Thread: Supercharger and Nitrous Oxide

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Anybody trying this with a roots-style blower? I am having distribution problems. 6 of the cylinders and fine but 2 of them melt the ground electrode.

Specs:

355 small block Chevy
Dart Iron Eagle 200cc Intake ports, heads 72cc chambers
Flat top pistons 4 valve reliefs
Performer RPM camshaft
All new valvetrain
B&M 144 blower with 7psi boost
32 degrees total timing

Heres what happens, launch at 2400RPM, nail it and go about 20 feet then engage the nitrous. Car goes like a freight train but starts to nose at 5500rpm. Shift to 2nd car pulls hard again but starts popping at top of 2nd gear (5500rpm), shift to 3rd pulls hard but halfway through engine lays over really bad and have to lift!

1. I tried running a seperate fuel system for the nitrous with race gas in it - no change!
2. I tried increasing fuel pressure on the nitrous side - car slows!
3. I tried increasing the pill size for the fuel jet in the plate - car slows!

Basically what I gather from this is that the car is not going lean? The car totally lays down in 3rd gear and is actually faster OFF the bottle! Is it detonation? I can't hear anything over the exhaust.

I need help with this before I tear something up. :0

If you want numbers, I went from a 12:28 off bottle to an 11:46 on it. MPH went from 111 to 119. My nitrous jets were equivelent to a 150hp shot.

You nitrous guys, please reply! Thanks....

Im having the same problem as of yesterday. The reson I found this thread.

Same thing happing to me. I had a 125 power shot on my car and the thing ran fine. But now I went to a 2 stage setup Im nosing at about 5000rpm. I also thought of a fuel problem so I installed a fuel cell and two fuel systems. Both running holley blue pumps threw 1/2 inch tubbing. Pressure is at 7lbs. Also installed a fuel pressure gauge and seems to be constant pressure. Im only using one side of that 2 stage at this time till this is fixed. Funny think is the only thing I did was take 2 degrees of timing out of the car and bolt on the new plate. I also in a 1/4 mile run melted off all ground straps on the plugs. Took the car last night to a 1/8 mile track and same thing happens nose dives and breaks up at 5000 however first gear seems fine 1.51 60 footers , But as soon as second gear comes blllllahhhh blllllahhh nose dives. Heres what Im going to do...

New carb tomarrow...holley 750 HP! I also went out today and bought a NOS delay box and a 4 step MSD retard box. Im running two colder then stock spark plugs. Going to 3 colder.

Again the wierd part is I only sliped a new plate under the carb. Sheesh making me nuts.

Have you had any luck fixing your problem?

PS...Great forum everyone...I'll be around more.

Oh ya heres my ride.. Only running a 7.25 in the 1/8 but think I can get to the mid 6's pretty easy.

Not everyone needs to go fast.

Nobody needs to go fast except police fire trucks and ambulances. The rest of us do it for fun and speeding tickets. Adding nitrous to a blown engine seems like overkill to me. If I wanted to race you guys I"d get me a jet engine. To hell with the aftermarket parts. You guys are using old technology. The land speed record was set by a jet engined car. Has anyone tried nitrous on a jet car yet?
AL

Still working on the problem, Thanks for the help so far guys.

I built the bottom end to the hilt. The bottom end is stronger then the block itself.

Ya speed is cool, Getting there in the fastest time possable is even better.

Hi...what are you using to pull out timing??..I think you need to retard timing some. What kind of fuel are you using??..

Im running 112 and to pull timing out Im using a digital mutli retard box. I upgraded the ignition to all new MSD and seemed to fix my breaking up problem. I put on a new carb last night and going to the track today to test it out. Let ya know what happens.

I'm wondering what induction your using(carbs or Enderle hat)?

What kinda N2O system(Plate on top of huffer or Fogger)?

I ask because if you are using a plate kit on top of a huffer, it really messes with the fuel/air supension when it get pushed around the lobes and all, Fuel has alot of time to fall outta supension(I perfer a Fogger setup in the intake runners just north of the port nozzles.

If you are using a injection hat instead of carbs, well the benifit of the hat is a scopping effect, draw back is, the air collects to the rear of the engine.

Just throwing out some stuff to get you thinking more about your combo. It sounds like your going lean on the 2 cylinders.


Ohh yeah, on boosted aplication made you should use a ignition box that retards timing in relation to boost like the MSD 6 BTM
and then use a fixed retard box that will pull a fixed amount of timing the instant the Spray is activated.
pull 2 degrees per 50hp of Juice... and then a additional 2 degrees of a safty margin.

150hp = 8degrees of retard for the nitrous alone...

Hope some of this helped.

My Old Car... I still have the Engine and tranny..LOL

Twin Predators..


Injected....

Thanks for the reply. I think I got it fixed. I upgraded the ing system (and a hole bunch more) And seems to be running pretty good. I got a 6.78 in the 1/8 with a 1.51 short time. Not to bad for my street car on 10" tires. Im pretty happy. I will be upgrading cam and heads this winter and installing a fogger system on it. I hope to run a 6.3 and will settle for a 6.4 but who knows.

Nice ride you had... That motor would look great in my car.