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454SS
06-12-2006, 09:47 AM
Hi, I have a 454SS truck that I occasionally run at WIR. I have just purchased a NOS big shot 200-400hp kit for it, but am unsure how much nitrous to spray.

My engine is a 496. The block is a stock 4-bolt block with arp main studs. Crank is a scat 4340 4.25 stroke. Rods are scat 4340 6.385". Pistons are JE/SRP 18 cc dome 4.310 bore. Heads are cast GM open chamber milled to 104cc. Cam is a crane with .580-.600 lift and 290*-300* solid lift. Team G intake and 1050 dominator. Msd distributor and 6A box. Coan 5500 stall convertor and Turbo 400 manual shift trans. 3.73 rear end. Compression ratio is 11.6-1. Fuel system is a aeromotive A1000 pump and bypass regulator with 10an feed and 8an return. 6an carb feed. What would be a safe level of nos for this engine without changing anything internally? Thanks in advance for any info.
1SLO5.0
06-12-2006, 09:59 AM
That depends on how loose the clearances are. I'm sure the parts will handle 300hp or more but if you have a tight ring gap, piston to wall clearance or piston to pin clearance you will run into trouble. Do you have the specs from when the engine was assembled?
T-Bagger
06-12-2006, 10:06 AM
i ran a 200 shot ALOT ALOT on a pretty much stock 327 and never had a problem and thats doubling the horse power
454SS
06-12-2006, 10:08 AM
That depends on how loose the clearances are. I'm sure the parts will handle 300hp or more but if you have a tight ring gap, piston to wall clearance or piston to pin clearance you will run into trouble. Do you have the specs from when the engine was assembled?


I assembled the engine myself, and the only spec I can remember is the ring end gap. I gapped the rings to nitrous specs because I had a feeling that I might want to spray it at some point.
Dave Bandt
10-28-2006, 10:58 PM
If you followed the ring manufacturer's directions for ring end gap for nitrous then your limiting factor should be your knowlege of tuning nitrous systems. The engine components you described should easily withstand a 400 shot. The question is, can you deliver that much without hurting parts? Start small and work up....reading the plugs as you go....and you should be fine.