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Why a somewhat lower stall is recommended for nitrous?

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Old 09-19-2009, 08:48 AM
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Default Why a somewhat lower stall is recommended for nitrous?

First my car is about 98% drag racing only. I am about to get a TH350 and was thinking about a 4000 or 4400 stall but have read several times that if you plan on using nitrous go lower on the stall. Can someone explain why? Thanks.
Old 09-19-2009, 11:36 AM
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In my personal experience, a 150 shot has made a converter in a past car flash much higher, like another 1000 rpms or more. So that car went 1.48 on motor, and 1.38 on a 150 shot.

Eventually nitrous will make a too-big converter flare so high that you (a) can't hook it or (b) launch too high in your powerband, and (c) the engine will stay too high in your power band during the whole pass.
Old 09-19-2009, 09:11 PM
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.

The more power you make, the more it will stall.
Same as a stock SBC will stall at 2000 and a killer BBC will stall at 6000 with the same converter.
You want the stall to match your combination. In my cars, I have 2 converters, one for N/A & 1 for N2O.
They both stall ~the same when used on what they were built for,
but will stall more or less if you try using them in a different combination.

When people say you need a tighter converter, they are talking about using a N2O converter N/A.
It's how you can buy a non-custom unit and judge how it may work on a N2O combination.

.
Old 09-19-2009, 09:41 PM
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I think it depends where you want it to flash on the jug. Motor won't matter if you are turning it into a nitrous car. My PTC stalls to about4200-4300 on motor, then 5500 on spray. That's right where I want it for nitrous. That's why you always hear nitrous guys talk about how their cars are dogs on motor.
Old 09-20-2009, 11:23 PM
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Mine is a 4200 na and 5g on spray. Is a dog on the NA side. chance stall




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