I wanted to advance my timing today to see if I got a little more power from my 1990 240sx. Had the TPS off and when I used the light it did not work. I have been using 93 octane for the last 16 years in my s13. I know it calls for regular so I wanted to bump up the timing to make the best out of the higher octane. In the old school of muscle cars we would just advance the timing until pinging would happen and then just bump it down till it stoped. I want to try to advance mine as high as I can before denotation. It looks like the distributor only moves a hair so it must not change the timing a whole lot. I just want to make sure I turn the distributor clockwise and not counter-clockwise to bump up the timing. Is this a good idea or should I just leave it alone and make sure it is set to factory specs. I need to find out what degree I should set it to if I want to leave it at the stock setting.
THANKS
Advancing timing without a light
Re: (AZhitman)
I got a light and it was so high it was way off the scale. I would say if the scale was 2 times the lenght it would be at the end of it. I guess it was at 40 if that is possible. I could not get the idle to go any lower then 800 rpm's so I am not sure if that would make it read high. I also did disconnect the TPS.
What is the highest you would say for max power and the best mileage? I have used 93 octaine for the last 16 years so I do not mind spending the extra money if I can advance it and I get some gain.
I also bought a new computer in 1992 from a company that is out of business that had a very agressive map and they said I had to use high octaine gas. The bad thing is that the stupid computer does not have any lights so I cannot pull any codes. I had to send my factory back for a core credit. It cost $800 in 1992 and did make a bid difference in HP. It said it would raise the stock 140 or 150 I forgot what was stock for 1990 to 170 without any changes. I know the 91 stock HP was 155 and I could take my friends 91 by a 2 car lengths. This is on a stock motor. Now I have a header, 2 1/2" exhaust without a car, air intake. Sorry I am going off the subject.
It looks like the timing was always in this position for years becuse of the marking. I have over 150,000 miles on the original engine and never had any problems and it still runs great but I do have a high idle I am trying to get down. A friend installed the new computer and I do not know if they might have told him to set the timing that high.
So what should I do - set it a little higher then 20 or leave it where it was? I will go for a drive with it at 20 and see how it feels.
If it seems like it lost power what would be the highest I could go with the timing?
THANKS
What is the highest you would say for max power and the best mileage? I have used 93 octaine for the last 16 years so I do not mind spending the extra money if I can advance it and I get some gain.
I also bought a new computer in 1992 from a company that is out of business that had a very agressive map and they said I had to use high octaine gas. The bad thing is that the stupid computer does not have any lights so I cannot pull any codes. I had to send my factory back for a core credit. It cost $800 in 1992 and did make a bid difference in HP. It said it would raise the stock 140 or 150 I forgot what was stock for 1990 to 170 without any changes. I know the 91 stock HP was 155 and I could take my friends 91 by a 2 car lengths. This is on a stock motor. Now I have a header, 2 1/2" exhaust without a car, air intake. Sorry I am going off the subject.
It looks like the timing was always in this position for years becuse of the marking. I have over 150,000 miles on the original engine and never had any problems and it still runs great but I do have a high idle I am trying to get down. A friend installed the new computer and I do not know if they might have told him to set the timing that high.
So what should I do - set it a little higher then 20 or leave it where it was? I will go for a drive with it at 20 and see how it feels.
If it seems like it lost power what would be the highest I could go with the timing?
THANKS