Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - Vortec head conversion - EGR
View Single Post
  #10 (permalink)  
Old 03-28-2009, 11:43 PM
curtis73's Avatar
curtis73 curtis73 is offline
Hates: Liver. Loves: Diesel
Last wiki edit: How to find cheap parts
Last journal entry: Found an LQ9 today
Last photo:
Join Date: Dec 2005
Location: Carlisle, PA
Age: 43
Posts: 5,472
Wiki Edits: 16

Thanks: 31
Thanked 52 Times in 44 Posts
Find someone with a sniffer. Some old shops have them for carb tuning. You can really clean up a tune that way.

Additional cam can clean up the NOx that an EGR would normally create, but the increased compression associated with larger cams kinda negates that. Plus larger cam often equals increased HC emissions.

I would personally keep the EGR if you can rig one up, but truly, emissions is largely in the tune. Many of us LT1 guys have gotten away with pretty hefty power numbers and still pass OBD2 emissions in CA. A common setup many of us have done is fully ported stock heads, ported intakes, cams in the 230 duration range, headers, and compression in the 10.5-11 range and with careful tuning it still passes CA emissions testing for 96 vehicles.

I would say focus on the tune first. Down the road if you want to continue cleaning it up then you can add EGR and other smog magic
Reply With Quote