WTKA.... Want To Know About...heh.

Well, for most of my life, I have not used or been a large proponent of nitrous. I am one of those people that just has never liked it. However, due to circumstances beyond my control... I may end up running it on my car in the future.

I have always been under the school of thought that nitrous is fine for the motor regarless of compression (granted the engine can take it). Although I know it is a form of FI, I simply assumed that it would simply enhance the performance of a naturally aspirated car, regarless of CR. But recently, a friend told me that he thought my CR was a bit high for nitrous... I found this a bit perplexing, so just wondering about my future plans.

My question is: Is there a compression limit as to when you cannot use nitrous, or where the size of the shot will be severly restricted ?

Engine mods:
Sleeved block, forged internals 11.5:1 CR, 91 to 93oct pump gas, stock head. Intended shot: 50 Max shot: 75.

 

I think you will be fine.

 

50-75 shot will be cake on that C/R. I know of a few running more than that. If you go bigger than a 100 shot some race fuel and good tuning may be needed.

 

Coo... won't be going over a 75 shot... not on my street car.... regardless of my build.

 

Experiment with different ranges of cold plugs and different amounts of ignition timing. Personally I'd start out by adding a bit of unleaded race fuel to your 93 octane while you are figuring out the right combo. Tune the fuel jet for a 12-13:1 AF.

 

you want a two step colder plug

 

2 steps colder !? For that low of a shot... or because of the higher CR ? Will that have any affect on my off spray performance ?

 

The shot may be low but you're starting with a static CR of 11.5:1, so when the added O2 is released in the chamber coupled with your already high compression, I'd imagine the heat in there would skyrocket under the right cirumstances.

Like laughin said, tune it for mid 12's A/F with an AFC to polish it up and I'd run the 2-step colder plugs with a small gap.

 

You mite wanna pull back some timing when you spray to be on the safe side.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by swlabhot &raquo;</TD></TR><TR><TD CLASS="quote">You mite wanna pull back some timing when you spray to be on the safe side.</TD></TR></TABLE>

Mmmm...yeah... I'm still trying to decided on how I'm gunna do that... I might just go w/ Hondata at that point... but still undecided.

But again... will colder plugs affect off spray performance ?

 

you'll be fine on the colder plugs for all motor, i had a lsvtec with 11.5:1 je pistons and shotpeened rods. ran a 120 shot. ran like a raped ape. don't worry bout it its not goin to affect you when your not on the bottle.

 

kewl...thanks for the assurance...

 

sorry to go a little off topic but...I thought I would start it in here instead of a new thing on me if im thinking dumb.

my car burns a little oil due to my rings when my friend built the motor. Would it still be safe for me to run a 75 shot.

I have a block gaurd, hondata, crower rods and je pistons 11.5:1 would this be a problem or should it be find.

thanks

 

actually... motors built for nitrous have pretty loose tolerences compared to straight N/A motors... just do a compression test to ensure you're holding decent compression first... and a leak down as well.

 

we have skunk stage 3's..12:5 compression pistons..and stock sleevs with a 175 shot on our nitrous car..runs fine..been runnin for a long time

 

ok thanks...I just wanted to check to see if that would be alright...but It would be nice if I could get some more opinions

thanks