Anyone desmoged a 77 celica?

[MadProffeser]

Thinking of desmoging my stock 77 celica. I was wondering if anybody has done this and what the pros & cons are for doing the desmog.

I don't want to just go taking out vac hoses. I know I need the vacuum advance but don't know what else needs to stay. Any advice would be great.

[stepho]

To what end?

Most of the anti smog comes from the cams, horribly retarded ignition and catalytic converters (off the top of my head I can't remember which year and which parts of the US got stuck with cats - thankfully we didn't get them until years afterwards here in Australia).
The ignition timing can be fixed tuned around.
The cams would have to be replaced.
Cats you're stuck with.

Most of the vacuum system is to do with cold starting - which is when most pollution occurs.

Will you run foul of any laws?

If you're just after more power then try these methods:
- tune up (fresh plugs and good timing does wonders for old engines)
- better exhaust headers with better mufflers (preferably 2" straight through with relatively stock engine,
- replace carb with Weber 34 carb
- replace the cams and retune
- replace 20R with 22R (even better if you keep the 20R head for raised compression

Disclaimer - here in Australia we never got the 20R but these tricks have had good reports by friends in the US and similar tricks have worked well for my 1977 18R-G Celica (aggressive cams, totally new 2.5" exhaust, Weber sidedraft carbs).

- Stepho

[MadProffeser]

At this point I'm just cleaning up the engine bay. Trying to get rid of all the vacuum lines I can & anything else I don't need. Here in North Carolina with the age of the car it doesn't have to pass emission inspection. It has after market headers, CAT & exhaust, the rest is stock.

[stepho]

Only the vacuum lines between the inlet manifold and the distributor are really necessary (varies timing according to load).
Most of the rest are for emission control while the engine is warming up.

Here's a diagram that a friend found.
http://media.photobucket.com/image/1...Picture014.jpg

- Stepho