| I posted this 2 months ago about my most recent dyno tuning after the 60mm throttle body install . On the surface it looked like there were no power gains. Well, the weather was hotter and more humid than last November and the power level was the same. So I guess you could argue that their is more power if the conditions were the same. I recently installed my AEM wideband o2 and have been watching and noticing the readings. I have noticed that the a/f ratio in WOT 4rth gear was reading 10:7:1 where as it should have been displaying 11:5:1 ???? I watched the RPM rise to about 6k - 6.5k range before I let off ( was going too fast on the road for safety at this point ). I originally attributed this to the engine having a load on it different than the "simulated" load on the dyno. But I would have thought that if this was true, the a/f would have been leaner not richer. From talking to Ash and Andy at Xotic Motorsports ~ they both said the same thing ****
"The variation we are seeing in your wideband information as compared to what we saw at xotic tells me that their wideband sniffer had an issue of some sort – likely a small leak somewhere between the end of the hose and the sensor itself allowing fresh air to enter into the gas stream and cause it to show a slightly leaner mixture. The variation in A/F should be addressed – it is likely the #1 reason the car dyno’d low on power. I know the heat played a role as well, but at that power level, the difference in power between a 10.7:1 mixture vs. 11.5:1 is significant."
****
Short Story The is more power to be had with a 60mm throtle body install. How much -- I don't know and will not know because I have installed a 3 inch exhaust system since August. I don't know if the a/f reading on the dyno was jacked up from the beginning or on day 2. I do remember us switching the a/f reading from one tail pipe to the other and noticing a significant variance in a/f which told us that I had an exhaust leak somewhere. We assumed that this was from the cat back ( meaning after the x-pipe ).
I have to imagine that the variance in power between 10:7:1 to 11:5:1 has to be significant ... I liken it to pump tune 11:5:1 to race 12:1:1 ( well maybe not that extreme ) For those who don't remember -- I made approx 650rwhp with new mods (jwt 500 cams -previously had jwt 400,eagle rods, fischer pulley, 60mm throttle bodies,plus whatever else I am forgetting ~ but these are the main mods ) and 666rwhp without the new mods on the same dyno on a cooler day. The real question is, which day was the a/f ratio jacked up because I went to the dyno on two different days. I know that I have proposed more questions than answers, but I wanted to potentially corrrect my previous post from 2 months ago where I stated that their are no gains from a 60MM throttle body install.
I had planned to dyno again in November when the weather is cooler anyway because I was curious to see the impact of the 3 inch cat back exhaust. This time I will just have to retune the car ..
looks like I finally will buy a Zem :)
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"....Thanks captain obvious, would you recommend air to resolve a low tire pressure situation? coolant to keep temps down? perhaps a battery for electrical devices? " ... LJZTT on June 10, 2006 at 6:36 PM
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"as useless as an EGT Gauge..." *shakes head* Its comments
like this that hold the Z32 community back. " ....Z-Jay (Edmonton, AB) on April 21, 2006 at 11:46 AM "Somebody give this man a medal. Arguing with kenny is like being in the special olympics" ....ENVYMYZ on November 01, 2005 at 11:59 PM " .. going back and forth with you on a stupid point is like watching a retarded kid double dribble in basketball, you get tired of calling foul all day" ... Slowninja(GT28RS Inconel Z) on October 03, 2005 at 8:43 AM "the only chips you know about are Doritos. =)" ...ZEngineer on June 11, 2005 at 4:23 PM "....These posts only serve to make you look even worse, its gotten so bad it even makes me look bad to reply to you...." maglito on January 22, 2005 at 3:11 AM "What, are you afraid that only a couple of good ones have rolled off the production lines and the rest are crap?? ... Its mechanics not the stockmarket." ... ZisLuv on May 03, 2004 at 6:12 PM 
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