needin some nitrous tunning help

[layinframe]

needing some nitrous/fuel tuning help


first off I have a nos super power shot plate system
73/82 jets
fuel cell just for nitrous running 91 oct my system call for 5-6 psi on fuel side but I have a 14 psi pump on it. y I have a 14psi pump fig higher fp more fuel atomization please correct me if im wrong


what my question is had 73/82 jets on 89 octane ran good checked plugs looked rich fig higher fuel pressure id drop fuel jet to 63 checked plugs a little lean so I went to a 71 got 91 octane fuel ran it and had no where near the power it did on 89 octane and the fuel jet that was a little lean. trying to fig out what happen here any help would be great

[stumpy]

Originally Posted by layinframe

needing some nitrous/fuel tuning help


first off I have a nos super power shot plate system
73/82 jets
fuel cell just for nitrous running 91 oct my system call for 5-6 psi on fuel side but I have a 14 psi pump on it. y I have a 14psi pump fig higher fp more fuel atomization please correct me if im wrong

The kit is calibrated for specific pressures, both n2o and fuel, and timing. Did you ever run it at 5-6? Too much fuel can be a very bad thing.

Originally Posted by layinframe

what my question is had 73/82 jets on 89 octane ran good checked plugs looked rich fig higher fuel pressure id drop fuel jet to 63 checked plugs a little lean so I went to a 71 got 91 octane fuel ran it and had no where near the power it did on 89 octane and the fuel jet that was a little lean. trying to fig out what happen here any help would be great

What brand plugs? Did you shut off the engine at the end of the run? What does the timing mark look like? Can you post a picture? Different brand plugs look will look different. I like NGK's, easy to read.

I do this when I'm tweaking the tune...


If you don't get help here, try yellowbullet.

[layinframe]

yes tried it at 5-6 psi but fuel pump couldn't hold both carb and nos so I went with a stand alone fuel system ran it twice on the 89 at 14psi switched jets got 91 and it had no were near the hp it did on the 89 and plugs I run ar135 gapped at 30. timing run 8 off nos 2 with nos

[70shortwide]

so do you have a dedicated fuel pump for the nitrous? Are you running this at the track or on the street?

[68 C-10 KID]

If you are wanting to run a hi pressure tune up call the manufactor and ask them for the jetting and bottle psi for a high pressure tune.
If they do not have one put the fuel pressure back down to recommend. you will need to get a tenth lb increments fuel pressure gauge and you will need to fully flow your system To tune the richness out .10 psi at a time.
Another thing is bottle temp. That has to deal with the tune up also. Different bottle psi is going to change the tune. So you will need a bottle heater and a gauge so you can purge the pressure down to same psi every hit.
Try the plug gap 25-28
Or as posted above Check out YB. Those guys have some fast stuff. And know there N20
Posted via Mobile Device

[stumpy]

Originally Posted by layinframe

yes tried it at 5-6 psi but fuel pump couldn't hold both carb and nos so I went with a stand alone fuel system ran it twice on the 89 at 14psi switched jets got 91 and it had no were near the hp it did on the 89 and plugs I run ar135 gapped at 30. timing run 8 off nos 2 with nos

You have to set the pressure with the system flowing! Is it dead headed or do you have a return? Also, do you have a test port after the regulator and do you have a flow tool? They're easy to make and it takes out the guess work.

What make pump and regulator? Believe it or not the cheap Holly regulators work great for this. Just make sure it's not bolted to the engine. It needs to be isolated from the vibrations, so hang it from the fuel lines if you can.

BTW, jet sizes mean nothing if you modify the system, i.e. change pressures, and not all companies jets are the same.

If you want to eliminate the guesswork, then send your kit to have it flowed. I sent my Big Shot plate and noids to a very popular N2O reseller. For $400 I got a completely calibrated system with all the jets and timing settings. He also gave very good support. When at the dyno and a tuner wanted to add jet to fatten the AFR, he said leave the jets alone and take out 2 degrees. The tuner agreed but said it would never work. Well it did. It fattened the AFR up nicely and it picked up ~50 RWHP.

