Mr Y Car

Finally have FRED and the NX Nitrous system installed on my ZR-1. First impressions were to wonder whether it was on. THe ZR-1 was quick, but the intial 100hp shot felt the same as stock. Well that is until I looked at the speedo.

This system rocks. FRED permits you to gradually add the HP. It pulses the solonoids and the HP just kind of sneaks up on you. Played with a few cars with it over the weekend and WOW. They were really toast.

I have used NOS systems in the past, and they seemed to just WAM the HP on you. THis FRED (Maximizer) just is the cats meow.

Tomorrow I am installing a 150hp shot and see if I notice the HP more.

USAZR1

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[This message has been edited by USAZR1 (edited 07-11-2001).]

USAZR1

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[This message has been edited by USAZR1 (edited 07-11-2001).]

Mr Y Car

am running fred at a .5 second delay, 40% slope and ending at 100% with a 2 second ramp, and 10% reset rise.

My system didn't come with any fusable links, but I went and purchased some. I initally started with 15amp fuses, but blew them the first run. Am finding good luck with the 25 amp fuses.


The system is working. I notice it is faster. The HP is added so smoothly that it just doesn't seem to be there.(but it is) Heck, I had to do some dry shots with the engine off to determine it was working properly, which it was.

So far am happy with the system. Am just surprised on how smoothly it adds the HP and at how little I really notice the new HP, unless I look at the speedometer.

Mr Y Car

Took the car to work today, ran up against a BMW m5 that wanted to play. Turned NX system on and let it go. Was pulling strong in fifth, when a big fireball emitted from under the hood followed by a large bang. Being on a four lane road with no place to turn off, I limped the car to work expecting a blown vacuum line. The car was running just like it had no vacuum.

Park car, open hood and look at what used to be a plenum. A big hole was blown through the top.

So now to get a tow truck to get the car home. Then go looking for a another ride. As big as the hole is, I suspect there probably is internal damage.

NX isn't too fun now.

ZR1

I am not a huge critic of NO2. Matter of fact I have often considered it on my car. What I don't understand is why is it that everyone I know who uses it has blown an engine? They swear by it, it's a religious ferver with some, but all I know have blown the engine up. It may be something as small as a burnt valve, or it may be something as violent as blowing holes in the top of pistons.

Anyway, add another to the list.... Cha-ching

JT ZR-Won

Aw man....that sucks

Phil DeJohn

Cheap HP ends up costing BIG MONEY.

4cefed

Why do you think XSMPH has had such good luck? Just asking the temple minder. What is it about the LT5 that makes it give up the ghost on the juice. Is it the timing set too high? Are people hitting it at too low an RPM, which it sounds like what happened in this post if he was gassing it in 5 gear

Mr Y Car

who said my rpm was low? My speed was high.

RatRacer

Michael, the minimum rpm for nitrous is 3000rpm. If you were in fifth and you were at less than 3000rpm, then that is a possible explanation for what happened. Most people do not juice fifth gear.

Cameron

4cefed

What RPM in fifth were you? Hey, sorry to hear what happenned, I feel your pain.

Mr Y Car

Lets just say I was over 3krpm.

Mr Y Car

The microswitch is still on the Throttle body. Was going to move it to the firewall this upcoming weekend. Don't think I need to now.

Looking at the damage done to the plenum (pictures coming soon) it shows the risk of running a wet nitrous system. A small spark from something is all it takes to kill the plenum. The plenum was never designed to be a combustion chamber.

All eight cylinders are firing. I am hoping the plenum is the only major physical piece of the car damaged. It is surprising the car ran so well with such a large hole.

Looks like they'll be two dead ZR-1's in Dad's Garage. Anyone want to come up and see the ZR-1 assembly party when I fly Skinner in to assemble the engines?

Now to avoid the more Cubes fever.

FastZR1

Oh man, this is not sounding good at all!
Keep us posted on what you figure out the problem was.

USAZR1

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[This message has been edited by USAZR1 (edited 07-11-2001).]

RatRacer

Michael, before you start to pull the engine I would suggest that you replace or repair the upper manifold and run the engine. Do you have access to your dad's manifold? I've seen a number of manifold explosions that did not damage the engine at all. You said you have run the engine already so I doubt you hurt it at all. It is worth trying before you start pulling another engine.

Cameron

Mr Y Car

I am not intending to complain about the NX system. Just trying to diagnose, what the cause is. There is no flaming of the product at all. I am just stating facts. I always learn things the hard way.

Somehow a spark, caused the now fuel/ air rich mixture to combust in the plenum.

This probably was not the nitrous systems fault, but the combustion in the plenum was. Probable causes of spark could be a backfire, to blow-by from the valves. Of which the a/f ratio introduced by the nitrous may have caused a lean condition resulting in backfire, which caused the plenum to explode.

I suspect that whatever caused my engine to perform so poorly at BG probably probably caused the condition that killed the engine when combined with nitrous.

This is just speculation, I will consult John Stewart when it is time to analyze the engine.

USAZR1

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zrchris

I see you've found out the same as others why the wet system NX sells is not good. NX's approach has hurt plenty of parts. The LT5 plenum is especially too large to sustain the velocity needed to keep fuel mixed well in the stream, and so fuel drops out. Then the mixture's not right and a reversion occurs, say goodbye to the top end. NOS says the wet approach is tolerable at high RPMs with around 100hp shot, but is a bad idea on a large plenum.

The only true professional way to do it is dry, and add the fuel at the fuel injectors. GM contracted NOS to produce this sytem originally, and it is highly reliable over the RPM span. This isn't trivial to control though, and I advise just buying the NOS kit for this. If you want to add more than 130 hp or control it with a progressive controller, put a fogger nozzle in each secondary port. This will make it a whole independent system that is downstream of the plenum and safely allows higher power levels with guaranteed distribution. Anybody's parts will do fine for this approach.

Chris

[This message has been edited by zrchris (edited 07-09-2001).]