that you should not connect the wideband to an O2 ports because it's inaccurate and you could damage your engine. The post recommended placing a bung in front of one of the Cats. Here are my questions:

1) Which method is more accurate, the 13.2 on the wideband or the 0.89 with Autotap?

2)How do you install a bung infront of a Cat without ruining my headers (stainless steel and ceramic coated)?

Sorry for the lengthy background info, but I thought it was necessary.

Any comments would be appreciated!

Jim

purevilss

I have been banging my head with these same questions. You'd think someone would have some knowledge on this. <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />

red ws6 99

The wideband is accurate, the stock o2s are only used for cruising i.e. 14.7 afr, and are not to be used at WOT (the computer does not use them at WOT). They only accurate at stoich and for regular gas this is 14.7 afr. They (stock o2s) may seem to correlate well with the wideband, but if you change anything you will have to figure out what the new correlation is. Plus stock o2s output varies heavily with temperature (i.e. they are not temperature compensated like the wideband o2s are.

Putting the wideband o2 in the stock pre-cat location is perfectly fine as long as you are only doing it on the dyno. You need the stock o2s for cruising around. The tailpipe sniffer wideband o2 are not accurate. Also you will be slightly leaner on the road than the dyno.

If you want to add a bung for the wide band so you can drive around with it all the time, leave in the stock one in-place and weld a new one in before the cat.

You can get stainless steel o2 bung from jegs or anybody else. Then find you a welder and let him know that its stainless so he can use a different welder rod, etc for stainless.

Hope that helps

Gary

ACCELR8

Gary,

Thanks a lot! Your reply was very informative and helpful. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

Jim