is high humidity faster or slower? also how much does IAT effect power?
11-26-2002, 09:26 PM
#1
is high humidity faster or slower? also how much does IAT effect power? seems like if water injection helps a blown motor high humididy would be similar and also help.
set me strait, is dry air better or humid air?
i know cold air is better, is there a rule of thumb for how much power a certain temp drop will give you?
set me strait, is dry air better or humid air?
i know cold air is better, is there a rule of thumb for how much power a certain temp drop will give you?
11-27-2002, 09:05 AM
#2
Re: is high humidity faster or slower? also how much does IAT effect power? Since you have ls1 edit, why don't you just "zero out" the IAT timing adjustments? It's an easy way to ensure you don't lose timing when it's warm <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> But there are tother considerations when doing this.
11-27-2002, 03:32 PM
#3
Staging Lane
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Re: is high humidity faster or slower? also how much does IAT effect power? I think the water injection is just a substitute for octane, to a point, by cooling charge air temps. The Alky give you the advantage to advance more becuase of the higher octane rating.
Also, for every 10F drop is a 1-2% increase for NA and 3-5% increase for FI.
Also, for every 10F drop is a 1-2% increase for NA and 3-5% increase for FI.
11-28-2002, 12:14 AM
#4
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Re: is high humidity faster or slower? also how much does IAT effect power? dry air is better. With humid air it take more energy to vaporize the air. This cost you slight power. The point adding alky to the water is to add something that gives off some energy. If you spray water/alky without increasing timing you would probably loose power. So yes it take more energy (hp) to vaporize the water/alky but you gain it back by the ability to increase timing. If you dont have to use water/alky to make the power you want then dont.
Gary
<small>[ November 27, 2002, 12:17 PM: Message edited by: red ws6 99 ]</small>
Gary
<small>[ November 27, 2002, 12:17 PM: Message edited by: red ws6 99 ]</small>
11-28-2002, 12:57 AM
#5
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Re: is high humidity faster or slower? also how much does IAT effect power? I'm sure there's a very interesting scientific answer somewhere.
The main consideration is probably the added weight of the water within the air. This will create a lot more drag and slow down the airflow to the combustion chamber.
I think the water molecules will fit in between the oxygen molecules in the air (they are widely spaced) and so shouldn't reduce the oxygen available for combustion much in a NA engine.
Regardless of whether the water is as a gas or as tiny water droplets (100% humidity), it will expand when heated by the turbo more than dry air, which will then dilute the available oxygen in the charge.
It's the oxygen we need and anything that reduces it's density will reduce power.
% reductions for NA and FI engines I suspect will be the same.
I think.
Anyone else care to give their .02?
The main consideration is probably the added weight of the water within the air. This will create a lot more drag and slow down the airflow to the combustion chamber.
I think the water molecules will fit in between the oxygen molecules in the air (they are widely spaced) and so shouldn't reduce the oxygen available for combustion much in a NA engine.
Regardless of whether the water is as a gas or as tiny water droplets (100% humidity), it will expand when heated by the turbo more than dry air, which will then dilute the available oxygen in the charge.
It's the oxygen we need and anything that reduces it's density will reduce power.
% reductions for NA and FI engines I suspect will be the same.
I think.
Anyone else care to give their .02?
