Stoich?
#21
Cpt. Slow
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You're running around 9-10psi, on track, and only around 12.2afr. Although that's probably ok for the street, I might consider running 3-4 tenths richer to help keep the motor happy. I'm not sure if it's just your tune or the req fuel change, but you actually start all of your WOT pulls at 11.7-11.8 (what I would recommend), but EGO leans it out by redline to your 12.2 target. You're also 2-3 too advanced in my book, although you're proving me wrong by not blowing up motors in 75 track days (taken from your clutch thread). If you have a local dyno, do a couple pulls in the 1:1 gear until power stabilizes, then take 2-3 degrees out and see if it makes a significant difference. If it does, you're probably safe. If it doesn't, it means you have extra timing harming the engine.
I typically pull 1 degree for every psi of boost, starting at 28* at 100kpa. You drop 1 degree for 1psi, then 4 degrees every 2psi. Seems a bit non-linear, then again as I said, you're not blowing engines, so maybe ignore me.
I typically pull 1 degree for every psi of boost, starting at 28* at 100kpa. You drop 1 degree for 1psi, then 4 degrees every 2psi. Seems a bit non-linear, then again as I said, you're not blowing engines, so maybe ignore me.
#22
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Curly,
Thanks for taking a look.
I noticed the AFR going up slightly at WOT in Fifth gear, from 12.3 or so to 12.5, and hanging at 12.5 even while we were accelerating. I certainly couldn't keep an eye on it safely, but I did notice it. I had made no other changes to the tune besides the Req Fuel, and pulling a little from the cranking box in the VE Table. What would cause that? Going uphill on the back straight???
That's one of the few times I've actually reached 10 psi. 9.7-9.8 is pretty normal, so I don't usually get into the upper row of the AFR Table. If I reduced every row by two tenths, essentially shifting everything down one row, what should I have in the 100 kPa row?
I actually had a little more advance in an earlier tune, and pulled some based on your recommendation to another poster. I saw no loss of performance. I'll pull a little more.
Thanks again,
BTW, the engine is a part-out piece I purchased in 2018 after I blew the oil pump at Summit Point. All the miles I put on it were pretty hard.
Thanks for taking a look.
I noticed the AFR going up slightly at WOT in Fifth gear, from 12.3 or so to 12.5, and hanging at 12.5 even while we were accelerating. I certainly couldn't keep an eye on it safely, but I did notice it. I had made no other changes to the tune besides the Req Fuel, and pulling a little from the cranking box in the VE Table. What would cause that? Going uphill on the back straight???
That's one of the few times I've actually reached 10 psi. 9.7-9.8 is pretty normal, so I don't usually get into the upper row of the AFR Table. If I reduced every row by two tenths, essentially shifting everything down one row, what should I have in the 100 kPa row?
I actually had a little more advance in an earlier tune, and pulled some based on your recommendation to another poster. I saw no loss of performance. I'll pull a little more.
Thanks again,
BTW, the engine is a part-out piece I purchased in 2018 after I blew the oil pump at Summit Point. All the miles I put on it were pretty hard.
Last edited by poormxdad; 04-26-2024 at 07:05 AM.
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