Dry shot Nitrous question.

[sbiggi]

So I was thinking of running some no2. It would be a dry 55 shot from a zex kit.

I have 950cc injectors and they only run at 60-65% dutycycle right now.

I was thinking of setting up my chip to activate the purge solenoid at 100% throttle and between 5000 and 7300 rpm in order to activate the no2.

and to get more fuel use the aux function on the maft to increase the airflow signal.


I do have a wideband and knock gauge.

Does this sound safe enough to run?
This would be on top of 30 psi of 50trim and more timing and 110 octane.
I can easily back the timing off a couple of degrees if needed.

-Seth

[intaginize]

I personally would not run a dry shot, it's just too risky to do when you can run a wet shot or a direct port setup with fuel going in at the same time. If you still want to do it you'll need to run at least 108 Leaded gas and you'll need to retard the timing around 2 degrees. I'm going to be running a ZEX direct port kit, I haven't decided yet if I'm going to run it this weekand. I have all the parts I need to install it but I don't really have time to get the bottle filled and the car tuned before Saturday Morning unless I call in sick to work on Friday. :)

[KeltonDSMer]

What is your objection to a wet setup? I just don't see the advantage of adding a bunch of extra electronics as opposed to a t-fitting pre rail and running a fogger on the TB elbow or whatever. Get your jets right and no more tuning.

[v413nc3]

*If* you can add extra fuel through your injectors there isn't a need for a wet kit. I wouldn't add timing though. The added octane level should help too.

[Hal]

With N2o, the pump and other fuel system parts need to be able to supply enough fuel to both the rail and the nitrous system.

The higher the boost, the harder this is to do.

With a wet shot, fuel delivery is done via the fuel jet.

With a dry shot it uses the vehicle injectors and elevated fuel rail pressure.

Now your fuel pump will get an even greater workout because it actually has to deliver fuel at a higher pressure rather than at a lower pressure with a wet kit.

Also, your injectors have to have enough capacity to flow the total fuel needed.

[sweck]

Nothing wrong with a dry kit as long as you use some common sense. As long as you can get the extra fuel when you need it you shouldnt have an issue. Also for a true 50 shot you shouldnt need very much fuel anyway- on an EVO we simply opened the valve of a bottle in front of the intake and the car gained 30+ whp with no change in AFR. Even so,my guess is you are going to have issues getting the fuel right, so start fat and work thin, going lean on nitrous is not a good thing.Also realize that 50 shot jets typically yeild 80+whp on turbocharged cars, and tune accordingly.


Dammit sweck-logout! This is fusionsport on swecks login since he cant remeber to logout.

[KeltonDSMer]

I thought dry kits like ZEX supplied fuel via an increased pulse width and not by elevated fuel pressure.

[Hal]

From a Zex item on the ProStreetOnline site:

"Dry nitrous oxide systems provide fuel enrichment by increasing the fuel pressure to the fuel injectors as the nitrous system activates."

[sbiggi]

I figuer if I run my race tune and the 55 shot, that will probably be way to much power for the stock engine.

I think if i run 25 psi and retard my race chip a couple degrees I'll be ok.
The injectors have plenty of capacity left and the pump might be on edge, but running less boost should help keep me safe fuel delivery wise.

The reason I would be running a dry shot is it would be free and way easy to install.
All I need to do is run the nitrous line and a couple wires to get it to run the way I want.

Hopefully my stock enigne will stay in one piece with a little over 400 whp. :cool:


It should be safe, as I wrote some code that will only let the nitrous on between 5000-7300 rpm, 95%+ throttle, and above 60 mph.

[v413nc3]

What fuel pump are you using? If it is just a W255HP I would suggest you upgrade it just in case.

[intaginize]

Or install one of these instead of upgrading the pump, anyone use one of these before?? Do you just tap it into the fuel Line before the filter?

http://cgi.ebay.com/ebaymotors/ZEX-BOOSTER-FUEL-PUMP-KIT-PART-82020-Up-to-650-HP_W0QQcmdZViewItemQQcategoryZ33740QQitemZ80697755 52QQrdZ1QQsspagenameZWD1V

[v413nc3]

That looks to be just an inline pump. It would be best to tap it in earlier than later, (read closer to the tank than the rail). That's one way to get more flow at the higher pressures.

[sbiggi]

What fuel pump are you using? If it is just a W255HP I would suggest you upgrade it just in case.

yeah just a 255. I'll watch the Wideband and make sure its not leaning out.

[sbiggi]

So, yeah.. picked up this kit from my friend.

I cant believe they charge so much for these kits, there is absolutley nothing to them. A basic kit has no more then $300 worth of stuff that one could piece to gether them selves.

Anyways, I think I'll be testing this thing out tonight.