How Much To Lower Timing With 75 Shot

Discussion in 'Fox 5.0 Mustang Tech' started by Silver5.0Stang1990, Jul 23, 2013.

  1. How much do I need to lower my timing when I use a 75 shot.. Right now it's set to 14 degrees but I'm going to change my plugs from 25s to 24s and I'll gap them around 38.
  2. I would set your base timing around 8 for that. The colder plugs will help too!
  3. Thanks I actually set it around 9 at first then moved it up to around 11.. I also raised my fuel pressure from 40 to 50 just to make sure it doesn't lean out.. It ran really good dropped my ETs from 13.80s to 13.20s.
  4. Next week I'm putting in the 125 jets and hoping everything holds!
  5. What nitrous kit are you using? If you're using the NOS kit or something that operate similarly, then you don't need to mess with fuel pressure at all.
  6. I'm using a slightly older compucar nitrous kit.. It wasn't running real rich even after raising the fuel pressure so I don't know.
  7. I run my timing @10 deg with a 125 shot and 93 oct fuel
  8. Instructions for my ZEX kit states that with a 75-shot, the stock timing is sufficient. It drops 2-degree's at 100hp. The instructions are generally a little on the conservative side for wide safety margin, so if you're running 8-degree's now, you should be more than fine. As always though, make sure you're also running good fuel.