Old Aug 6, 2007 | 03:37 PM
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Suicidal Racing
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Default figuring compression height and comp will

give u a damn head ache thats for sure..damn man damn..

i just went threw this seeing how i'm finally going to build another engine..been awhile since i did one..

but to keep cost down i wanted to use an off the shelf n2o piston vs having to pay $1000.00 or more for a custom set with 2 spares.

i'm going with an odd stroke..3.27 and a bore of 4.030..but i had to figure out what rod length to go with to be able to use a std 350 n2o piston..3.48 stroke with a 6" rod.

shit was a pain in my ass trying to see if i could use a flat top or a slight dome..i didn't want to go more then 12.5-1 in compression on this engine but wanted to stay above 12-1 seeing she will have a .700 lift cam.plus i had to leave enough room to keep the ring stack down in a good spot so i can hit it with a 250 or 300 shot of juice.

after looking at rod ratio's and rod sizes i finally came up with what rod i could use with an off the shelf je n2o 10cc dome piston..only took me like 3 days to figure out.

i'm going with this piston from je

part # --bore---stroke----rod----deck height ---comp height--compression
173583 -4.030---3.500----6.000----9.000----------1.25------12.6


my stuff will be

4.030 bore, 3.27 billet crank,6.125 rods,9.025 deck height.by using the 9.025 deck height it will put my piston down bore .015 and should bring my compression down to 12-1 depending on the gasket thickness.



if u guys are new to n2o u dont want your comp height less then 1.15 tops when u are going to spray the engine with i decent size shot.the more comp height will let u run a better ring stack for the n2o.

right now i feel like this but once done i will be like then when i spray her i'll be
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Last edited by Suicidal Racing; Aug 6, 2007 at 03:40 PM.
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