educate me please, what is needed for a 150 shot vs. a 300 shot?
i'd love to do a big shot of NOS but don't know enough about it yet to know what all i'll need to be able to do it. my motor can handle the big shot (see sig for mod list) but i don't know if my pocket can right now.
some of the kits i've seen say they require a aftermarket fuel pump and some don't... how about a nitrous controller, and maybe a MSD ignition system? what kind of stuff would be considered absolutely necessary and what can i do without, or optional? two stage vs. single stage... what are the benefits?
Re: educate me please, what is needed for a 150 shot vs. a 300 shot? (SonnyinVA)
Let me just say you've got one helova motor there. The big difference between the 150 and the 300 shot is how it is delivered. The 150 shot you can get a fogger kit with all the goodies for $1k You can even stretch that kit to deliver 200 or 250hp. The 300 shot requires a direct port injection, 8 foggers, 1 per cylender tapped into the intake manifold by the injectors. This requires more machine work and more parts. Pretty much double the cost of the fogger system.
Depending on your shot and your current set up you may need a new fuel pump for the extra horsepower and and MSD to retard the timing a bit.
Re: educate me please, what is needed for a 150 shot vs. a 300 shot? (mn_vette)
well, i've been saying 300 cuz i was checking out the Holley NOSzle kit. it says it supports up to 300 and appears to be a good/easy alternative to hard line plumbing and drilling/tapping a traditional direct port setup.
i just don't really have a good appreciation for how big i could go without a new fuel system etc. if i understand it right, the wet systems have a solenoid that controls the fuel pressure and so you can get away with a bigger shot with one of these on a stock fuel pump??
i just don't want to overbuild and as a result... overspend. haha. thanks!
Re: educate me please, what is needed for a 150 shot vs. a 300 shot? (SonnyinVA)
definatly go with a wet system, otherwise you're gonna need some darn big injectors to make up for a 300 shot. The wet system has a solenoid that controls the flow of fuel, not the pressure, and it's either on or off. The amount of fuel is determined by the 'jet' that you put in the outlet nossle.
What kind of fuel pump do you have now? If it's the stock pump you are probably getting close to maxing it out already. Some people do a dual pump, or an aeromotive, or a walbro with a boostapump. I've got a dual walbro setup in mine, total cost about $400. $225 for the pumps and an extra $100-150 for the extra feed line and filter. But it should hold 1000hp
Re: educate me please, what is needed for a 150 shot vs. a 300 shot? (mn_vette)
Sonny,
There's A LOT of difference between a 150 hit and a 300... And most of it has to do with the internals of your engine. I know you had a killer engine built but with the amount of stroke you're running I would wager your pistons' compression height is about 1", which is too little for a 300 shot. A 250 hit would be okay but a 300 would be seriously pushing it. Whenever you get above 250 (really 200), you need pistons with a dropped top ring land to fend off the cylinder pressure spikes without fluttering the rings. That generally requires at least an addition .125 of compression height (like 1.125" vs. 1.00") or more. My nitrous pistons in my 396 had the ring lands dropped .200" over a stock performance piston. Once that's been done you'll need to have the rings file fit for a big nitrous hit, they require a larger ring gap than n/a operation because of the cylinder pressure. With the amount of cylinder pressure developed by N2O it pushes the rings together and if the gaps aren't wide enough it can cause them to butt ends and "flutter" which will typically break the top ring land and shortly thereafter destroy the cylinder. Typically .005" to .007" per inch of cylinder bore is what is needed for nitrous use up to 300-350 hp...
-Jeb
Re: educate me please, what is needed for a 150 shot vs. a 300 shot? (jburnett)
it's little things like this that make me glad I had professional help building my engine I remember by builder saying something like that when I told him I wanted to run a big nitrous shot
Re: educate me please, what is needed for a 150 shot vs. a 300 shot? (SonnyinVA)
Sonny,
You run a very similar long block as to what I run in my street car. 4" stroke, I'm assuming a 0.040 overbore, 5.875" Oliver billets, JE customs with reverse dome, same set-up.
The only real difference is that I left the SPEC stage III on the ground at 6300 RPM at the top of 2nd gear. Beware!
I now run a McLeod twin disk on the aluminum flywheel. All seems in order now.
Corvette Store
educate me please, what is needed for a 150 shot vs. a 300 shot?
I remember by builder saying something like that when I told him I wanted to run a big nitrous shot 
