Thanks, Yeah I know about the Fuel preasure safty switch, and the window switch, I am also getting an air/fuel switch as well, which will shut off the nitrous if the air/fuel ratio becomes to lean or to rich. This should compensate if the fuel preasure drops for any reason, because the O2 sensor will get lean readings even before the preasure drops to a grenade-the-engine level.
If the injectors suddenly locked or such, that would mean fuel pressure would be 0 and hence the FPSS would kill the N2O, right?
Also some FPSS are ajustable, so say I set it at 60 or 70psi so the N20 will cut if it drops, problem solved.
I just dont think that a company, such as NOS, would put out a kit for a specific engine/car(lt1 corvette specific kit) if they thought even 5 percent of the time that engine would die.
Oh well, i'm not looking at a huge shot of N2O, just 100hp every once in a while, I shouldn't run into anything major.



[Modified by enhance, 1:54 PM 3/27/2002]

 

You "shouldn't" have a problem with a 100 shot...Even dry, but I would still install a booster pump, particularly with a dry kit. With regards to Holley (oops, I mean NOS) I have both good and bad things to say about them. As an NOS dealer (we don't sell any other) I like their product for the most part. As a general rule it's VERY well engineered, but they have taken shortcuts in the past. A good example of this in my OPINION is the dry LT1 kit. This was originally done because there was a "percieved" problem with fuel puddling in LT1 manifolds which turned out largely incorrect. I mean think about it...The TPI with its LONG butt RUNNERS is a wet system and it has NO puddling or fuel distribution problems, nor does the LS1...Now, why is it that the big plenum, 3.5" straight runner LT1 does?? Answers simple, it doesn't...NX figured this out, NOS didn't go back again because the technology worked for them for the most part and it would (in their opinion, I think) require too much redistribution of capital to reengineer the product. But, honestly I've been using the 5151 on the LT1 and have NEVER had a problem!! Once again, I don't sell NX, just NOS but I've talked to both of their tech gurus and engineers at SEMA before. And honestly the newest player out there; Texas Nitrous Technology (TNT) looks very promising to me. But, the fact that NOS was the pioneer in the nitrous business kinda keeps me with them... Incidentally I honestly wouldn't bet the farm on the A/F meter giving you a safety margin. Unless you're using a wideband sensor. OEM standard (non-linear) O2's are VERY inaccurate +/- about 3% to either side of 14.7:1, which is stoichiometric. If you see 14.7:1 on a nitrous sniffer, it's already too late...
-Jeb Burnett

 

Thanks for the input.
I will most likely install a booster pump. I am also getting the MSD digital 6+ ignition to retard the timing when the N2O hits. Anything else you think I should get?
So do you think the air/fuel switch is a waste of money? I just want to do it safe(still with the dry kit though).


[Modified by enhance, 5:14 PM 3/27/2002]

 

No, I wouldn't waste my money on the A/F switch unless, like I said, it features a linear (wideband) O2 sensor...And the cheapest I've found them for is close to $500 but I've yet to see one so I don't know if it's nearly as accurate as the $2Kplus Horiba meters. But, you're definitely going in the right direction for N2O use and safety (I'm keepin' my damn mouth shut); an upgraded ignition will be a great addition, particularly with the retard function. 2 degrees of retard for every 50 hp of N2O is the industry standard; it's conservative, BUT DON'T SECOND GUESS THEM! Go to one heat range colder on your plugs and you may want to narrow the gap slightly. Seeing as how it's a cast piston motor, don't go over 125 on the N2O (I steadfastly refuse to get into my "150 seems to be the magic number" diatribe on here for fear of starting another argument like the one above). The most critical aspect you're going to run into is fueling...That booster pump will keep you from picking the guts off the street (hopefully...I know, I know, I'll shut up now).
-Jeb Burnett
PS- I thought of one other addition that will give you a margin of safety that the A/F "says" it gives you...An EGT probe in one of your exhaust runners. It doesn't have a switch to shut off the system, but if you pay attention to the exhaust temps you'll know when you're going to have a problem. Put the probe in the hottest cylinder, usually at the back of the block; #7 is where I usually put it. A little race gas (VP Performance Unleaded or comparable) never hurts either!!

 

RatRacer, Take a chill pill. Your ZR-1 experience, with nitrous, has absolutely no bearing on the L98/LT1 motors. You have a totally different motor, intake and fuel system. What works on your ZR-1 may not be as safe as on a LT1.

jburnett was just stating his experience with nitrous. Feel free to share your experience, but please respect someone elses opinion.

Personally, I like the wet kits for the safety factor. Sadly, I'm going to have to sell my NX kit due to being laid off. When things get better, I'm going back to the NX wet system. I like knowing I have a seperate solenoid for the added fuel and not taxing the stock injectors. But hey, that's just me.

 

Thanks, jburnett.


[Modified by enhance, 5:13 PM 3/27/2002]

 

This is something we agree on. A plumbed fogger set-up is without a doubt one of the best ways to run nitrous. I plan on this set-up for my car in the future.

BTW, I'm not upset with your views. I think we'll probably agree on most high performance issues. This just isn't one of them.

 

...and I agree w/ all of JEB's points here too. All good suggestions.

