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nitrous question

Posted By: hornetnut

nitrous question - 08/13/13 11:50 PM

i have an 11.1 440, eddy heads, ultradyne 582 lift 282 @ 050, 850 dp holley, 4.11 gears 2500 verter.. what do you think ill pick up with a 100 shot of nitrous?
Posted By: a493demon

Re: nitrous question - 08/13/13 11:57 PM

3th's
Posted By: D-50

Re: nitrous question - 08/14/13 12:46 AM

My Demon with a 15-1 360 and Hughes stage 2 ported stock heads and Hughes solid cam around .615 lift went from 7.20 to 6.47 in the 1/8 with severe traction problems. Picked up 11 mph. Had 47 nos/53 fuel jets in a cheater plate, supposed to have been 100 shot according to N.O.S.

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Posted By: a493demon

Re: nitrous question - 08/14/13 01:24 AM

Quote:

My Demon with a 15-1 360 and Hughes stage 2 ported stock heads and Hughes solid cam around .615 lift went from 7.20 to 6.47 in the 1/8 with severe traction problems. Picked up 11 mph. Had 47 nos/53 fuel jets in a cheater plate, supposed to have been 100 shot according to N.O.S.


is that jetting backward's ?
Posted By: D-50

Re: nitrous question - 08/14/13 02:05 AM

No, that is what I used.

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Posted By: a493demon

Re: nitrous question - 08/14/13 03:02 AM

every thing I have read always has a bigger NOS jet then the fuel jet.
Posted By: D-50

Re: nitrous question - 08/14/13 03:16 AM

I just looked on my instructions and it has 47 n2o jet and 53 fuel jet.I ran mine that way for about 8 years and never had any problems. I would pick up close to 8 tenths in the 1/8.

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Posted By: Biginchmopar

Re: nitrous question - 08/14/13 03:28 AM

NOS always jets a little fat. (SAFE!)

I agree 3-4 tenths
Posted By: RobX4406

Re: nitrous question - 08/14/13 03:48 AM

Quote:

I just looked on my instructions and it has 47 n2o jet and 53 fuel jet.I ran mine that way for about 8 years and never had any problems. I would pick up close to 8 tenths in the 1/8.




Insructions are WAY off for a decent jet package. That's not even a little fat, that's a LOT of FAT!!! Monte updated a lot of the NOS tunes and that looks like an old one. The 100 shot set up I use to start is 47N/40F. I run a minimum of 7 steps smaller on fuel than n2o to start and step on it from there. Some guys like Monte, IIRC, have stated to run 10 smaller.

Sniper/powershot/cheater, jet them all the same and the fuel jet should not be larger than the n2o jet. That's what Monte told me.

You guys are beating the ring lands to death with those fat tune ups.

There is a guy on another site using a super powershot IIRC, ran the stock 150 NOS jetting, 55/61 picked up .7-.8. Changed it to square 55/55, pulled timing, it's picked up close to 1.4 seconds and it's still fat! 13.3 to 11.91 and there likely still another 3-4 tenths in it.
Posted By: a493demon

Re: nitrous question - 08/14/13 03:55 AM

I think right now I have a 14 spread .
NOS bigger jet.
Posted By: an8sec70cuda

Re: nitrous question - 08/14/13 01:41 PM

The old tuneups used a bigger fuel jet than the nitrous. The new tuneups are squared. Much better, but still fat.
Posted By: Mr.Yuck

Re: nitrous question - 08/14/13 04:24 PM

Quote:

3th's




in the 8th? I'd think a 100 shot would be good for at least 5-7 tenths in the 1/4.
Posted By: Quicksilver440

Re: nitrous question - 08/14/13 04:39 PM

The more modern theory is that Fat is not safe....Fat kills ringlands.
Posted By: OUTLAWD

Re: nitrous question - 08/14/13 05:29 PM

i just hit my junk with a "100" shot. I reversed the recommended jetting to 53N/47F and the plugs looked pretty good, stayed conservative with timing.

