Posted by Ben on August 03, 03 at 16:50:33:
In Reply to: Emissions vs performance mods and maintenence - case study posted by Traveler on August 03, 03 at 12:59:23:
Here's mine for comparision with Mexico built, California registered 1996 Vortec 7.4L. No engine/computer modifications. OEM injectors and bi-annual injector cleaner (Berryman's Chemtool B12..double dosage). Now at +142K miles. Just these two years were in my email sent files. Should dig up the previous years and post for the archives.
1996 Suburban 2002 test numbers
GMC/K2500/454 with 127K miles. Passed.
Initially failed with approx HC PPM 480...two new CATs
and dual's later...
Idle (605rpm)
HC PPM: max allowed 150/avg 39/measured 8
CO PPM: max allowed 120/avg 10/measured 0.00
CO2%: measured 15.1
O2%: measured 0.1
2500rpm (2703)
HC PPM: max 150/avg 20/measured 6
CO PPM: max 150/avg 20/measured 0.00
CO2 %: measured 14.8
O2%: measured 0.3
1996 Suburban 2000 test numbers
GMC/K2500/454 with 84K miles. Passed.
Idle (603rpm)
HC PPM: max allowed 0150/avg 0039/measured 0011
CO %: max allowed 1.20/avg 00.10/measured 0.00
CO2: measured 10.9
O2: measured 6.3
2500rpm
HC PPM: max 0150/avg 0020/measured 0002
CO %: max 1.50/avg 00.20/measured 0.00
CO2: measured 11.0
O2: measured 6.1