Date:         Fri, 26 Jul 1996 16:42:49 -0400
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         SyncroHead@aol.com
Subject:      Re: vanagon headers

In a message dated 96-07-26 14:28:13 EDT, natasha!kombi@adobe.mv.us.adobe.com
writes:

>> but dual exhausts would seem the way
>> to go to reduce backpressure.  Just a thought.

>Yeah, but it would play hell with the FI, which counts on a single O2
>sensor. 

Yeah, but you could just use a single O2 sensor and make the "assumption"
that the other 2 cylinders are operating about the same.  On the VW FI system
the fuel injectors are not individually controlled, so the only time that one
pair would be different than the other is when there's a problem with one of
the cylinders.  Having one O2 for the collection of 4 exhausts would not be
much help in this circummstance either.

I think the stopper might lie in combining cylinders from each side of the
engine. 
In Verbeek's words:

># 2 and 1 follow eachother in the firing order as are # 4 and 3,
>combining 1 and 3 & 2 and 4 is better because the pulses are better
distributed
>over the total VW flat four cylinder cycle, farther apart, i hope i'm using
the
>right words here btw.

Regards,
Jim Davis
87 GL Syncro
88 GL Wolfsburg