I am going turbo in about a month, and I have a 98 civic d16y7. will be running about 5.5 to 6 psi. what I want to know, is to tune the car I want to keep the A/F ratio not lean. this i know. do I need to retard the timing or advance the timing. I hear everyone talking about retarding the timing, but to keep it more rich, you would advance it, right?? just a fuzzy topic to me right now! maybe I should quit searching so much and reading so many different threads! LOL


[Modified by turbotec, 10:25 AM 3/1/2002]

 

Ignition timing (timing) and A/F ratio are two completely different things.

To clariffy..... Not only do you NOT want to run lean, you want to run rich. Stoich wont cut it under boost. Richness protects the engine in a number of ways. Fwiw, rich means more fuel than actually needed for a "clean" burn. Stoich (stoichemetric) means a perfect mixture of air and fuel. Lean means there is not enough fuel, and that there is too much air not being ignited. Richness helps for one by cooling off the intake charge (think water injection) and a couple of other technical ways. NOT running rich will lead to you staring at your block on the side of a road one night wondering "where is all this oil coming from" due to the fact a rod broke and put a hole through the side of the block.

Ignition timing must be retarded. This means for instance if your ignition timing is 10* at idle (making up a number here, they varie) then it must be pulled down to around 6-7*. This is going to kill your bottom end power fwiw. It will also hurt your gas mileage. However, it is neccesary to do so to keep cylinder pressures down, and prevent knock, preignition, and unneccesary stress on your rods, rod bearings, and pistons.

Both of these things are a requirement if you are going to boost your engine. You may notice that your car feels alot faster if the ignition timing is raised back to stock. This is true. However expect the life of your engine to dramatically decrease if you run stock ignition timing and pump gas. (NOTE: if you through some 110 oct in the car and wish to, you can raise your ignition timing back to stock to get a good amount more power. Make sure you dont slack when turning it back though.....)

 

wow awesome!! that is what I was looking for. thanks!!

 

 

And to add to his good post, as you increase your revs your ignition advances. So by retarding the timing at idle you are basically taking out timing so when the motor revs it wont advance it too much.

If you go to http://www.hondata.com and look at the ignition maps you can see how it advances the ignition when the motor revs up.

lets say at idle(800rpm) you are at 16deg. and at 4,000rpm your ignition will advance it to about 36deg.
Now, if you retard the timing, to lest say 13deg, then at 4,000rpm your timing will advance it to maybe 32deg.

art