84 smog legal replacement heads
06-26-2007, 08:47 AM
#1
Corvette Enthusiast
Thread Starter
84 smog legal replacement heads
Hi all,
I am thinking about getting a set of better flowing heads (eventually) to replace the stock heads to allow the Vette to breath a little better, but was wondering about the emissions. First I was thinking about a set of GM Vortec heads (re-drilled for the standard manifold) but then I figured I'd look into some Dart or Trick Flow heads etc. However, the California emissions board really takes this whole "keep it stock" thing serious. I was wondering if anyone knew how far I could go before I wouldn't pass smog any more.
I am thinking about getting a set of better flowing heads (eventually) to replace the stock heads to allow the Vette to breath a little better, but was wondering about the emissions. First I was thinking about a set of GM Vortec heads (re-drilled for the standard manifold) but then I figured I'd look into some Dart or Trick Flow heads etc. However, the California emissions board really takes this whole "keep it stock" thing serious. I was wondering if anyone knew how far I could go before I wouldn't pass smog any more.
06-26-2007, 09:00 AM
#2
Race Director
The problem isn't so much in the heads as in the intake. Very small and restrictive. It's known as "critical path". You will only flow as much as your tightest restriction. Kinda like a 36 or 48 oz drink, you only flow as much as the straw will let you.
06-26-2007, 09:24 AM
#3
Corvette Enthusiast
Thread Starter
I've heard that the crossfire intake is a big restriction so I have a ported one that I'm going to use. It won't flow as much as an X-Ram, but will work fine up to 5000rpm's, which is as high as I'm going to go. My concern was the heads. I've heard that they are the worst flowing heads that GM put on a Vette. (sigh)
06-26-2007, 12:07 PM
#4
Melting Slicks
www.aeroheadracing.com
dart iron eagle heads are a nice flowing head. Only $625 for the pair. Read up on them they are nice.
dart iron eagle heads are a nice flowing head. Only $625 for the pair. Read up on them they are nice.
06-27-2007, 11:12 AM
#5
Le Mans Master
Member Since: Jul 2001
Location: Silicon Valley Kalifornia
Posts: 6,252
Likes: 0
Received 1 Like
on
1 Post
I am very happy with my AFR heads. Start by improving the heads...then there are alot of guys here that have improved the flow numbers on their '84 setups and can help you. Do a search also. Click on "archives" too for the search.
06-27-2007, 04:38 PM
#7
Racer
For California as long as the aftermarket part is CARB certified your cool. The part will come with a CARB label on it usually. Doing a 383 in cali myself, so much research is needed to keep it smog clean.
06-27-2007, 11:18 PM
#8
Team Owner
Member Since: May 2002
Location: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Posts: 24,337
Likes: 0
Received 17 Likes
on
16 Posts
The cylinder head doesn't need a CARB number. Just paint it black if you want to hide it.
It WILL need an internal EGR passage though. Many heads don't have this, it's directly in the middle of the head. Edelbrock has a few smog legal (EGR) heads.
It WILL need an internal EGR passage though. Many heads don't have this, it's directly in the middle of the head. Edelbrock has a few smog legal (EGR) heads.
