[Gmecm] Help me get my LT1 a new sticker

[pmkls1 at yahoo.com]

If you have access to E85 then not only will you get it to pass emissions  
testing but you will also not want to run gas in it ever again. I suggest  
that you run the car as low as possible on gas at home and fill up a five  
gallon container with E85 and then put it in the car once you have it as  
close to empty as possible. For a starter tune, take your normal tune for  
the car and increase the injector constant 30%. You will also want add a few  
degrees of timing advance across the entire table. That will get the car up  
and running and probably pretty well too. Before you begin to alter the fuel  
maps any you will need to run at least a tank of E85 through the car to  
ensure the alcohol content is as close to what is at the pump ( it is  
probably 85% there right now but it does range from 70-85% ). From there  
just watch your fuel trim values and alter the fuel map to suit. If you end  
up wanting to play with the E85 ( which I think you will ) I will give you a  
few pointers. First, you will  need to richen up the AE and PE tables a  
little to avoid hesitation. Second, you will need to mess around with the  
ignition timing, but keep in mind that E85 likes more advance however you  
can easily hurt power by adding too much advance and not know because in  
that engine you will not experience detonation with E85 no matter how much  
advance you add. Also, you will have to add more fuel to your cold starting  
tables avoid extended cranking and bad hesitation in cooler weather ( if it  
gets into the 40's or below). With that info in hand you now know more than  
enough make the car pass emissions and make more power. Please pardon my  
grammar as I sent this from my phone.

Phil

Connected by DROID on Verizon Wireless

-----Original message-----
From: Ron Gregory <ron at gregoryusa.net>
To: gmecm at diy-efi.org
Sent: Wed, Sep 14, 2011 17:32:52 GMT+00:00
Subject: [Gmecm] Help me get my LT1 a new sticker

My son has a '95 Firebird that needs to pass the Texas IM240 dyno testing. 
The vehicle is run on a dyno at 15 mph and 25 mph while sniffing the 
tailpipe.  The car has long-tube headers, no EGR, no air pump, 160-degree 
thermostat, and an empty cat-con.

Last August, I played with the tune a bit, but couldn't get the car to pass 
without installing a new cat-con *and* a special tune. This year, I'd like 
to try [with your help] to pass with an empty cat-con.

The TunerCAT .bin and .txt dump files of the tune that finally worked last 
year are here:

    http://oldpizza.net/formula/2010_08_25_austin_firebird_emissions_5.bin
    http://oldpizza.net/formula/2010_08_25_austin_firebird_emissions_5.txt

I had to mess with the timing, injector constant, and finally the shift 
tables, so it would stay in 1st gear for the 15 mph reading and 2nd for the 
25 mph reading.

The shop is really cool about it. They will actually let us install another 
PCM before we put it on the dyno, so we won't have to actually drive highway  

speeds with this tune.

Any ideas on how to cut emissions down enough to pass "the test"?
Do I have a snowball's chance in August of passing without a cat-con?

I know where I can get some E85.  Would that help?

Ron

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