ok so heres the deal right now im running a b18a1 bored to 81.50mm, wiesco 11.5:1 pistons, eagle h beam rods, and golden eagle block guard. i have a built ls head done by exospeed racing. port and polished,supertech valvesprings and retainers, supertech stainless steel valves, brian crower stage 2 cams, blox intake manifold, blox 70mm tb, 310cc injectors, and was running on 100shot dry single nozzle. car went 11.91 @116mph on 22" slicks. i plan on pulling ls head off and going vtec. i have purchased i built gsr head port and polished, rocket motorsports springs and retainers, rocket motorsports m24x cams, omni flat faced valves, and twm itbs. i also purchased a zex direct port nitrous kit. the motor will have right around 12.5:1 compression maybe a little more. i want to know how big of a shot can i run on it. i will be using 116 octane gas. everyone is telling me 150 shot. i need some opinons from people who have done it.

 

I run a 100 shot on my ls and thats 9.2:1 compression at 12.5:1 yes you would need to run 116 octane and direct port and pull like 8 to 10 degrees of timing

 

I would ditch the zex kit for starters. Whats your fuel system ?

 

That motor will go like stink!!. ? how did you arrive at that compression ratio, you would have to know how much was taken off your head and block when it was re-surfaced + cc the chambers and some other math ?'s come to mind.
Not getting down on you just curious, anyway if you weld the block guard in and took the time to polish the pistons and combustion chambers you still need a dedicated fuel system to run that much nitrous or bigger injectors and a bit of ECU work. If you use a stock OBD 1 ecu your car goes "open loop" and its easier just to add the fuel through the nozzles.
I would get rid of the Zex kit and get nos 04430, I had great luck with it but the 160shot is a handful, my motor is built quite like yours but its a Z6. I got 1.7 60's and 106mph in the 1/4 12.4 best. I feel my 23 8.5 15 slick are too small and keeping the head gasket on is proving to be a challenge,I'm getting the Block guard tig welded in before my next time out.
I can't tell you what kind of timing to run because I have not seen your pistons or chambers but I can tell you with a hell of alot of polishing to those parts I was able to get 11 degree before things started to melt on a 160 shot w/ racing gas. hope it helps I could blabber for hours about this...

 

fuel system is 255 fuel pump, zex booster pump when nitrous is activated, and 310 injectors. i ran 100 shot dry without the booster pump tuned on neptune and had no problems but the head gasket. the motor spun a rod bearing 3 weekends ago, and tore the crank and number 3 rod and piston up. im rebuilding it now, but going with the eagle 95mm stroker kit. 10.7:1 pistons, with eagle h-beam rods. is the stroker kit going to be safe with nitrous? also not going vtec anymore staying with the ls non-vtec.

 

I type too slow for this website....if you can spray 150 with your current ecu and injector mods, do it, sounds like your having problems with 100 though.
I have a 255 no booster pump and I'm running lean, I can't modify injector pulse though, anyway I don't know anything about the kit and ecu you got.
If you weight match your pistons and rods then spin balance your whole rotating assembly maybe you can counter-act all the bad things I read about stroker kitsLOL.
vtec is traction control control for people that can't afford upgraded ecu's like myself....

 

you should do the same build w/ stock crank and bore it .25mm MORE, thick head gaskets are a real bad idea, so is a un-square bore and stroke. Go OBD1 if you like nitrous and get 04430.

 

will this setup be ok to spray a 75 shot dry zex?

ls block
ls crank
ls rods
jdm itr pistons
jdm itr head (stock)
compression is 12.5:1
block has 207 miles on it.
s300

 

Dont ruin your engine by running nitrous. i say build the vtec head and run a turbo.

 

WHAT THE HELL IS NITROUS.....i have herd of it but never seen it in action.


hman

 

trouble is back lol