[godsend]

http://www.brillko.se/LM1-NOS.GIF

http://www.brillko.se/LM1-NONOS.GIF

look at these picks and you will se how much it pendning.

I dont feel this so much under the run, but it dont answer to any more nitrous. Running faster with 100hp than 225. So i looked in my logs and found this.

Runs perfect without NOS as you can see on the other pic.

Running Powershot N20 and Cheater Fuel Solenoids.

A BG 220 fuelpump and regulator. AN10 delivary and AN8 Return.

Can fuel solenoid Fluctate? Will it do so before Nitrous starts fluctating. Have 13.8v+ whole run.

Can a N20 Plate under my MAP-sensor give it signals so it thinks i have 2psi or more BOOST?

If it thinks so i can map these curves. because, they are lean. ( I dont use any boost)

Hoping for some answers because its not very fun ;(

 

[Doug F.]

Does the lambda reading stay flat when you are on the carb only?

I've never really seen anything flucutate like that. I wouldn't guess you would have problems at that HP level.

 

[bigjimzlll]

are you running a Hobbs switch?

 

[godsend]

Hobbs? Is it Low pressure cutout switch?

Yes and No... I tried to disable it, Same problem.


The second pic is without NOS. So stable it can be on a 9 sec run...

 

[godsend]

http://megageekboy.ramnet.se/filmer/close_call.mpg

This is a video of that run.

Im gonna flow my system tonight. I heard that 1/5 relation i what i need between fuel/nitrous.

So that is what im going to flow it to.

I have another though, my NOS fuel cell has its outlets towards the front of my car. Can it be a such thing?

 

[1bad67]

What is lambda?

 

[Bobalos]

If you average it out, it looks pretty fat on the motor (not a bad thing), but those spikes lean could be the death of the motor.

how old are the noids? could they need a rebuild?

are you running a progressive controller?

what does the fuel pressure look like the entire run (I know hard to watch fuel pressure, shift light & the road @ the same time, maybe time for a run with a passenger).

do the plugs look OK? are you getting any detonation when it goes lean like that? as lean as it goes, I would think that you would.

Bob

 

[66 283]

godsend,

it appears fat to me on the spray, less the spikes - what do the plugs look like? With that small amount of nitrous I would expect it would measure about 11.5:1 A/F and that appeared to be 10's. (isn't it lambda x 14.7 = A/F I think?)

The lean spikes - I wouldn't worry about them too much. Your fuel systems seems more than adequate - do you have the hot side of the solenoids through relays? Do you have a means to log fuel pressure? More importantly, what do the plugs look like?

 

[69 Ratt Vette]

With everybody else, what do the plugs look like? I don't think the fuel cell pointed the wrong way is a good thing. There is so little fuel volume in a small cell there is a chance it could be spashing around and intermitadely starving the pump.

 

[godsend]

Plugs is perfect. Leakdown is under 5%

I got a MSD7AL3 with ProPower Coil and MSD Probillet dist so it fires everthing i put in it.

Fat i know, but i dont wont to lean it out when i see these spikes.

Solenoids are 4-5 years old. I bought 2 new Nytrex kits. Mounted it up today. Going to flow it tomorrow.

I do a testrun on friday. Hopeing to lowering my times a bit. Spraying 150+150 on friday.

Plugs are NGK 7:ens.

 

[66 283]

I'm no expert, but I would go with a colder plug - I use 9's or 10's by NGK (5671A-9's or 10's)

Fat is safe but PIG fat can be as dangerous as being lean. 5:1 is still pig fat at the lower horsepower settings - I had my system flowed by applied and it works very well (www.appliednitrous.com).

Just curious - how are you going to flow it? Through the jets and weigh the fuel and nitrous used? I'm thinking about building a flow bench in the garage but it is at the planning stage.

If you are running 150 plus 150 why don't you run one 300 stage? 1 stage is always safer and easier to tune than one stage. You have big tires and a 4-link don't you?

 

[godsend]

Yes 17" inch 33" slicks and no grip problem. Execept when streetracing.

Then i cant use a 300shot from start. Becasue of that i use twin 150 and @ strip i use both from start.

Going to weight gas and fuel after 10 sec.

So 5:1 is a fat jetting?

