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Many factors come into play on that Gary, but assuming we are building an "all out" nitrous motor, that will see in excess of 600hp for a small block or 800+ on a big block, I do have some numbers I shoot for. I don't like more than 13.5 or so on compression for any combo. Chad's 632 only has 12.2 and runs like a raped ape on the spray, but a little more would probably help it. The 738 is close to 14.1..............Quench is tricky, because the head comes into play, but on most small blocks I will want .080 at an absolute min, but prefer closer to .100. Most 600" or so big motors in the .100 range and our 738 has .140. More stroke, usually means you need more quench distance to make it happy. As far as camshafts go.......Billy said smaller, that is NOT the way I go. Most of the nitrous motors I do have absolute MONSTER camshafts in them. To use a lot of nitrous, you have to get it in and out of the motor, hence I do some big stuff. I have small block cams approaching an inch of lift and many BB cams over that by a good bit. LOTS of duration at .050 and wide LSA numbers. The CAMSHAFT is where 9 of 10 guys miss the setup on a nitrous motor

Monte




So want would it take with a small block? Matt

Camshafts are a big part of my business. I have probably had 50 ground this year alone. That said, I will be happy to GRIND you a cam, but if you want me to just spell out here that you need this, this and this, so that you can have one ground by someone else, sorry, I can't do that.

Can give you a few ideas though. Say you have a smallblock that you are basically putting a big block load of nitrous in. Same amount of nitrous, yet you have a smaller bore, a smaller port, smaller valves, smaller chamber, less swept volume, etc, etc, etc. So what parameters would you think you NEED in a cam? Basically we have to "trick" the motor into thinking it is bigger than it is. So we need BIG and LONG valve action to fill the cylinder. Also, small fast burn chambers are VERY aggressive, so to keep the motor from burning itself up with chamber heat, you have to open the exhaust valve VERY early to blow the cylinder down and get the heat out. But you can't open the intake late to do it. So that means wide LSA numbers. We might grind the intake on a 117 and the exhaust on a 122, which leaves us an LSA of 119.5. Overlap is also a concern, because too much hangs the valves open and blows the charge straight through the chamber.

The term "nitrous cam" is really a misnomer. There is no such thing, nor is there a such thing as a turbo cam, blower cam, or anything else. It is just the "proper" cam for the application and what you intend to do with it.

Monte