Nitrous on my aftermarket tune....

[fastasleep]

I want to throw a single, wet stage on my mini for import shoot-out in May. My question is this: where should I set my initial timing? Right now I am at 12* initial timing, but I am wondering about where it should be with the nitrous.... I had a single, wet stage on my DSM (75-shot), but never looked at AFR; luckily it held together but I know it was struggling without the proper fuel system. I remember the boost shot off of the chart when the nitrous came on. Now, do I have to compensate for the extra boost (extra, hotter air) + nitrous, or just the nitrous? What fuel pill, nitrous pill, and initial timing should I use?

---------- Post added at 04:35 PM ---------- Previous post was at 04:33 PM ----------

I am not a fan of MSD, but should I buy an MSD BTM to enable the switch that enables my timing when I hit the switch?

[shadow88]

General rule of thumb is 2 degrees retarded for every 50 hp used. That's 2 degrees off your initial 12 or whatever you use.
There's a sticky at the top of the nitrous section to help out with nitrous jets. It's safer to go with a larger fuel jet and work your way down using your wideband as a tuning aid. You'll want to be 1 point richer with nitrous than you would without nitrous.

Again, general rule of thumb is 13:1 N/A
12:1 turbo or supercharged
11:1 turbo and nitrous.

[fastasleep]

good. But will my boost shoot thru the roof and I tune for the result?

[shadow88]

Mine goes up about 3 psi and I just use the fuel jet to compensate. As long as you end up at the correct and safe a/f ratio, what does it matter how it gets there?

[fastasleep]

Mine goes up about 3 psi and I just use the fuel jet to compensate. As long as you end up at the correct and safe a/f ratio, what does it matter how it gets there?

Exactly. I was just looking at doing a 50-shot. Thanks for the advice and direction!

[shadow88]

We want to see results from the shoot-out! Good luck.

[zin]

If the timing isn't optimized, it could he fine where it is, otherwise 2* should be ok for a 50hp hit.

Use 37N/22F as a starting point, it will be rich, but safe. Use the wideband to lean it out to about .5-1 point on the gauge if you feel it's a problem, most of the time a little rich is OK, but not pegged rich gauge.

The boost creep is due to the waste gate not having the capacity to dump enough volume and nitrous, especially a really rich system can add quite a bit, which is why we use it to spool an otherwise too big turbo if the need arises. Outside of an external gate, not much can be done (could port the "puck" area on the turbo but be very careful there, easy to go overboard.

Mike