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Discussion Starter · #1 ·
Thinking of sticking a small shot of nitrous on my 383. Carb motor. Rings have a stock gap in them but I think a 100-150 would be fine?

Looking a perimeter plate set up. Can anyone school me on what all is needed? I know they sell the kits, but I feel like there is more I should be getting?
 

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Ok first you want a progressive controller that spreads that out over 1.5 to 2 seconds this will protect your rings.

I would use a fuel pump with 2 regulatiors. One regulatior is just for driving then a second regulatior that is fed when a solenoid is opened allowing additional fuel to be injected.

Now even with all of this I would not run more then a 75 shot activated under full throttle in areas where I knew holding that skinny pedal down would not be a concern.
 

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With nitrous you have one or two good shots then its over until you refill.

This motor sounds like a mild street build. I would look at ways to have it flow better and bump the compression up a bit.

Good chance you can make 100hp that way and have it available all the time.
 

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150 is too much on .016" (stock) ring gaps IMO.

If your ring gaps are closer to .020, the 150 should be fine. It's a tough call for me, if the gaps are too tight, then you'll be the 1st to know.

Obviously, you're looking to make some go with this thing. It would not be a waste of time in the slightest to pull the motor and yank the pistons and open the gaps up to .025" and let it eat. It will cost a set of headgaskets, intake gaskets, oil and some topoff coolant.

Regarding the system to use, a progressive system is the way to go if you can afford it, but any old wet system from Nitrous Outlet, Nitrous Express, or whomever will get it done - just be sure you have enough fuel pump and know how to adjust the timing. Start out with 50, 100, then 150. If our tune is good, then you'll be peaking at a 250 shot before long. If your tune sucks, then you'll be in need of new parts soon.

p.s. - this is super easy and quick with EFI.
 

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"With nitrous you have one or two good shots then its over until you refill."

The number of shots you get per bottle is determined by three things:
-Capacity of the bottle
-HP level of the shot in use
-Length of time system is active per each use.

Typical 10 lb bottle, 100 Hp shot, using it to turn a 14.5 second car into a 13.2 second 1/4 mile you're on the shot for about 11 seconds per use....you'll get 9, maybe 10 shots before it will falter in the middle of a run(which doesn't hurt anything, you just go pig rich and slow down)

Same 10 lb bottle, 180 HP shot turning a 11.3 second car into a 10.20 car, your on the shot about the whole trip so 10 seconds....you'll get 5 shots a bottle, it will stutter trying to run a 6th shot.

I've got a cousin who gooses 200 hp on a dirt drags Jeep CJ-5....on top of a 1080 HP 588" BBC. it's only on something like 1.4 seconds per run since it is something like a 200' long track, maybe 300' IDK? other than it is short.....he can get something like 16 or 18 shots out of a 10 lb bottle.

At 75-100 hp you'll be safe with stock gap, and you don't need a fancy controller, it can just be a button control from either steering wheel, shifter knob, or WOT switch on the carb.
doesn't need to be a perimeter plate either, it won't be any advantage at all.

Nitrous Oxide Systems original "Powershot" fixed jet basic 4 barrel system was 125hp and intended to be just fine on stock V8 motors.

Nitrous Express is considered by most to be one of the better nitrous companies, let them advise you as to what accessories would be best for your application and your expectations.
 

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A few other things come to mind, a pressure gauge for your bottle, in case they don't come with one and also, a purge kit.
If you want consistency, both of those will be needed.
You might want to think about a blow down valve in case you plan to mount the bottle inside the drivers compartment.
I used a relay and a wide open throttle switch on my car.
 

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Discussion Starter · #8 · (Edited)
With nitrous you have one or two good shots then its over until you refill.

This motor sounds like a mild street build. I would look at ways to have it flow better and bump the compression up a bit.

Good chance you can make 100hp that way and have it available all the time.
Thank y’al for all the input. It really helps. I had no idea there was a WOT switch!

I wanted to keep the motor NA, solely just for reliability purposes, so gaining another 75-100 out of it would be awesome. It currently has some stock Promaxx 200cc heads. Compression is already 10.6:1 but it does have a .039 head gasket and a .010 deck height. I could do a .027 gasket and get the quench better/compression up a little. I think a really good carb tuner would do me wonders. It’s a decent tune but I know it’s not completely right.

I’ve asked this before but I’ll ask again, send the Promaxx heads off to be machined or just buy some better out of the box ones?
 

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You won't find 75-100+ hp from porting the ProMaxx heads, if that is what your asking.
Niitrous is the quickest, cheapest way to add the additional power....it just also requires pay-as-you-go because of bottle refills.

To get an additional 75-100 hp NA you would need to add compression, change cam pretty drastically, port the heads and intake.
 

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You won't find 75-100+ hp from porting the ProMaxx heads, if that is what your asking.
Niitrous is the quickest, cheapest way to add the additional power....it just also requires pay-as-you-go because of bottle refills.

To get an additional 75-100 hp NA you would need to add compression, change cam pretty drastically, port the heads and intake.
Before I play with nitrious again or turbocharge a LS I want to look (again) into Compressed Air supercharging.

Potentially you could have a NA mostly stock engine bay, high psi air compressior ran off a inverter sitting in the trunk, and then fill a scuba tank from 300 to 3300 psi before stuffing that charge into the intake.

One of those things that has been known for years just not many people use it.
Unlike a turbo at around 5% or belt driven supercharger at lets say 10% you are able to save that percentage of lost horsepower by using compressed air.

While slightly more complicated then nitrous the benifits are there to fill your bottle over and over in around 30 to 40 minutes. Once installed the system can be ran for 5 years before the tanks would need recertification.

Currently I dont know anyone selling a setup with a inverter, compressior, valves, controller, and such to stuff compressed air into a 5.3.

Till then you can get your kicks off nitrious.
 

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The basic piece you really need for a plate style system is a really good electric pump with a return line to not deadhead it. I mean you'll probably spend as much on the fuel pump and regulator plus their installation as you will on a plate system but if you don't, you're just kidding yourself. Additional fuel is key. A single regulator with dual outputs is good enough for a system up to 250 HP. I would start off jetted in the 75-125 HP range, reduce your current timing to 26 degrees and come down 2 steps cold on your current plug. Make a pass, kill it and pull the plugs, you're looking for any signs of torching anything - if good, increase timing 2-3 numbers and run it again. You want to rinse and repeat as long as the plugs look good and you're getting faster and quicker. Not sure if you're on the street or strip, but there's a couple of decent phone apps that can measure ET for you. Keep increasing the timing until you have a no gain situation or a plug looks bad - then back down two numbers and that's your tune. Upping the NOS at this point becomes the tricky part. With each 50 HP increase you make, you will want to back down a few numbers on timing and then work back up to it. And the real kicker is this - at some point you will find other limitations. That could be just about anything that makes the engine work - pistons, rings, rods, head gaskets - all sorts of fun stuff. If you're just beating on the strip and bustin' somebody's chops then that 125-150 mark is good. Doing this for fun and profits means you'll have to lean on it a bit and have a deeper wallet.
 

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Here is how I had my switch wired:

618291


You can buy the switch and bracket from a lot of vendors, just make sure its the correct bracket for your model carb.
 
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