[layinframe]

Originally Posted by 70shortwide

so do you have a dedicated fuel pump for the nitrous? Are you running this at the track or on the street?

yes pump and tank and the street

[layinframe]

Originally Posted by stumpy

You have to set the pressure with the system flowing! Is it dead headed or do you have a return? Also, do you have a test port after the regulator and do you have a flow tool? They're easy to make and it takes out the guess work.

What make pump and regulator? Believe it or not the cheap Holly regulators work great for this. Just make sure it's not bolted to the engine. It needs to be isolated from the vibrations, so hang it from the fuel lines if you can.

BTW, jet sizes mean nothing if you modify the system, i.e. change pressures, and not all companies jets are the same.

If you want to eliminate the guesswork, then send your kit to have it flowed. I sent my Big Shot plate and noids to a very popular N2O reseller. For $400 I got a completely calibrated system with all the jets and timing settings. He also gave very good support. When at the dyno and a tuner wanted to add jet to fatten the AFR, he said leave the jets alone and take out 2 degrees. The tuner agreed but said it would never work. Well it did. It fattened the AFR up nicely and it picked up ~50 RWHP.

pump is mrgasket 105p 14 psi no reg have all gauges and bottle heater no flow tool found how to make one and will be doing that this weekend

[stumpy]

Originally Posted by layinframe

pump is mrgasket 105p 14 psi no reg have all gauges and bottle heater no flow tool found how to make one and will be doing that this weekend

You must install a regulator. Without one you have no guarantee of steady pressure, or even the faintest clue what pressure you do have. I'm not sure anyone can help you unless you have one installed!

Does it still run OK on motor? Have you checked all of the plugs to see if any are missing the strap?

[layinframe]

Originally Posted by stumpy

You must install a regulator. Without one you have no guarantee of steady pressure, or even the faintest clue what pressure you do have. I'm not sure anyone can help you unless you have one installed!

Does it still run OK on motor? Have you checked all of the plugs to see if any are missing the strap?

runs like a champ its my daily driver yes I shut it down after every time I use the n2o pull all the plugs and inspect i have a fpss a/f monitor

[layinframe]

and yes i do have a holley dead head reg and a mr gasket return style just not on it

[layinframe]

update
put on reg and still same results come to find out my bottle didn't have a syphon tube so that's what was killing it turned bottle up side down and back to full shots

[BigDan3131]

Since you have a dedicated system for it I wouldn't just fill it with 91-93 I would just fill it with 100-110 just to keep you safer.

[71Dragtruck]

After the high octane square the jetting, you're using old recommendations and they are way too rich.

[Marv D]

N20 can be some really fun stuff,,, especially when you step outside the box of tried and true tunning.....

[layinframe]

Originally Posted by Marv D

N20 can be some really fun stuff,,, especially when you step outside the box of tried and true tunning.....

lol well im not lookin to step that far outa the box

[layinframe]

Originally Posted by BigDan3131

Since you have a dedicated system for it I wouldn't just fill it with 91-93 I would just fill it with 100-110 just to keep you safer.

kinda hard to find it here and what is here is 16 a gallon and can only buy it in 5 gallons at a time

[djracer]

Have you thought about using airplane gas on the the nitrous side. Here we ran roll up to the pump at the airport and swipe a card. The only thing it ask is for a tail fin number and I just make one up. The Av gas is. Little dry so I add a small bottle of marvel mystery oil to 5 gallons.
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[layinframe]

Originally Posted by djracer

Have you thought about using airplane gas on the the nitrous side. Here we ran roll up to the pump at the airport and swipe a card. The only thing it ask is for a tail fin number and I just make one up. The Av gas is. Little dry so I add a small bottle of marvel mystery oil to 5 gallons.
Posted via Mobile Device

no I haven't though of that but doubt id be able to get in the airport here think ill try it

[Sixshooter44]

The best thing you can do is get a flow gauge and go over to yellowbullet.com and talk to those guys, fastest and smartest guys around, just ask em.