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veil_side_
10-09-2002, 02:25 PM
First of all when running boost is the correct air fuel ratio 14.7:1?  I read somewhere (the book fails me) that when running boost it should be somewhere in the vicinity of 12:1?  Is that running lean or can anyone help me on this.  My second question is about .60 trim T3/T4 too small for the KA?  I'm looking for somewhere around the mid range high end part.  Don't know about this.  And what is the commonly used size for an intercooler on a KA?  I'm looking at something around 7inx19inx2.5in for my S13.

Jeff240sx
10-09-2002, 02:57 PM
14.7:1 is nominal for NA cars, but yes, when you run boost, or N2O, you want to run richer.  12:1 is 12 parts air / 1 part fuel.  12/1 is 1/12, and 14/1 is 1/14.  12:1 is more fuel than 14.7:1, so it is richer.
About the turbo. &nbsp;How much boost do you plan on running? &nbsp;Just about any compressor wheel will get you where you wanna go, unless you seriously plan on going to the limits ($$$<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>. &nbsp;It is a pretty standard trim (.60), so it'll be fine. &nbsp;
Also. &nbsp;Me personally, I don't care how big the intercooler is, I care about the efficiency, boost leak, and outlet temp. &nbsp;If I can get the same numbers on a 3"x3"x1" as a huge FMIC, I'd go with the smaller one, since larger intercoolers have to fill with pressure before air comes out, so the larger the IC, the more lag it creates.
I probably didn't help at all... sorry.
-Jeff

Jammin1911
10-09-2002, 03:28 PM
maybe you didnt help him much Jeff, but you answered a few questions I had, thanks! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

veil_side_
10-09-2002, 07:29 PM
Thanks alot Jeff, you helped me alot mang. &nbsp; <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>