Emissions Test Results - no cats vs MAC

[Scott W]

I thought I would post this for anyone in the future. For several years I have failed my emissions test, and used to get by with a conditional pass. this year I pickup up a used MAC hi-flow H-pipe with cats for ebay for just over $100. It made a huge difference in the results and my car passed with flying colors. I'll post the old and new results so that if your concerned about whether an h-pipe will help you can see for yourself. I couldn't find any actual test results when I was deciding whether or not to purchase a catted pipe.

Here are my actual test results:

40 km/h test
------ limit / no-cats / MAC with cats
hc / 66 / 135 / 25
co / .37 / .65 / 0
no / 757 / 1232 / 404

Curb Idle test

------ limit / no-cats / MAC with cats
hc / 200 / 576 / 15
co / 1 / .87 / 0

As you can see the cats made a huge difference. Absolutely no CO%.

 

[HISSIN50]

Nice thread.

 

[vtecwho]

great info!

I found that with my stock 4cats and a bolt on motor made MORE pollution than with my HCI motor with MAC 2 cat h pipe....same car at different times BTW

I cant wait to see what my blower will do to emissions. Vortech does have a CARB # tho but cali is a bit** to pass now.

they have now made additions to the test.... they now pressurize you gas tank to see if any vapors leak out! many older cars fail.