[DML] Re: Emissions Tuning

["M. P. Olans" <mpolans@xxxxxxxxxxx>]

Mike,
     I have the Island Twin Turbo setup in my car and experienced 
the same thing this year.  Granted, I do have cats as AZ wouldn't 
allow me to register the car without them-long story.  Anyway, you 
can get the Island setup to pass without cats.  My car did in NY 
when Rob Grady had tuned it.  Here's what happened to me this year:

     Everything was high, although HC and NOx just barely failing.  
The car was only four years out of Rob's shop and I couldn't figure 
it out.  I only had 10,000 miles on it since it had left Rob's 
care.  I leaned out the mixture and that brought the HC and NOx down 
to acceptable levels.  CO here is measured in grams/mile.  We are 
allowed 20.  I was testing at over 41.  I was told it was still too 
rich and that there was a lot of unburned fuel in the exhaust.  You 
could hear it crackling when it hit the cats after the car was good 
and hot.  I even tried a can of Berryman's "Guaranteed to pass" 
stuff.  They were nice about giving me my money back....:)
     So I leaned it out some more.  No joy.  CO was now 36.  I 
couldn't get any leaner for fear of the dreaded knock.  I replaced 
the O2 sensor and that brought the HC and NOx down to almost 
nothing.  However, CO was still in the high 30's.  
     So finally I put a timing gun on it.  The timing was dead on, 
but the gun was firing intermittantly.  I thought my gun was bad so 
I tried another gun-same thing.  So I tried the gun on different 
wires.  Turns out #1 and #5 spark plug wires were bad and only 
firing intermittantly.  I figured if I was going to do wires, I'd do 
plugs, cap, and rotor.  All of these looked good except for 1 and 5 
which showed the telltale signs of running really rich.  
     So with everything back together and the mixture returned to 
the original setting, I tested again.  CO was 13.84 grams/mile!  
VICTORY!

So check your plugs and wires.  You might find the problem there.  
And if you want a K&N air filter, let me know.  I recently upgraded 
to one and I am happy with the results.

Matthew
VIN 16816

--- In dmcnews@xxxxxxxxxxxxxxx, "Michael Townsley" 
<michaeltownsley@xxxx> wrote:
> 
> my car has failed the new state auto emissions testing protocol in 
CT.
> 
> The results were as follows:
> 
>  
> 
>               HC(PPM)                CO (%)         NOx (PPM)
> 
>  
> 
> Allowed       172                    0.55               1207
> 
>  
> 
> Emissions     205                    1.52               1548
> 
> Contributing factors could be that I have twin turbos with out 
cats and 
> I have an exhaust manifold leak. I recall some previous discussion 
on 
> the DML about adjusting the car to pass emissions testing without 
a cat 
> (and if fact my car did pass 3 years ago). Can anyone tell me what 
> tuning proceedure I should use to get the lowest possible 
emissions. 
> Thank you.
> 
> Sincerely,
> 
> Mike Townsley






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