Smog stuff removal

[Stinky]

And, racer's don't care about anything but WOT....that is why they don't care about vacuum advance.

 

[Green Monster]

You want/need vaccuum advance @ part throttle.

Here is the Reader's Digest explanation. For max power & economy, your motor wants as much advance as it can tolerate.

The VA gives you advance at part throttle. At WOT it doesn't do anything and the distributer springs and weights control the advance.

As you back off on the gas....load goes down and vacuum goes up. Because there is less load and gas, your motor will run better w/more advance.

SOOOOO...for example, when you are pushing down on the pedal about 1/4" (high vacuum, no load & no gas), it will run better w.a bunch more advance. Or under the same deal, w.o VA, you can push down on the throttle more, for the same amount of power.

Thanks....yeah I plan on timing it again. He moved it from 8 to 3, and I've heard I can go as high at 12. So I think I'll start at 8 and go up from there. Only thing is I have to figure out my timing light. Someone gave it to me and so I have to figure out what all the switches and buttons do. I don't remember them being this complicated! BTW, I understand I have to disconnect the vacuum advance, and plug the vacuum line to set timing, correct?

 

[dyeager535]

Theoretically on a Quadrajet if advance is hooked up to ported vacuum you don't really have to worry about that...with the throttle at idle, the vac advance slot won't be uncovered. But it's good practice to do so.

Unplug your vac advance at idle... and see if there is vacuum on the line and/or your idle changes. Realistically best overall performance is going to come with the vac advance hooked to manifold vacuum, which won't pass emissions. But it will allow you to run more advance at idle, which makes idle much more smooth. You can crank the distributor up to ~20* when you are adjusting and see for yourself. You just can't leave it that way.

 

[K85 Octane]

Dude, that was far too easy a fix to pass smog. Don't even consider taking all the stuff off if passing is that easy, it's not worth it. The stuff doesn't have to work, it just has to be in position and look like it works. Nothing of mine works and passes fine.

 

[waybad1]

I used to take everything off related to the emissions system after every smog test. It was
a pain but ran so much better with an open air filter, no smog pump and timing advanced. Funny
thing is my friend ran the test once with everything off and it still passed the tailpipe test.

 

[Green Monster]

Yeah the only pain was that preheater tube that I had to mock up. Thankfully I don't have factory cats or EGR, and the smog pump isn't much of a drain on it. So I'll leave everything on and just time it. Thanks for the heads up on the timing. Next time I have to smog it, I'll just set it back to 3 deg.

 

[diesel4me]

I had to make up a similar heat stove tube like yours for the 307 I put in my van,I had all the stock air cleaner plumbing but no sheet metal around the exhaust manifold..
What I did was get a 18" piece of that metal flex pipe they sell for temporary exhaust repair ,that fit the air cleaner inlet ,and I just smooshed the other end some and hose clamped it to the exhaust manifold..I put the "foil" pipe over that to help insulate it,so the fan wont just blow cold air on it during warm up..

I did not need it to pass emission,the engine just loved to stall or have the carb ice up in the fall and winter ,on cool damp days,until it was driven a good 10 miles..with the pre-heater stove working it would usually run good after just a few minutes of idling..

I had a 305 in a '79 C-10 that was cold blooded too,had to set that up the same way,only I used a section of metal stud pop riveted together to make a box tube that I clamped to the exhaust manifold..the stud had a hole the right size for the flexible foil tubing to the air cleaner.

I had to rig up the vacuum hose on the heat riser EFE valve to keep it closed all winter,or the truck would stall,ice up the carb,and the throttle would stick open at times from icing..I tried a 195 thermostat,didn't change anything but it did give better heat..I think the Edelbrock carb and 1" spacer under it just kept the carb too cold in winter and it needed all the hot air coming in it could get ,not to ice up..

 

[Green Monster]

I had to make up a similar heat stove tube like yours for the 307 I put in my van,I had all the stock air cleaner plumbing but no sheet metal around the exhaust manifold..
What I did was get a 18" piece of that metal flex pipe they sell for temporary exhaust repair ,that fit the air cleaner inlet ,and I just smooshed the other end some and hose clamped it to the exhaust manifold..I put the "foil" pipe over that to help insulate it,so the fan wont just blow cold air on it during warm up..

I did not need it to pass emission,the engine just loved to stall or have the carb ice up in the fall and winter ,on cool damp days,until it was driven a good 10 miles..with the pre-heater stove working it would usually run good after just a few minutes of idling..

I had a 305 in a '79 C-10 that was cold blooded too,had to set that up the same way,only I used a section of metal stud pop riveted together to make a box tube that I clamped to the exhaust manifold..the stud had a hole the right size for the flexible foil tubing to the air cleaner.

I had to rig up the vacuum hose on the heat riser EFE valve to keep it closed all winter,or the truck would stall,ice up the carb,and the throttle would stick open at times from icing..I tried a 195 thermostat,didn't change anything but it did give better heat..I think the Edelbrock carb and 1" spacer under it just kept the carb too cold in winter and it needed all the hot air coming in it could get ,not to ice up..

Yep, that's pretty much how I did mine. Cut the end and flayed it open so it would wrap around the manifold, and used a couple of hose clamps. Can't tell if it works, as it doesn't get cold here, but the smog guy said it was fine.