adding N/O to a 15.33 to1 engine

Old 10-30-2009, 08:03 PM
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andybyrd
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Default adding N/O to a 15.33 to1 engine

can I put a 150 shot of N/O to my 434 @ 15 to 1 -660 h/p with out damaging it and what kind of life will it take out of its life cycle in other words how much longer would just running gas last vs running N/O. I just want to go from 6.10 to 5.80 in the 1/8 without tearing up my motor
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Old 10-30-2009, 09:38 PM
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hammertime
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150hp is pretty safe , but make sure you have the timing retarded 6 degrees and adjust the fuel accordingly.
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Old 10-31-2009, 07:01 AM
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TheRabbit
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Originally Posted by hammertime
150hp is pretty safe , but make sure you have the timing retarded 6 degrees and adjust the fuel accordingly.
Also remember that a 150shot isn't much added horse power. Don't forget you loose about 10hp per degree of timmig you take out to run the NOS.
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Old 10-31-2009, 09:55 AM
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andybyrd
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Ok, so I take 60 hp out of a 660 hp motor makes 600 then add 150 would make it now 750 w n/o so it will be like adding 90 h/p, I just wanted to make sure It did'nt blow the rings out. I've been told that for every 100 hp of n/o is raising your compression up 1 point. like mine now is 15.33 to 1 then with the 150 shot of n/o it would be 17 to 1 is this true.
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Old 10-31-2009, 03:09 PM
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hammertime
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Originally Posted by TheRabbit
Originally Posted by hammertime
150hp is pretty safe , but make sure you have the timing retarded 6 degrees and adjust the fuel accordingly.
Also remember that a 150shot isn't much added horse power. Don't forget you loose about 10hp per degree of timmig you take out to run the NOS.
I've never seen the 10hp per degree on mine, I think this is dependent on the combo and all my vary. My 150hp picks up .15 for 2 seconds but I pull 6 degrees and am wayyy safe on fuel pressure with a seperate system. Also normally the faster you hit it the faster it'll be
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Old 11-02-2009, 09:58 PM
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russ67chevelle
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i dont believe that 10 degree stuff earlier posted...
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Old 11-03-2009, 10:21 AM
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Sorry guys if you don't believe it. Ask your engine builder.
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Old 11-03-2009, 04:44 PM
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hammertime
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Originally Posted by TheRabbit
Sorry guys if you don't believe it. Ask your engine builder.
I've actually done better, changed the timing on the dyno 1degree isnt 10hp maybe 3-4 degrees but again every motor is different 10hp is a stretch
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Old 11-03-2009, 06:55 PM
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fastguy1
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i sprayed my 588 with a 500 shot speed tech fogger and picked up 350 hp worth of et. 5.17 on motor, 4.55 on spray at 2300lbs
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Old 11-04-2009, 08:49 AM
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There is a lot of "not so trues" in this post.

(1) 150hp as far as what is recomended as a baseline tuneup for the nitrous manufacturer will not net the same horsepower gain from one engine to the next, so a 150 shot on a 10.5-1 350ci will not net as much horsepower as a 150 shot on a 15.5-1 632, both tuned accordingly. There is not one nitrous system manufacturer out there who can recomend a tuneup that will be perfect out of the box. The only way to give a nitrous engine what it wants or needs is the ability to read spark plugs and make the proper adjustments to get the mixture right (nitrous fuel ratio) and ignited at the proper time (heat mark on ground strap of spark plug)

(2) Retarding the timing does not reduce the horsepower by 10hp per degree, at least not while the nitrous is in use. Retarding the timing allows the mixture to ignite at the proper time so that it doesnt detonate or pre ignite, which causes serious harm to an engine.

(3) Just to say to pull 6 degrees of timing for a 150 shot is wrong also, one needs to know what the initial timing on the particular engine being tuned is first, then there is the question of what the valve angle is on the heads, type of fuel being used, compression ratio, cam info....etc.
A properly tuned nitrous engine will leave a clean plug with the timing mark just around the bend on the ground strap of the plug.

In my particular engine when I go down the track with both foggers blazing, my timing is pulled down to 8 degrees. :shock:


Not trying to step on anyones toes here, just wanting to share some of the things that really matter when tuning a nitrous engine.
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