Dyno tuned my Paxton '06 coupe today

plumcrazy

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I have several dyno runs on my car. Some before and some after the addition of the new exhaust. If I can figure out how to get them scanned I will post them here. My graphs have a much finer scale than the ones posted here so it is easier to see exact A/F at any RPM. Before the exhaust mods the car was running in the 11s after 3200 RPM (when boost kicks in on a Paxton). From 3700 RPM up it was below 11.5:1 to lift off. Average about 11.2:1. I actually thought it was too rich as it did smoke some on the track. It was safe though.

After the exhaust mods the A/F was in the high 11s hitting 12.2:1 at 5100 RPM. Remember that this will lean out further on real roads with more air being forced into engine via the ram air effect. Also it will get leaner as the car heat soaks. I can actually see this on three dyno runs before exhaust mods. A/F got leaner after each run but was still plenty safe.

Running leaner may be ok for short bursts and for tracks with lots of twisties and short straights as you're not in boost for long periods. However if you run it for extended periods on warm days on tracks with long straights (like some super speedways - Pocono, MIS, Daytona, etc.) then you have a higher likelihood for problems. My blow up took place on one of these tracks that has extremely long straights. Now I'm doing forged internals and have already had DC Performance redo the PCM to be richer.

Again I'm not saying you are in fact running lean, I can't honestly tell because the scale on the dyno run is not fine enough. I would call the shop and ask if they can print you a graph of just A/F with a finer scale. Each block on my graphs is 0.1 That way you would know for sure. But if you are in the 12s on a dyno I would say you are in fact too lean. That's from a rather expensive lesson learned. Good luck either way.

from what i have been told, if you wanna track an SRT or gen2 and run hard, there are a few other things you need to be adding to the car other than forged internals. id bet bob pantax knows a few of them and certainly DC and woodhouse do. make sure to get a hold of them and get their opinions
 

pteam

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For reference here is my dyno chart superchaged by woodhouse and tuned by dc performance (installed by woodhouse)
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