Calif Emissions
Thread Starter
Le Mans Master
Joined: Oct 2006
Posts: 8,941
Likes: 35
From: El Cajon California
Calif Emissions
With a 1978 L-82, automatic I would like to get some more power, stay legal and not spend alot of money.
Assuming the motor is in basically good shape.
I was considering swapping out the cam for a bigger one
recurve the distributor, checking the play per tech article
Replacing the pathetic cats with high flow versions.
Adjusting the Q-Jet
What other small things can be done, where I can pass emissions test and pep up the old C-3.
Assuming the motor is in basically good shape.
I was considering swapping out the cam for a bigger one
recurve the distributor, checking the play per tech article
Replacing the pathetic cats with high flow versions.
Adjusting the Q-Jet
What other small things can be done, where I can pass emissions test and pep up the old C-3.
Racer
Joined: Jul 2004
Posts: 400
Likes: 1
From: California
right now im going .030" over and bumping compression up just a hair, getting flat top pistons and different manifold. going to keep the stock Q-jet until i pass smog, then Hello Edelbrock 
plus im gonna try to do a custom duel exhuast setup so when smog rolls around 2 yrs from now i can unbolt a couple things and be back to the original 2-1-2 exhuast. other people will have many more suggestions and opinions.
plus im gonna try to do a custom duel exhuast setup so when smog rolls around 2 yrs from now i can unbolt a couple things and be back to the original 2-1-2 exhuast. other people will have many more suggestions and opinions.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
I feel ya, I have similiar desires.
I wonder about the low compression ratios.
Why would GM lower them?
Was it gas driven by allowing low octane, ethonol?
Better fuel economy?
Compression by itself doesn't mean dirty exhaust.
My motor is stil tight and clean running, when it gets
time to rebuild I am thinking stroking to 383.
I am scared to to anything for fear of not passing.
I read there are good cams avail from Comp that will
not harm smog.
I am in Cal and have to keep all the emissions equip,
run stock idle speed, stock base timing.
Changing parts effects these settings.
I have read about people taking smog dev off and doing
grate improvements. I haven't read about anyone doing
good mods and keep smog equip and pass.
So I can't help from personnel experience.
Sorry
I wonder about the low compression ratios.
Why would GM lower them?
Was it gas driven by allowing low octane, ethonol?
Better fuel economy?
Compression by itself doesn't mean dirty exhaust.
My motor is stil tight and clean running, when it gets
time to rebuild I am thinking stroking to 383.
I am scared to to anything for fear of not passing.
I read there are good cams avail from Comp that will
not harm smog.
I am in Cal and have to keep all the emissions equip,
run stock idle speed, stock base timing.
Changing parts effects these settings.
I have read about people taking smog dev off and doing
grate improvements. I haven't read about anyone doing
good mods and keep smog equip and pass.
So I can't help from personnel experience.
Sorry
Just another Corvette guy
Joined: Feb 1999
Posts: 8,518
Likes: 3,865
From: Palm Springs, CA.
Why don't you just change the rearend gears?
A lot less money and "instant fast".
I lowered the gears in a stock '79 L-48 car and installed a Transgo Stage II shift kit. The car would absolutely burn the tires off from a standing start, give a big tire chirp and jump a little sideways when it hit second gear under full throttle and it would still pass California smog.
Pretty cool for a 195 net horsepower car.
Best,
Greg
A lot less money and "instant fast".
I lowered the gears in a stock '79 L-48 car and installed a Transgo Stage II shift kit. The car would absolutely burn the tires off from a standing start, give a big tire chirp and jump a little sideways when it hit second gear under full throttle and it would still pass California smog.
Pretty cool for a 195 net horsepower car.
Best,
Greg
Drifting
Joined: Feb 2005
Posts: 1,738
Likes: 2
From: San diego ca
With a 1978 L-82, automatic I would like to get some more power, stay legal and not spend alot of money.
Assuming the motor is in basically good shape.
I was considering swapping out the cam for a bigger one
recurve the distributor, checking the play per tech article
Replacing the pathetic cats with high flow versions.
Adjusting the Q-Jet
What other small things can be done, where I can pass emissions test and pep up the old C-3.
Assuming the motor is in basically good shape.
I was considering swapping out the cam for a bigger one
recurve the distributor, checking the play per tech article
Replacing the pathetic cats with high flow versions.
Adjusting the Q-Jet
What other small things can be done, where I can pass emissions test and pep up the old C-3.
- Full length headers.. Hedman 68281...this keeps AIR system - no EO number but I've yet to have any smog station give a wet slap.
- 2 1/2" - 3" hi-flow cat - 2 1/2" muffler of choice. 3" pipe has greater cross sectional area than dual 2" (not that dual 2" is in the least bit desirable
) - L82 manifold is ok...Edelbrock is maybe slightly better (make sure to get one with EGR valve)
- Heads - Edelbrock aluminum or frankly your choice of any heads with heat crossover...get small combustion chamber to up CR
- Cam - you can go up a little bit with the cam.. more than a little bit if you have an L-48..not a ton if you have a L-82. Go Hyd Roller if you can afford it - otherwise hyd. Flat tappet.
- Gearing...if you have an L82 with an auto you should have 3.55 gears...upping that to the 3.70's that were std with a stick will help buyt you might get more seat of the pant improvement with a 700r4 with its lower 1st gear and overdrive final gear.
Burning Brakes
Joined: Aug 2006
Posts: 1,155
Likes: 0
From: San Diego California
With a 1978 L-82, automatic I would like to get some more power, stay legal and not spend alot of money.
Assuming the motor is in basically good shape.
I was considering swapping out the cam for a bigger one
recurve the distributor, checking the play per tech article
Replacing the pathetic cats with high flow versions.
Adjusting the Q-Jet
What other small things can be done, where I can pass emissions test and pep up the old C-3.
Assuming the motor is in basically good shape.
I was considering swapping out the cam for a bigger one
recurve the distributor, checking the play per tech article
Replacing the pathetic cats with high flow versions.
Adjusting the Q-Jet
What other small things can be done, where I can pass emissions test and pep up the old C-3.
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Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Keep the Q-jet. The Edelbrock will not be better. If it is, your Q-Jet simply needed work.