How tall of a tire? will you run out of revs at the stripe?
Posted By: hornetnut

Re: nitrous question - 08/14/13 08:42 PM

it is 1/4 mile and i have 26x10 slicks.. im hoping for 1/2 sec drop.. i shift normally at 5500, and cross the stripe about the same..
Posted By: Von

Re: nitrous question - 08/14/13 08:43 PM

Quote:

The more modern theory is that Fat is not safe....Fat kills ringlands.




IMO, its not "theory", its fact.

Go to one of Monte's classes. He explains it in very good detail.
Posted By: RobX4406

Re: nitrous question - 08/14/13 08:56 PM

Quote:

it is 1/4 mile and i have 26x10 slicks.. im hoping for 1/2 sec drop.. i shift normally at 5500, and cross the stripe about the same..




What's it run now?

A 100 shot on a 13 second car will pick up ~1+ seconds, same shot on an 11.00 car, not so much.
Posted By: hornetnut

Re: nitrous question - 08/14/13 09:38 PM

11.60
Posted By: GTX MATT

Re: nitrous question - 08/14/13 10:18 PM

Not sure but I think you'll pick up more with a smaller cam or a lot more converter (5000+). What are you running for heads, intake, and exhaust?
Posted By: hornetnut

Re: nitrous question - 08/14/13 10:50 PM

i was told this verter was supposed to stall over 3500, but i can only get 2500 out of it, eddy perf rpm heads, perf rpm intake, long tube headers and 3 in exhaust
Posted By: MR_P_BODY

Re: nitrous question - 08/14/13 11:29 PM

Quote:

i was told this verter was supposed to stall over 3500, but i can only get 2500 out of it, eddy perf rpm heads, perf rpm intake, long tube headers and 3 in exhaust




Since NOS makes torque your conv WILL stall higher
and that in itself will help you... I've talked with
Monty on DW and he has always said the OLD specs were
WAY off... way too much fuel.. they USE to think that
was a safe way to go... NOPE
Posted By: D-50

Re: nitrous question - 08/15/13 12:06 AM

Well my Demon picked up almost 8 tenths in the 1/8 with the 47n/53f jets for 6-7 yrs and never had ring problems but I did not spray it every pass. I was using a 5500 8 in. convertor, 4.86 & 5.13 gears probably 3400 lbs, stock interior,bench seat. I wish I had run a smaller fuel jet I might have made a 5.99 pass if it hooked.
My goal is to run a 5.99 pass in my D-50 and it is faster on motor than the Demon was on NOS.

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Posted By: Leon441

Re: nitrous question - 08/15/13 12:33 AM

On a 100HP shot you are not going to kill ring lands no matter what you do with 440 CID. You could block off either jet and remove no timing and maybe not run so good but you are not going to hurt it. IMO

MONTE SAYS, you should read your post guys come on. Monte has done a lot for NOS and a lot with it. You guys argue back and fourth over what Monte told you in his class. Yes, a more favorable jetting would be 47N with 40 or less Fuel. Depending on your base timing you can pull 0-6 degrees for that tuneup and expect to pick up a second.

100HP is a very forgiving level of nitrous. NOS had terrible recommendations for tune years ago. 47N/53F and remove nothing or maybe 2 degrees of timing was the recommendation. The car runs bad. So you crank the timing up. Meanwhile your rings are taking a fuel bath. The fuel trapped in your tight second ring clearance is pushing the tight top ring up and with the added timing combusting early pushing the top ring even more. The top ring butt's from lack of clearance and finally can't go anywhere and breaks the top ring land. Fuel alone can cause ring land problems. But, it usually is a combination of problems. Too much timing can murder ring lands too. I had a lean and mean tune and lost a plug wire with a small dist. cap that crossed over to the next cylinder it murdered everything. The ring lands broke, the top ring junk, the piston dome fried as well as the combustion chamber. All due to a 90 degree early firing event. I invested in a large cap and paid a lot more attention to rotor phasing and never walked away from the car with the hood off again.

Leon
Posted By: hornetnut

Re: nitrous question - 08/19/13 03:10 AM

this old marvin miller kit i used was out of the 70's, ended up being a 75 shot, but it still picked up .5 sec and i only sprayed 1/2 track... im hooked....figure i'll settle in at a 150 shot.
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