Hi, I wonder if you can help me please.

I recently fitted a Wet kit from Wizards of Nos but we (myself and Trevor from WON) are seeing a much richer mixture than expected when I start spraying the NOS.

As such, I'm not getting the power expected from the kit.

These are my dyno print outs and AFR's for what should be a 70 shot (With and without NOS)

What we are wondering is, as the intake temperatures drop suddenly when the NOS is fired, could the ECU be adding more fuel and thus making the mixture richer than it needs to be?

My question is to those of you who run Nitrous, did you find similar and if so, what did you do about it?

Thanks

 

Anyone?

 

Your def on the rich side there in the 10's. Try one size smaller fuel jet and you should lean out a bit. Low to mid 11's is safe side for spraying nitrous. It looks like your right about on par with the hp gain you should be seeing. Your baseline was 218 and you wound up with 286. 286-218= 68hp gain. Nitrous shot numbers are very close to the gains you should see. Your fine in my n2o opinion.

 

Thanks for the response.

However I was hoping to understand the reason before I changed the jetting. Studying the graphs and the dip in power between 3k and 4k rpm that seems to coincide with the mixture getting much richer my assumption is that it must be that sensor. The intake temps drop from 40 degrees down to 5 or 6 very quickly (As you would expect spraying very cold gas in).

Is your NOS in a single injector before the throttle body or do you have separate injectors in the inlet runners?

I'm thinking I may go for the 4 injectors in the runners as a next step to see if this help.

 

The dip is probably because your going pig rich when the nitrous come on and it takes a few rpms for the stock ecu to lean out the mixture that's why your power and afr's drop. Honestly if your spraying at 3500rpm that's to soon in my opinion your putting extra un-needed load on the engine. No reason to spray that low change it to 5-5500 rpm it starts coming on. My setup you see in my sig was a direct port setup. If you plan on going over a 75 shot you will be needing it and a after market ecu solution.

 

Ok cool, thanks for your advice.

 

If this is a stock ECU, it will not lean out the mixture under WOT (open loop) conditions, it only uses the O2 sensor during closed loop operation. However, the ECU will add extra fuel as the IAT sensor sees colder air