Nitrous in 2007 rubbermount

[Kot]

Hi guys !

In last days I start working with nitrous kit for my Fi XL .
(I bought DynoTune race bike kit in last year)







and my crappy Tig welding :










and my friend on my (almost) NITROUS BIKE



I can't use my pressure regulator, it can't work right with liquid ...
so I will must check bottle pressure before all nitrous runs...

I want put nitrous nozzles in intake , like fuel injectors direct to valves but I can't find enought space for do it (maybe with diffrent nozzles but $$$) .

In the other hand when we spray nitrous before throttle body it can by better mixed with air
(I think it is important with small HP gain 10-15% )

Instalation will by connected to the Thundermax ECU for extra fuel and
less timing ... anyone know where I should set timing ?
100HP 1200cc , se 536 cams , Hammer Heads , 10.5CR Forged CP pistons , STOCK BOTTOM END
RON 99 gas and 10-15HP nitrous shoot just for better 1/4 mile ET
I plan dyno testing it and start with 25deg flat on nitorus and of course above 4500RPM

In the next week I will do electric connections and I hope I don't blows up my engine on dyno before race...

IF anybody can help me or I do sometching wrong , I listen to You XLF guys

[Screw Loose Dan]

I'm surprised no one chimed in here, but I don't have any advice to offer either. :S

You may want to PM JasonSarratt on here. I would *suspect* that timing with the 10-15 HP shot would be similar to timing when running under the boost of his turbos.

Understand, I have no idea and ZERO experience...seems to me that 10.5 CR is kinda high for running nitrous?


Please keep us posted!

[Kot]

Thanks for reply Screw Loose Dan !

10.5 CR is the reason for 99 RON gas ( in USA super premium 95 octane )...
(my engine runs well with 95 RON -in USA midgrade 89)
With this gas and retarded timing (25deg max adv.) detonation shouldn't be problem ...

I think 10-15% more power with nitrous should be safe ...

I read about guys doing 120HP with stock bottom end in rubbermounts...
so I hope my connecting rods can handle 110HP ...

I have jets for 10-15-20-25-30-35-40 HP and I will try the smallest with :
-very low nitrous pressure (bottle in the fridge )
-retarded timing
-fat AFR :11.5 with nitrous... ( I will start with +20% injector pulse width )

http://www.schnitzracing.com/technical_corner.htm

I will post my experiences with nitrous on dyno and I hope on the track ...

Kot

[norseXL]

Dont know much about NOS but you must be shure to add anough fuel to go with that NOS or...

[Kot]

I check today data logs from my thundermax...look like on 6800-7000RMP my injectors work at 90% duty cycle :/
I def. need bigger injectors !!!

anybody known that this :
PN 27796-08 SE injectors 5.3g/s
or
PN 27797-07 SE injectors 4.9g/s
or
PN 27665-01A V-rod stock injectors 4.81g/s

will fit to 2007 sportster ?

[HandOverFist]

Kot - It looks like you are basicly going to be running a dry nitrous system. For small shots I think your timing will be just fine as it is n/a. Just start small and listen/check plugs after a run. A cold bottle won't be worth a damn...gotta heat it up to at least 900psi...a hair dryer will work in a pinch on a small bottle. Maybe fatten up afr's at WOT if needed. The ideal solution would be to use a progressive controller...I have one here I might experiment with at a later date.

If possible use teflon paste intead of tape...tape often flakes and plugs the small orifices. You might try at first just activating in fourth and fifth gear to get a feel for it...maybe use the horn button along with a WOT microswitch.

Not tried this on a bike yet, but do you think spraying the cold in the throttle body will trick the ECM into richer afr's like it does for the efi cars?

[Kot]

Originally Posted by HandOverFist

Kot - It looks like you are basicly going to be running a dry nitrous system. For small shots I think your timing will be just fine as it is n/a. Just start small and listen/check plugs after a run. A cold bottle won't be worth a damn...gotta heat it up to at least 900psi...a hair dryer will work in a pinch on a small bottle. Maybe fatten up afr's at WOT if needed. The ideal solution would be to use a progressive controller...I have one here I might experiment with at a later date.

If possible use teflon paste intead of tape...tape often flakes and plugs the small orifices. You might try at first just activating in fourth and fifth gear to get a feel for it...maybe use the horn button along with a WOT microswitch.

Yes, I will use dry system , but with thundermax I can add extra fuel
with stock injectors only when I ran with nitrous . The same thing with timing , 25deg only with nitrous and auto activatad nitrous only on WOT and above 4500RPM...

My problem is that my stock injectors are too small , my engine make ~100HP
on 6000RPM injector duty cycle is above 80% on 6800RPM injectors work on 90% ! Injectors shouldn't run above 80% duty cycle...

It doesn't matter what I do , change the tune for fat AFR or spraying nitrous direct to air temp sensor , ECM will try add the fuel but injectors will can't do that .

so anybody know that
PN 27796-08 SE injectors 5.3g/s
or
PN 27797-07 SE injectors 4.9g/s
or
PN 27665-01A V-rod stock injectors 4.81g/s

will fit to 2007 sportster ?

[HandOverFist]

Let's ask Jason about the injectors he has been using in our turbo's...they are from a turbocharged Volkswagon. He can tell you what the values are specifically and if any of those you listed are comparable. I'll message him and send him to your thread.

[JasonSarratt]

They are a 6 hole pattern, no shrouded nozzles, the spray plates are custom drilled so each set of 2 are flow matched. They start at what HD would rate 6gs and I've ordered as big as 8gs... I'd have to check records but Ricks are 6 or 7, all the turbo 1200 bikes are 7gs....

The lil Ports help them tune out real clean...hell people would prob tell you you'll never get 6 or 7gs Injectors to drive nice low end on a lil 883...

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[JasonSarratt]

On another note... Kot I love what you are doing, I played with nitrous a lot and it was fun... I am in no way telling you not to, just sharing my thoughts.... Personally, do not trust the tmax for fuel control with spray...honestly run a wet system. I know lots of people who have used dry systems and lots who have used wet, I personally always ran one wing per port. Running one power wing in the center works ok but might show to be a tad sloppy but will still work. With a wet kit you tune normally as na and the fuel will always be there mixed with yer nitrous hit...never have to hope retune or pray...also run a pressure switch on the fuel side that kills the nitrous solenoid should pressure drop

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