So when my dad had his motor built he was never planning on running nitrous but then someone told him he could get away with a little bit and that was that. I just got done installing his nitrous system, purge, and setting it all up with a microswitch and a toggle to activate the nitrous and a push button for the purge. We'll be running a 100 shot activated by the wot microswitch as mentioned.

I've been reading all night that detonation will kill the hypereutectic pistons so from that stems a few questions.

What fuel pressure would be best suited to make sure we run just a tad bit rich? We have a Holley Blue fuel pump with a regulator of course.

What heat range spark plugs and brand are preferred? A guy told me NGK's and 2 heat ranges colder would do the trick but I'd like more than just one opinion.

Also, timing? I think ours is set at 36 right now. I don't know if my dad will have the money either, to get the thing dyno-tuned before he takes it to the track. If that is a really big deal, then I'll make sure we get it dyno-tuned if it has to come out of my pocket as well.

We're running 11:1 c/r with iron heads so they won't dissipate heat as well as the aluminum heads but we haven't really had any cooling problems to date. knock on wood! So with that high of c/r ratio, what octane level do you guys think we need to be running? Usually we put octane booster in and of course 92 premium gas also so it's a mixture of both. I imagine the day of, when he goes racing we'll definitely be getting some race fuel but I don't know what octane that is? lol

We're both rookies to the nitrous game so if I missed anything feel free to add any input. Thanks in advance!!

Are you running a wet system?? You also might want to think about a retard box or set the timing back a few degrees..

What nitrous kit are you going with?

Don't try to run it rich. Ignition timing is critical. Run the recommended jetting and pull extra timing. Pull 2 degrees for each 50HP of nitrous. If you pull more it won't hurt. Don't bother with octane boosters just run race gas with around 110 octane on the nitrous. Use NGK R5671A-8 (stock #4554) plugs. Make sure your fuel system can provide the specified pressure for your kit when the nitrous is activated. If you don't have a flow tool like this: http://www.summitracing.com/parts/EDL-76506/ you can put the plate in a bucket to check the pressure when the fuel solenoid is triggered. An MSD Digital 6 would be a good thing to use since it can pull your timing automatically when the nitrous is triggered.

I don't know the difference between a wet and dry system? lol...It's a plate kit with the nitrous and fuel solenoids near the carb. It's an Edelbrock performer kit with the 057 jets which ends up being a 100 shot from what the tech guy told me over the phone when I had to call. My dad traded his rear seats for his nitrous system to this guy who had or wanted white interior i don't remember which, in his nova so i guess it was a perfect swap?

Our Holley blue goes up to like 10 psi, but our fuel pressure gauge is near the carb and I just read yesterday that once up to operating temp, that gauge can read lower than what it actually is so it might be hard to get a good reading maybe?

I'd love to try and get some gauges, or what not but my dad is a little strapped for cash so I'm not sure how possible it is to get some of these things to make sure everything is right, on the motor, fuel and nitrous wise.

My dad has a Mallory Ignition box, with a built in rev limiter....We'll definitely have to pull 4 degrees timing it seems, maybe 5 to be safe? Thanks for the part # on the plugs too, I'll have to write that down. I made a page of notes on a flash card last night. lol I'm pretty sure he'll be running race gas the day of also...

A dry system only sprays nitrous and are used on fuel injected cars. The fuel injection adds the additional fuel required with the nitrous. A wet system sprays both nitrous and fuel.

If you are using a 1-1/8" diameter back mount liquid filled gauge for fuel pressure, take it off and toss it in the trash. A non-liquid filled gauge from like this will work fine: http://www.summitracing.com/parts/ATM-2172/ Don't forget you need to check the fuel pressure while it is flowing through the fuel jet you will use on the fuel side of your nitrous kit.

Yes, pull 5 degrees of timing on the 100 shot.

Okay, it is definitely a wet system then. lol. We are running one of those liquid filled gauges...