Last year Flyboys told me to lean it out. Man what a punch i got ,) Used NOS jetting table and that is fat... So we tuned down to a 4.75 psi fuelpressure and 930psi nitrous pressure. Wow

So what is a good relationship on a smaller (300) shot? Going to use 73/65 jets on both plates with 73 on fuel and then regulate my pressure on fuel to get right relationship.

Plugs, i could try colder plugs. Cant se problems with them though?

BTW, Hoping to gain topspeeds. So poor now. 218 on motor and 222-226 with N20 only gain 4-8km/h and 10-16km/h@201 where i have 174 on motor and 184-190 on NOS.

 

[Doug F.]

I've used the lambda readings to tune 100-400 HP nitrous tuneups and haven't been steered wrong yet. The only thing is if you have the O2 sensor in the collector you still should pull plugs to make sure you don't have a problem cylinder or two.

I still am conservative though, but try to run around 10-11:1 A/F ratio with big (300-400)tuneups and 11:1 on pump gas 100-150 tuneups. You can go leaner, but those give you a good margin of safety.

 

[godsend]

Cant get anything higher than 7.ens with 5/8 head, non resistor, non projected in europe.

 

[godsend]

So with a twin 150 shot i should be around that lamda i got now. 10,5 AF

 

[66 283]

I concur with Doug - go with plugs first, then see what the o2 says and you might not care.

I went back and looked at my numbers - I ran a 5:1 n/f ratio as measured by appliednitrous.com on a big jet, (41) and it read fatter than I remembered - it read an average of 9.59 A/F from 5200-7000 on the dyno. It made a lot of power but made black smoke like a diesel. I had to keep it that way because of the 93 octane fuel.

There is a good post on gofastzone.com in the nitrous section about what air/fuel ratios are on big tuneups - apparently the promods run them low 9's but the more nitrous you use the more the readings are skewed low because of excess nitrogen.

I know of people who are running 100-200hp on the dyno and tuning up to A/F's around 12.0:1 so the more nitrous you use, the more it is skewed.

So the bottom line - on that jet at a 5:1 N/F it was VERY safe - next time out if i run C16 I will start dropping the flowing fuel pressure and report the results.

BTW, the hp numbers are funny because I exceeded the dyno RWHP limit.

RPM RWHP A/F
6,057 908 9.26
6,089 448 9.35
6,119 939 9.21
6,184 916 9.76
6,188 987 9.28
6,250 1,020 9.42
6,238 699 9.44
6,334 1,278 9.64
6,373 1,086 9.97
6,471 1,342 10.14
6,509 1,712 9.55
6,504 85 9.65
6,415 447 9.64
6,475 644 9.56
6,520 781 9.61
6,509 1,077 9.83
6,660 1,299 9.83
6,619 1,062 9.61
6,690 851 10.09
6,850 2,171 10.26
6,870 1,518 9.57
6,744 90 9.82
6,760 27 9.82 <--- flat spot apparently
6,859 1,268 9.79
6,815 823 9.92
6,870 861 10.01
6,960 1,669 10.03
6,945 514 10.27


http://elbowsandassholesracing.com
under construction

 

[godsend]

So you are saying i try a 5:1 Setting, And add/remove fuel and look at plugs/Trapspeed to see what is the most effective way to go!

 

[66 283]

godsend,

I'm curious how you are going to accurately measure N/F ratio - you will have to waste a few pounds of nitrous to get a decent number. Are you going to flow through the plate into a bucket or just through the jet? While you are at it I would map out a few different flowing fuel pressures so you will know how sensitive it is to change.

FYI Applied mapped out the N/F ratio from 5:1 to 6:1 in 0.5psi increments - but I have a high pressure tuneup 10-15psi - you would need to go in 0.25psi increments

I am thinking about rigging up some timers and a laboratory scale so that I can get repeatable results in my garage.

And this goes without saying, but pull ALL plugs after a run with a plate. It will go the fastest when it is using the "silver" fuel. LOL

 

[505Nova]

Godsend sounds like you have the same problem I've been running into last few passes out. I'm finding out how nice it would be to have a good datalogger on the car cause all I can do is read plugs and guess at what is making it surge.

Please post what the problem is if you find it, might give me something else to look at on mine.

 

[godsend]

im just going to weight it, Install bottle open it, close it and weight the "waste"

Install, flow trough plate in air for 10 sec with timer.

Then flow Fuel. I only need one flow for each jet of nitrous.