First off, I am running completely custom timing tables with a non-stock ECM (EBL). Base timing is 4* BTDC and the base timing is correctly set in the bin. I started with stock 350 TBI truck timing and bumped all the cells up for performance till I got knock then backed off. I need to put my base timing back to 0 for my smog check.

My question is once I put base timing to 0, should I go ahead and change the base timing in the bin to zero (for NO net effect on the engine) or should I leave my base timing setting in the bin as is, therefore losing 4* across the board for my smog check? Will my car blow cleaner losing 4* across the board?

 

You would be better off with the 4 degrees less timing. The Cali TBI calibrations run quite a bit less timing is areas. I'll email you an EBL BIN that has the latest Cali auto TBI SA tables in it. You can copy and paste them into your current BIN if you'd like.

RBob.

 

Timing is one of those things where it has to be right in the middle. Too much timing and you have too much of one smog thing, and too little timing and you have too much of another smog thing. I cant remember which of the smog things it affects though. The test checks for hydrocarbons, nitrogen monoxide, and carbon monoxide.

I would just reduce the timing to zero before you smog and see what the results are. Just make sure your EGR valve is clean, as TBI engines relay on the exhaust pressure to open the valve and keep it open.

 

I've always wanted to test my EGR system to make sure it's working properly. I have 1-3/4" shorty headers+full 3" (With a cat) so I worry about exhaust pressure. Any way to verify function of valve and solenoid? How does the EGR system exactly function? Pretty sure it's all L03 stuff on my engine.

 

too much retard and you'll have too high HC's..too little and you'll have too much NOx. Id think 4 degrees retarted would deffinately help the car pass smog across the board better IMO.

 

The only way to test your EGR valve that I know of, is to press the diaphragm up to close it, then stick a finger over the hole. If the diaphragm stays closed, then its ok.

It works by introducing a little bit of exhaust gas back into the combustion chamber. That cools the temperature and reduces emissions.

http://en.wikipedia.org/wiki/Exhaust_gas_recirculation