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Old 30th June 2008
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Originally Posted by aswracing View Post
Small shots of nitrous, say 50hp and less, for relatively short periods of time, like drag racing, don't really require a reduction in compression. Just make sure it's jetted rich enough and you take out some timing. There are ignitions available that will retard the timing when you're on the button.
alright good. now for a another ?, You would though still have to set ur ring gaps, for nitrous. how much % wise of horsepower would u lose while not on the juice? if im wrong please correct me, but isnt it like 3%.

What you're trading off with 15 degree versus 30 degree is squish area vs. dome height. To get enough squish area at 30 degrees to make a real good chamber, you have to raise the dome height a lot. Well, that tends to raise compression. So most of the time, we do 30 degree on race motors and 15 on street motors.

The caveat here is that many aftermarket heads have a fair bit more volume. And you're going for 11 to 11.5:1 anyway. So you may well be able to get a 30 degree in there at a streetable CR and with a good surface area. Depends on the heads.

xb heads

Personally, I would cut them at 15 and make the measurements and run the numbers and then decide.

Well nrhs is gonna have them soon. The only problem is i have 15 pistons already. so if its not gonna do much for me(curbin detenation) id rather stick to the 15's. but if theres a lot of gain. then ill have to.

That's an excellent cylinder, I've used them on multiple builds (Axtell sells the same casting, but they do the machine work and put their name on it). I'd run'em. If you were doing a full-on race motor then yeah, a full cast iron would be better. But that cylinder will work fine on a street bike.
Dan told me the same thing actually. i just wonder longevity.but both u and dan say go with them. that means i go with them.
great stuff aaron. with ur help this motor is gonna rip. oh and any preferred nitrous system.
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