additional retard for NOs

[suprabad]

Is there a rule of thumb for a turbocharged engine when calculating ignition timing retard for the addition of NOs?

The guys I know are all running n/a V8's.

My usual method is to blow-up whatever I am running to find it's limits. Hopeing to possibly avoid that.

:nono:

 

[MK3Brent]

For every 100 shot, retard I think 1-2 degrees?

I'll search it here in a second.

 

[IJ.]

I'd pull 5 degrees and possibly run it on a dyno using electric ears to listen for detonation before cranking any more advance in (sick of using the test to destruction technique as well)

 

[suprabad]

Information on this seems pretty hard to come by...it's like looking for sympathy at an Ayn Rand reading.:icon_bigg

 

[IJ.]

I'd PM one of the heavy hitters that tunes their own car and maybe they'll be friendly enough to point you in the right direction (don't count on it though)

As I said I'd start conservative and work up slowly from there listening for any sign of detonation (electric ears are amazing you'll be shocked at the racket our motors make)

 

[Slow66]

General rule of thumb is 2 degrees for ever 50 additional hp.

 

[suprabad]

...(electric ears are amazing you'll be shocked at the racket our motors make)

I have heard that...I'm ashamed to say that I've never used them. But I'm going to now.

I come from the "old school" (which was just called "school" when I was a kid:icon_razz ) and I don't think they even existed when I was coming up.

I am trying to keep it as simple as possible because I am a one-man show, I'm finding out over the course of the last 3 years or so, that if I want to run quickly (relatively) and consistantly, I gotta go high tech. Tough for an old v8dog to learn new tricks.

But I'm learning in spite of myself.

My local strip is holding a lot more 1/8 mile races this year and it's:

1. Adapt,
2. get used to losing
3 don't play.

That's why the NOs. I need some more go to move this beast off the line to be competitive in such a short contest. Also, I'm going dual stage, so I'm really treading in unfamiliar waters.

 

[suprabad]

General rule of thumb is 2 degrees for ever 50 additional hp.

That was a straightforward answer from a qualified source...Thank-you.

 

[KicknAsphlt]

I really don't think you would need to pull much timing, if any, since the nitrous acts as a cooling agent for the intake charge. Maybe switch to a 1-step or 2-step colder plug and maybe a couple degrees pulled....although, I will admit -- I've never played with nitrous personally on any of my vehicles....but I did stay in a Holiday Inn Express last night! :biglaugh:

 

[IJ.]

SB: I played around with it when I was a kid and had a ball...... till the bottle ran out

 

[Tun_x]

I read "retard" in the title and thought this was about me:biglaugh:

 

[Slow66]

Jason, if it was about you, it would be titled - "Additional retard with nitrous"

As for the general rule i previously posted, it errs on the side of caution for people who haven't used it or don't use it often. You could use less, but its always better to start conservative, as i'm sure you're aware

 

[Tun_x]

I am going to jump out on a limb and ask a really "retarded" Question .. What fuel are you planning in running with the nitrous? Let me clarify .. if you plan on running the nitrous only on small occasions like a visit to the local 1320" then I would compensate for the additional power and lower knock threshold with a higher octane fuel... C16... This method works for the average street car.... If you are playing with the big boys better put it on the dyno like IJ suggested .

 

[annoyingrob]

(electric ears are amazing you'll be shocked at the racket our motors make)

I have an amplifier permanently installed in my car to plug my headphones in, and listen to my knock sensors

 

[IJ.]

N2o while being a great power adder can turn into an instant full flush button if it's not set up correctly

Side note way back then (very early 80's) a bud had a kit on his 186ci I-6 domestic thing, he was wondering what would happen if he had the car in drive and punched the button with the motor idling

Sheared off both axles at the splines DOH!

 

[7thousandpiecesMGTE]

N2o while being a great power adder can turn into an instant full flush button if it's not set up correctly

Side note way back then (very early 80's) a bud had a kit on his 186ci I-6 domestic thing, he was wondering what would happen if he had the car in drive and punched the button with the motor idling

Sheared off both axles at the splines DOH!

cool......

 

[suprabad]

I am going to jump out on a limb and ask a really "retarded" Question .. What fuel are you planning in running with the nitrous? Let me clarify .. if you plan on running the nitrous only on small occasions like a visit to the local 1320" then I would compensate for the additional power and lower knock threshold with a higher octane fuel... C16... This method works for the average street car.... If you are playing with the big boys better put it on the dyno like IJ suggested .

It's not a "retarded" question (yeah I get it). In fact, I've already been giving it some thought because higher octane race fuel will give me a little buffer against detonation. This will be especially important since I will have to "retune" fairly often to suit what I'm doing at the time, since I actually drive the car (ok, not far and not everyday, but I do drive it).

And because it's not practical for me to put it on the dyno everytime I plan to "let the cat out of the bag" and take it to the track (if you haven't figured it out yet, it's a total sleeper) , I'll have to work up to (but hopefully not past) the limit.

As for the general rule i previously posted, it errs on the side of caution for people who haven't used it or don't use it often. You could use less, but its always better to start conservative, as i'm sure you're aware

I appreciate you (wisely) dispensing conservative (read that: less likely to grenade) advice and taking the time out to clarify. Thanks.:bigthumb:

 

[Tun_x]

Let us know how it turns out ..

P.S. most turbo cars love NITROUS

 

[suprarich]

Your limit on HP before pulling timing will also depend on how close you are to detonation before adding the nitrous.