contraption22
11-12-2006, 11:26 PM
Yesterday at Cecil was a good learning experience. Actually my first time in trying to tune with a wideband.
Here is the trouble I had... A/F at WOT was always pretty rich... always richer than 10:1. In fact, my final run at 22psi I was showing 9.49:1 A/F thru the traps. Yet my EGT was hot... 1550+! Puzzled by this, I was reluctant to take out some fuel pressure to lean out the car, afraid of catasrophe with the new engine. My brother's 2.4 Neon was seeing simiar readings, with a rich A/F and a hot EGT. His last pass would have been a good one, but he lifted when he saw the EGT's crest 1600.
So when I got home last night, I started to do some research. Found this on Hahn's website. Incidentally, Bill Hahn's the one that developed the PortFueler system that Joe is using on his Neon.
http://www.hahnracecraft.com/auto/tech/info.htm
To paraphrase, he basically says that an overly rich condition could cause hotter EGT's, with fuel burining in the exhaust manifold.
Any input guys? Thanks in advance
Here is the trouble I had... A/F at WOT was always pretty rich... always richer than 10:1. In fact, my final run at 22psi I was showing 9.49:1 A/F thru the traps. Yet my EGT was hot... 1550+! Puzzled by this, I was reluctant to take out some fuel pressure to lean out the car, afraid of catasrophe with the new engine. My brother's 2.4 Neon was seeing simiar readings, with a rich A/F and a hot EGT. His last pass would have been a good one, but he lifted when he saw the EGT's crest 1600.
So when I got home last night, I started to do some research. Found this on Hahn's website. Incidentally, Bill Hahn's the one that developed the PortFueler system that Joe is using on his Neon.
http://www.hahnracecraft.com/auto/tech/info.htm
To paraphrase, he basically says that an overly rich condition could cause hotter EGT's, with fuel burining in the exhaust manifold.
Any input guys? Thanks in advance