So, how do I go about checking fuel pressure with the fuel solenoid open? I actually already have both the nitrous and fuel solenoids installed, teflon paste and all that...Am I gonna have to work backwards for a moment and re-do it?


edit: also, does the motor have to be tuned with the exhaust off, at the time of tuning, if it's gonna be ran with open headers at the track? thanks again!

First thing you need to do is get rid of that liquid filled gauge. To set the flowing fuel pressure using the plate do the following:

1. Remove the plate if installed.
2. Temporarily wire the fuel solenoid so you can manually turn it on and off.
3. Install the fuel jet you will be using in the plate.
4. Connect your fuel system to the plate.
5. Put the plate in a bucket, preferably clean so you can dump the fuel back in the car.
6. Turn the fuel solenoid on.
7. Turn the fuel system on.
8. Adjust the fuel pressure while the fuel is flowing through the plate and into the bucket.

Nice. I can do that. I know the whole thing inside and out now so it's not impossible or anything! lol Thanks for the detailed instructions!

i wouldnt run it on bottle unless you race gas in it --that booster stuff aint worth a darn-2 deg per 50hp boost is correect--seperate pump and regulator for nos i prefer---7lbs on motor pump and 5.5 on nos pump-2 ranges colder on plugs NGK will not burn the electrode off--i run autolite and rather have electrode burn off than not -simply if there is too much timing or something a burnt electrode will not kill a motor --also do research on reading plugs after each run -reading the strap-and dont worry -i ran 383 w over 120 runs on nos 250 shot w/ hyper pistons and stock crank

Well the nitrous is strictly for the track so it would receive race gas only I'm sure. We're just running a fuel pump with the regulator that came with it, and I doubt my dad will put more money into it for a set up like yours but doesn't sound like a bad idea. What range are the plugs in the link in the previous post above? Why would you rather have the electrode burnt off as to it not burning off? I've done some research on reading the plugs and wrote down some notes earlier about what to look for as to where the mark is, what color, to determine too much timing or not enough, and if it needs more octane and all that fun stuff...Appreciate all the help though everyone! Still learning here.

everybody has there own view on this-but in my case-say you run lean or you forgot to turn back your timing far enough--on a autolite or good plug the strap will completely be ate up and melted away-a NGK wont which could put a perty good whole in a piston or skirt-i have run my timing on the raged edge before on a heads up race and come back and my #2 strap would completly gone with no damage to valves, cylinder, or anything--o yeah -on sbc w single plain intake -the #2 cyl. is your lean cyl-so never forget that one to chek(thats on nos only--dual plain is 3 and 6

That is very interesting. I actually like your idea, as my dad nor I have the money to rebuild the motor if something drastically goes wrong but if that cheap insurance to picking out a different spark plug would save us the hassle "in case" then it doesn't sound like a bad idea. I'll definitely bring that up tomorrow.

So when this happens, and the electrode of the spark plug burns off, what happens while you're racing? Does it start misfiring horribly and/or whatever else but still not cause a catastrophic failure like the detonation could? Or nothing until you checked your plugs and realized the electrode is toast and would need to put new ones in before the next race? lol....So carrying spares would be a good idea...?

You can burn the straps off of NGK plugs also. Regardless of the brand, if you are burning the straps you have to much timing and you are going to damage your engine.

Thanks. I'm definitely gonna make sure he has the timing more on the safe side.

If you can't afford to replace it, you might want to hold off or limit the nitrous use. Do you have any ideas what the ring gaps are in that engine? hypers do not like tight ring gaps and if they are not set correctly the top of your pistons are going to get lifted off.

Steve, knows his stuff and has been playing with nitrous for a long time. I would follow his lead. I'm not saying Darrell doesn't know his stuff. The best thing to do is figure out who you want to listen to and do what they suggest. You can't take a little info from here and little from there and mix the two, often times that results in a bad ending.