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nitrous tune?

Posted By: MegaDart

nitrous tune? - 09/23/09 06:30 PM

if my fuel pressure problem is solved I plan to hit the new car with a 200hp shot for 2 secs. at sat. nite bracket race. It is 1/8mile and my best time on motor is 5.01
any guess as to what it will run on the NOS??
Posted By: challenger1320

Re: nitrous tune? - 09/23/09 06:39 PM

How soon are you turning it on? What system plate of fogger? What tune-up (jet numbers)?
Posted By: Triple Threat

Re: nitrous tune? - 09/23/09 07:19 PM

Depends on when you have it set to engage, its gonna make more of a difference if you're on the spray from the get go, rather than using it down track.
Posted By: MegaDart

Re: nitrous tune? - 09/23/09 08:05 PM

it is an NX plate system I will have to check my logbook but it is jetted for 200hp (41/62?). I am turning it on .01 out for 2 sec duration and will be pulling out 10deg of timing at the hit.
I feel this should be a very safe tune? Baby steps as it's been a long while since I played with NOS and I'm really not looking for huge gain.

Attached picture 5501106-dscn2456.JPG
Posted By: challenger1320

Re: nitrous tune? - 09/23/09 08:19 PM

Check the jetting something isn't right with those numbers if that is nos 41 / fuel 62 you are way way to fat. With a good tune-up, on at .1 for 2 sec should see around a .2 decrease in ET
Posted By: Quicktree

Re: nitrous tune? - 09/23/09 08:23 PM

and you haven't consulted with Monte why?
Posted By: MegaDart

Re: nitrous tune? - 09/23/09 08:24 PM

ok just checked 57nos 41 fuel, I will be running 8psi fuel pressure.

.2 is exactly what I would like to see in the 1/8. Then I can chase me a few dragsters!
Posted By: MegaDart

Re: nitrous tune? - 09/23/09 08:26 PM

Quote:

and you haven't consulted with Monte why?



because I just finished the install... actually it's not fully plumbed waiting for the big brown truck!!
Posted By: BobR

Re: nitrous tune? - 09/23/09 08:27 PM

Quote:

it is an NX plate system I will have to check my logbook but it is jetted for 200hp (41/62?). I am turning it on .01 out for 2 sec duration and will be pulling out 10deg of timing at the hit.
I feel this should be a very safe tune? Baby steps as it's been a long while since I played with NOS and I'm really not looking for huge gain.



Why 2 seconds? Seems a smaller shot for the entire run would be easier on things.
Posted By: MegaDart

Re: nitrous tune? - 09/23/09 08:39 PM

Quote:

Why 2 seconds? Seems a smaller shot for the entire run would be easier on things.



I gotta start somewhere don't I? Looking for data and to stay very conservative. There is a method to my madness and an objective. That is to be dialed 7.50 in Rockingham next month with a little NOS as possible.

also, it is sat. nite bracket race and I will be lucky if the track will hold what I've got
advertised tuneups are usually pretty safe also to it may be more like 150hp. IMO, any less would be a waste of time.
Posted By: challenger1320

Re: nitrous tune? - 09/23/09 08:58 PM

Personaly I am with Bob on this I would spray a 125 shot from as close to 0 as possible and spray the whole run. I have a 73 Challenger at 3100 LBS with a 572 -1 motor in it runs 5.50's in the 1/8 with a 125 shot spraying from 0. 1.21 60 foots
Posted By: MegaDart

Re: nitrous tune? - 09/23/09 10:05 PM

what's it run off the bottle?

it's funny, I never thought of a 200hp shot as being very large
Posted By: challenger1320

Re: nitrous tune? - 09/23/09 10:18 PM

5.80's
Posted By: 602heavy

Re: nitrous tune? - 09/23/09 10:35 PM

I run the NX perimeter plate like the one you have , maybe set the FP @ 9 PSI , 10* is a good starting point , what fuel are you using? , these are great kits with a good jet spread out the box , i agree , hit it straight off the line.
Posted By: MegaDart

Re: nitrous tune? - 09/23/09 11:28 PM

maximal

I'll stick with .01 off the line for now, at least for the first hit! will aid in the learning curve!!
Posted By: racerx

Re: nitrous tune? - 09/24/09 01:55 PM

Quote:

Personaly I am with Bob on this I would spray a 125 shot from as close to 0 as possible and spray the whole run. I have a 73 Challenger at 3100 LBS with a 572 -1 motor in it runs 5.50's in the 1/8 with a 125 shot spraying from 0. 1.21 60 foots

challenger1320 what type of chassis u running/rear end.Thax
Posted By: challenger1320

Re: nitrous tune? - 09/24/09 02:00 PM

Basic backhalved car with mild steel 8 point cage. Dana 60 with 4.10, 33/16.5 x 15 Goodyears
Posted By: emarine01

Re: nitrous tune? - 09/24/09 02:47 PM

I allways looked at it from the torque gain not the hp , 200 shot down low makes for a lot of twist
Posted By: BobR

Re: nitrous tune? - 09/24/09 04:49 PM

Quote:

maximal

I'll stick with .01 off the line for now, at least for the first hit! will aid in the learning curve!!



.01 off the brake is functionally the same as off of the brake. The .01 just gets the tires loaded before the unit hits. The part that I don't understand is why you would want to turn it off before the finish line.
Posted By: MegaDart

Re: nitrous tune? - 09/24/09 05:35 PM

Quote:

The part that I don't understand is why you would want to turn it off before the finish line.



because I really don't like nitruous I just need to find .2 et. Looking to shut it off asap...

I would like to know why you and challenger think it is better to spray the entire run rather then the way I plan to do it?? I know quite a few guys that do it this way.
Posted By: Clockwork

Re: nitrous tune? - 09/24/09 06:20 PM

Quote:

if my fuel pressure problem is solved I plan to hit the new car with a 200hp shot for 2 secs. at sat. nite bracket race. It is 1/8mile and my best time on motor is 5.01
any guess as to what it will run on the NOS??



We just hit mine with a 175hp shot .3 in for the entire 660' and gained .3 but iv got the wrong converter so im sure theres way more.
So if your converter can take it???

Good luck
Posted By: challenger1320

Re: nitrous tune? - 09/24/09 07:02 PM

I like the smaller shot because of cylinder pressure and less strain on the drivetrain. The 125 shot for the intire run will net about the same as a 200 shot for 2 seconds. Plus the MPH will be up.
Posted By: MegaDart

Re: nitrous tune? - 09/24/09 08:18 PM

thanks clock, you bring up a very good point. The convertor. Yet another reason why this testing will be critical. This convertor stalled 6700 on motor but Abruzzi said it would be fine for nitrous. I'm guessing a tad loose another reason for a baby shot!! no worries about the drivetrain as this is a promod car with a bracket motor in it!! cylinder pressure also something to consider, thanks!
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