Tune predictions

Put my car on the dyno for a pre tune comparison test. Top swap withVS cam3.4 pulley and ported blower. Made 251 HP and 262 tq.wideband. read 11:9. So how much do you think ill gain from a tune? What ratio do you aim for obviously. Its running a little rich

11.9 is lean.

You want 11.4ish for a boosted car.

11.9 sounds right about perfect for your setup. Is it already tuned? What kind of timing do you see? Any knock?

no tune yet. just wanted a before tune example.

Well seeing that you're probably getting some knock detonation from the 11.9 a/f and if you go back down to 11.3-11.5 you'd probably pick up some power. Not much. Maybe 5-10 hp. Were you scanning it while on the dyno? Post a graph up?

I wouldnt run the car all out with no "tune", thats sorta like playing with fire.

I was trying to sort it out before paying someone to tune. It was pulling timing. It def seemed to get worse when it got hot. I installed a fuel pressure gauge and found the pressure falling as car warmed up. I scoped my fuel pump and found an issue. I replaced the fuel pump and wow what a diff. It went to 281/291 and now my fuel trim is 10:4 at WOT. Now I am going to leave it alone and have it tuned.

Originally Posted by fry626

11.9 sounds right about perfect for your setup. Is it already tuned? What kind of timing do you see? Any knock?

Play with an M90 on a high comp bottom end before?

Dyno at different AFRs?

Run longevity/durability tests at different AFRs?

Im not looking to be bashed or for your opinion on what I do. If it blows up tom. I dont care. Im just having fun. I can get engines all day long. I bought the car with the motor in the trunk. This is how Im learning and having fun at the same time! I was just cur. how much more I could realistically gain from a good tune.