 

...but just for kicks, here's what a wet manifold nitrous backfire looks like on a ZR-1.
http://forums.corvetteforum.com/zerothread?id=96398

That manifold retails around $2k. :eek:

One of reasons Jeb dislikes dry systems is a number of failures he's seen on imports with a little 75 shot. Well consider that a 75 shot on a 2.0 liter ricer is the equivalent of a 214 shot on a 5.7 liter Vette. No wonder they blew up w/ the dry system. I'd use a wet system in that application for that much power.

Like I said before. There are applications were a dry system will work just fine. It has it's limits at around 125hp for a typical 5.7 liter production engine excluding the LS-1. For over 150hp I would plumb a direct port fogger system although a single or double nozzle wet system will work by throwing a bunch of fuel in the plenum. The risk for the wet manifold system is pictured in the link.


[Modified by RatRacer, 9:44 PM 3/27/2002]

 

JEB,
I've been looking at the new Gemeni Twin Mass EFI system by NX. Are you familiar with it? Also the TNT LT1 system looks pretty good. Appreciate any insight I can get on these systems.

:seeya

 

I do indeed have custom tuning in my car for injectors, different cam, ported heads etc....
If your car is stock except for the nitrous and you are not gonna be hitting it with a big shot, then your stock 24# injectors should be sufficient, if you are gonna make an upgrade, go with the 30lb and have a custom prom burned for your car. Make sure to go with a non platinum spark plug ( I like to use an NGK TR-6 that is one heat range colder than stock) that is gapped at .035-.040 Since I have my car tuned to run well on motor, I use a MSD digital 6 ignition and I pull 4.5 degrees of timing on the bottle. It would not hurt to upgrade the fuel pump in your car either, it is a very easy job to replace the intank with a bigger walbro unit. You can order one from Speed Inc. 847 891-0767 (this is a speed shop located by my house that does alot of internet business and has great prices).

Mike

 

vetsvette, the link I posted above with the manifold explosion was a NX Gemini Twin set-up. The second page gives you a good pic of the double nozzles.

 

The only 'real' experience I've had with any of TNT's stuff was a display at SEMA I think, and a conversation I've had with them...They certainly talk the right talk; we'll see how long their stuff lasts. But, I for one am fairly impressed with what I've heard from them. As for NX, I really have no experience with their Gemini Twin, but it looks promising as well...But keep this in mind, cast pistons and 150+ shots (and I believe the Twins are for pretty big doses, right?) are like oil and water; you can mix them but not with good results. As for the rest of the NX stuff, I've had pretty good luck and feedback over the few I've done. Like I said, I'm primarily an NOS dealer but I've sold some NX kits when customer's have specifically asked for them. I think they've probably got some of the best LS1 stuff out there and their R&D department is very good.
RatRacer....We're cool, I understand where you're coming from...I've actually been thinking of building some either Fogger equipped spacer plates or maybe even a spray-bar spacer for ZR1's...Are you or anyone else out there possibly interested?? Put an EGT on that Zed, though...Please...I KNOW HOW MUCH AN LT5 COSTS!!! Oh, and one other thing, actually the majority of the dry kits I've seen come apart have been domestic V8 applications. But they are quickly being overtaken by imports with ZEX kits which seem to be true pieces of poopie...I don't sell 'em, but I get a lot of grief from dealing with kids living their 'The Fast and the Furious' fantasies bolting them on and thinking they're Vin Diesel!!!
-Jeb Burnett

 

You have mail.

I tuned my car on a dyno with a wide band O2 sensor and I have good a/f ratios.

A spray bar spacer may be a good way the go because you can do it with 1/4" stock, although I know an individual that plumbed foggers in a plate on his ZR-1. Someone in Arkansas did it for him. The problem is hood clearance. Any thicker than a 1/4" or so and the plenum rubs on the hood.

I'm interested when you are. :cheers:



[Modified by RatRacer, 1:24 PM 3/28/2002]

 

Lemme guess...Callaway SuperNatural ZR1??? Pretty trick cage he's got in it now too, huh? You can actually still put the targa top in the back with it and the removable door bars were a PITA.... That's Bobby Shahan, Shahan Race Cars...One of my close friends, our chassis builder, and the driver of our Super Stock 66 Vette!!!! I was present throughout almost the entire work. He did an EXCELLENT job with that plate but there are actually a couple of things that 'could' be changed. You can stay with a 1/4" plate with the Fogger; it will be simply the 1/4" plate between the runners to keep the height down but will have a 3/8" lip to the outside for the Fogger nozzles. Only problem with doing a plate type application will be the spray bar...But, I suspect I can get NOS to make me some to my specs...
-Jeb Burnett

 

That's the one. The cage is very well done. It almost looks like a factory install.

Christopher's fogger set-up is excellent. The only downside is that it impairs access to the spark plugs somewhat. A spray bar plate would really clean up the plumbing and leave the area over the plugs clear for service. Let me know what you can do.

 

I'll check with NOS about making me some spray bars...I've got a LT5 plenum gasket set and maybe a phenolic spacer around here somewhere I can use as a template. I've got to finish a motor for a Vettenet guy and I'll get on it right after that...Particularly if there's some interest!!
-Jeb

 

I'll post to the zr1.net to see who else might be interested

 

Cool...And I'll update you on my findings...
-Jeb Burnett

 

Jeb,

I would be very interested in a plate-type kit that fits between the injector housings and the plenum. Please keep me posted, as I am getting ready to buy a nitrous kit soon and this sounds like the best possible alternative. Thanks.

Mike