Ignition Timing and Nitrous Oxide

[rich s]

I have begun contemplating the addition of Nitrous Oxide to my engine for drag racing. (BGE block with forged stroker crank, rods and pistons and 9.5:1 compression)

Is there a way to set up a tune so that when nitrous is activated, the appropriate amount of timing is pulled, but equally, if nitrous is not activated, ignition timing remains unchanged?

Or is it a proposition where if you don't activate the nitrous, you have to live with retarded timing that would support nitrous if it was activiated?

Thanks for any insight.

rich

[LilSick]

convert it to corn

tune it for your 9.5 to one/cam combination

leave the timing where ever it ends up

and squeeze the snot outta it


how big of a motor, why 9.5, and what cam did you pick for that?

how big of a unit are you thinking?

[edcmat-l1]

How big of a shot, that should be the first question.

For the most part, you'll never notice the missing HP with the timing pulled for N2O when you're not spraying.

[LilSick]

How big of a shot, that should be the first question.

9.5 to 1

i am picturing 430-440 inches

leave on a 200 shot and ramp in an additional 250?

[Spray-Cam Hell-Ram]

Leave on a 200 shot? Might want to edit that post to swap out "Leave" for "Launch", and to put in a big, fat "Attempt at your own Risk" disclaimer in there along with it. But in any event, this suggestion has certainly caught my attention. And assuming Rich s or I wanted to run a shot combo like this, how would you suggest tuning the fueling to be able to leave on a 200 shot?

[rich s]

pistons available were 9.5:1 and 12.x:1. My builder (Jeff Taylor) said go with 9.5:1 as the engine is supercharged.

The displacement is 426

The cam is the Comp Cams Supercharger Stage 2 cam. 235deg @.050 lift, .625 lift.

[rich s]

How big of a shot, that should be the first question.

For the most part, you'll never notice the missing HP with the timing pulled for N2O when you're not spraying.

150 shot

[LilSick]

that is barely over 10% of what the motor makes

build a dry shot and write a tune for it

it will be a lil fat when not squeezing - no biggie

[LilSick]

Leave on a 200 shot? Might want to edit that post to swap out "Leave" for "Launch", and to put in a big, fat "Attempt at your own Risk" disclaimer in there along with it. But in any event, this suggestion has certainly caught my attention. And assuming Rich s or I wanted to run a shot combo like this, how would you suggest tuning the fueling to be able to leave on a 200 shot?

what are you trying to say?

have thrown what equals a lot more than that at a 100 cu in 4 cyl suzuki motor

with great success i might add : )

set it up so both fuel solenoids are wide open at the hit

the small unit's nitrous solenoid is open as well

ramp in the big nitrous solenoid with a controller

[edcmat-l1]

pistons available were 9.5:1 and 12.x:1. My builder (Jeff Taylor) said go with 9.5:1 as the engine is supercharged.

The displacement is 426

The cam is the Comp Cams Supercharger Stage 2 cam. 235deg @.050 lift, .625 lift.

Sounds like Jeff Taylor is the guy you'd need to talk to. I know if you were thinking about spraying 150 shot on my supercharged engine that I built for you, I would want to know.

[unicornpower]

So I have run between 100-200 on a hellcat engine at 18lbs. Forged rods and pistons and OfCourse better valve springs and push rods. That combo was 8.20-8.50 1/4 mile in my 3500lb drag car. Over 300 passes (not all nitrous) with no issues at all and now after a refresh of rings and bearings that engine is in my daily hellcat that now runs a best of 9.19 on a 125 shot.

I don't ever switched tunes as its not worth the gain to me. That is Unless I cross the 150shot barrier. I run no NOS and up to 150 all on the same tune. Never an issue. Could it run slightly better off the bottle with more timing? probably but it still runs 9.50-.9.70 depending on weather so I am good with that.

[LilSick]

if you were thinking about spraying 150 shot on my supercharged engine that I built for you, I would want to know.

1) that is your ego : (

2) that is job security : )

i have two nitrous pro mods in my trailer that i tune. a 150 shot on a 420+ inch motor is next to nothing. i build nitrous systems and nitrous fuel systems. lemme know if you want help.

[Spray-Cam Hell-Ram]

There was no underlying meaning there in my post. The comment about adding a disclaimer when telling someone to squeeze a 200 shot off the line was suggested only because doing so would be going directly against what everyone of the nitrous manufacturers tell you to absolutely never do in all of their install instructions pdf downloads. And while I'm sure you'll be able to tell me why doing so would be just fine, but because this about what he should do on his build and not your own, hence why and only why I made the "add a disclaimer" suggestion. That being said, the rest of the post was quite literal and genuine. I myself have just very recently gotten to the point where I feel comfortable enough to make my own nitrous set-up active and unlike yourself, Im quite inexperienced in this particular area. Im also in the process of converting over to E85 and am trying to decide exactly what kind of shot would be optimal for my current build/set-up when having a shot capability that ranges between 100-400 shot from my nitrous express Holley Hi-Ram nitrous plate kit. Im running a 6.5L stroker (396) with a lil over 12 to 1 compression, fully forged of course, and as a starting point I have to assume that my range will likely be quite a bit less than the shot amount available due to my compression. However, I do have a Maximizer 4.5 second progressive controller to start incorporated in my nitrous set-up, as well as their electronic rpm window switch. My initial thought was to run maybe a 200 shot over a 4 second progression once hitting around 3600-3800 rpm on a 1/4-mile pass. I was actually unaware that squeezing a shot right off the line was even an option to be honest. Which is why I had asked you in my post how would you tune your fueling for something like that. Because if there is a way to safely run a shot right out of the gate as well during a pass, then I think that that initial shot off the line would be the biggest benefit of all with running nitrous. I was legit asking you how this could be tuned for and done.

[LilSick]

I have to assume that my range will likely be quite a bit less than the shot amount available due to my compression.

However, I do have a Maximizer 4.5 second progressive controller to start incorporated in my nitrous set-up,

My initial thought was to run maybe a 200 shot over a 4 second progression once hitting around 3600-3800 rpm

that whole "nitrous dont like compression" thing died when companies figured out how to make fuel bout 30 years ago

whats it leave like now with the 3600?

lets see a log

2016...

it has a hp75 in it?