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Nitrous system upgrade

6K views 9 replies 5 participants last post by  carl nolen 
#1 ·
Hello. I am running an old NOS Sportsman Fogger System with 30x32 nxf jets. According to the manual I will not achive more hp if I run larger jets and the kit needs to be upgraded. Which parts do I need to change?
Best regards
 
#7 ·
Carl,

I am from Uruguay in South America. For your last question, don´t laught but we don´t have a drag strip in owr country (3rd world country). We race in the only race track we have. No times with this set up. With 11.7:1 cr, 48 idas, msd ignition, stock transmission, 26x6x15 dot slicks, belt on and 75 shot, the 1/4 mile time was 12.10 and speed 110 mph all motor, 11.70/117 on the button . No traction at the track (similar to the street).

The car is a brazilian sedan, all steel body, 2" narrow front beam, 1" RLR trans raise kit, actual weight is 1760 lb with me in it. Transmission is from KCR with Wedle gears. 3.4 2.17 1.6 1.22 with 3.88 r&p. 26x8x15 slicks.

Engine is 94x82, CE 44x38 ported and polish, 13:1 cr, fk89 cam with 1.4:1 rockers, ms3 secuencial fuel injection and ignition with 48 mm throtlle bodies, 80 lb/hr injectors, 1 3/4" cheap merged header.

The nitrous system is the old Sportsman Fogger kit for VW flat four from NOS with a blue pump, regulator and tank for it.

Some pictures:







Regards
 
#8 ·
Very nice setup. I do not see your solenoids in those pictures. With the NOS sportsman system, do you run two Power Shot or four Power Shot solenoids? If you run one Power Shot nitrous and one Power Shot fuel, you need an upgrade. The Power Shot are the small NOS solenoids. I have run two different systems over the years. Two NOS Cheater solenoids in the center of the motor, like this:



That's an old picture from 2007. I have cleaned it up a lot since then.

The #3 flex lines are 16 inches for nitrous and 15 inches for fuel. I would not run a fuel hose longer than (a total of) 16 inches from the solenoid to the nozzles.

And, I have run two Power Shot solenoids at the nozzles on each side of the motor for a total of four solenoids. The largest nitrous jet I have run is a 21. I know of another car here that has run 26-28 nitrous jets at times. It's not common to see a VW running jets over 30. There has been racers who have, but not real common. I believe in the 30 jet range, you are at 200 hp area. A lot of juice for us.

So, to answer your question, you could run two NOS Cheater solenoids in the center of the motor area and keep your flex lines as short as you can. The flex lines work for me and very easy to use. Some people do not like them as they had rather use steel lines.

You have to be very careful with the timing on our motors with big jets. Hi compression, small combustion chambers, steep valve angles, I feel we have more in common with the nitrous motorcycles than the v8's. I used to watch the ADRL Pro Extreme Motorcycles for their nitrous setups. They ran a lot of juice on their bikes with a Schnitz controller.

If you do not have a Progressive Nitrous Controller , you may look into it. It sure will help controlling the nitrous in first gear with big jets. I do not run one as I have not run enough jet yet to over power the car in first gear. But, I may need one with what I am planning.

Carl
 
#10 ·
Hi Jared. I really do not know the math behind flow rates of solenoid orifice size vs jet sizes. I have looked at the math but not have studied it. There are several racers here in UAC that really get into the science of that. I have seen the basic NOS Sportsman system with one set of solenoids and four nozzles. I believe that system is rated at 75 hp max. The NOS Sportsman system with four solenoids I believe is rated at 150 hp max. The four solenoid Power Shot system is the more common one as it is designed to have the nozzles and solenoids mounted on the outside of the manifolds. Lots of racers have used that method with the nozzles on the outside or inside of the manifolds.

If you are running one set of Power Shot solenoids, you may have to contact NOS or Nitrous Supply and talk to the people that really know that. I have run the four solenoid system and have run a 21n and 20f with those and have been just fine, which is about a 90hp tune.



That pic is when I ran Unlimited Street. It is the four solenoid system as I added a fan housing to be able to run that class. That setup worked great, as long as you have the fuel solenoids right by the nozzles. My first design of that system used two Cheater Solenoids. Well, I mounted the fuel solenoid way too far from the nozzles with about 20-22 inch lines. Rattled the motor big time as the fuel took way too long to reach the nozzles at 7 psi vs 950 psi of the nitrous. In the previous pic with the solenoids in the center of the motor with 15 inch lines, I did not have that problem. So, that is my reasoning for keeping the fuel solenoid or solenoids as close to the nozzles as possible. To me, you could run a longer nitrous line mainly due to the pressure nitrous runs at. Fuel doesn't move all that fast at 7 psi. You will hear racers talk about a lean spike on activation. How you apply the fuel has a lot to do with that.

The 2007 pic is my first setup. Home made system I built with the help of Gary Calvert, onjuice here on UAC. Pretty much duplicated 1/2 of a v8 system. We thought we may run in the 150-200 shot area and wanted to have enough solenoid to support that. I've run the same times with both systems jetted the same. 10.48/6.46 on both designs. I have since taken the fan housing off and going back with the two solenoid system in the middle later this year.

Those are not "plates" you see in the pic. Just spacers with nozzles screwed in. They work great. Again, home made.

Carl

And, juice it HARD baby
 
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