waasssupp.
im turnin my beater CRX HF into a v8 killer.
im going N/a building a GSR engine up for all motor and nitruos.
the setup:
JE 12.5:1 pistons
eagle H rods
bored over/resleaved to 86mm (2.0 liters)
blue printed and balanced
crower valves & springs, Ti retainers
crower stage 3 road rally and strip cams
adjustable cam gears
Fool rail
STR manifold
70mm STR TB port matched to mani
ported head
full MSD ingnition
9000rpm redline (variable after i take it to the dyno)
--all other required fuel managment upgrades fuel pump, VAFC obD0-OBD1 conv with reprogramed p28, EGT gauge, WB o2, bigger injectors, ETC.
The question is,,.
Im going to run a Nitruos Oxide Systems direct port kit ( i hate using the word/letters "NOS" anywhere) anyhow. i was thinking in the area of a 120 shot that would come in only under full throttle and above 4000Rpms. ive heard of people running a 120 shot (wet fogger) on a stock GSR engine, not many times, but it has been done none the less. So i know my engine can take it but, it will be more precise with direct port and more power. Does anyone have any input on my setup? does anyone think it may be too much for the engine? The nitruos will only be used for special occasions, like only a few times at the track so i know what it will do, and of course on money races. Any reliability issues? thanks to all that help me out and give me advice.
-james

 

i may be way off course here but you will have to think about your compression ratio...what type of fuel you are planning to use and i would definately go with an aftermarket ignition system... but it sounds like with your setup you may be able to handle a 120 shot...im too much of a punk to try anything that drastic on my daily driver...good luck..

 

Nitruos and compression ratio dont efftect each other. 120shot on 8:1 or 15:1 doesnt matter, its going to do the same thing. like, you dont have to use less on a high CR engine. and you can use more on a lower CR engine. the only real differnce is tuning, tuning will be harder at higher CR's and of course youll have more power at a higher CR. yes im going with a after market ignition system. Anyone else have any info? thanks
-james


[Modified by JDM CRX, 7:30 PM 2/24/2003]

 

I won't deny that there is no certain CR to run with Nitrous, but a high CR will have a far greater chance of detonation. To run a 120 shot, you might want to consider race gas or some sort of octane booster like the one available from nitrous express. Going with the upgraded ignition, like you have choosen, is very important. Another thing is to make sure you run a colder spark plug.

 

yes, i will have colder plugs for when i spray. im leaning towards 11.5:1 CR ratio over 12.5:1 i cant think of what this process/technique/term is called but, im adding some material in between the valves on the head, this provides for better combustion becuase the gas is even more centrally placed in the cumbustion chamber. this also means less CC's in the head which of course means a higher CR. plus you have to mill it to smooth it out, (higher CR again) to where my 11.5:1 CR pistons will be higher than that and yet the 12.5:1's wont be much higer than that, which will be bad.
also with the extreme overlap with the cams, the CR ratio isnt always 11.5:1 when VTEC hits becuase of the overlap.(it will be less) On definate "spray days" ill dump some 110 or 115 in my car. ill buy a 55 gallon drum of it. otherwise on 11.5:1 CR i think 93 octane with proper tuning should suffice for all motor days.

 

Sounds like you got it all planned out pretty good. Good luck with it.

 

Im doing a B18C1 build right now, specs very similar to yours, 86mm bore, the works. Im gonna run 11:1 CR. Plan to run N/A for a while but later add direct port 160 shot.

 

The setup sound cool but I would definately run race gas if your going to sqeeze especially on that high compressio n motor