I am looking to get more power out of my 90 w150 by advancing the timing. How much advance would I need to run 89 or 91 octane. Any suggestions will be appreciated!

 

Someone must know about this.

 

you could run 91 octane as is but if you want a bit more power you can advance it a degree or 2 at a time till you get it to where you want it.

 

Stock is normally 10 degrees and I am running at 18. I there any problem with that?

 

18 doesn't sound right. as long as your truck seems to run good that is all that matters.

 

Higher octane fuel is a waste of money in a properly tuned stock engine. This is especially true with a computer controlled engine. If you have to deviate from specified factory timing something else is wrong.

 

When I ran 91 octane on 18 degrees advance, there was a noticeable difference but not huge. When I pull the car hauler, it helps alot. Also, I am running 4.88 gears with 35s and getting about 16 mpg on the highway pulling the trailer. I have done some other mods to help improve the gas mileage so I know a little about mechanic work. I built a drag car from the bottom up an we advance the timing to 36 degrees on 100 octane. I just wanted to know if anyone knew the exact or close specs for these dodges.

 

I assume you are talking about total mechanical advance on the 36 degrees.
A stack 318 will do good on 34 or 35 total with no vacuum.
With vacuum you can get 52 or 53 degrees at part throttle and it should be good. When the throttle is wide open it goes back to mechanical advance only.
To add initial timing you need to limit the centrifugal to 34 or 35 total to keep away from detonation.

 

I assume you are talking about total mechanical advance on the 36 degrees.
A stock 318 will do good on 34 or 35 total with no vacuum.
With vacuum you can get 52 or 53 degrees at part throttle and it should be good. When the throttle is wide open it goes back to mechanical advance only.
To add initial timing you need to limit the centrifugal to 34 or 35 total to keep away from detonation.