Dyno Results Rich A/F Ratio Question

[AutobahnRacer]

My Dyno Sheet

[JET02WRX]

You can't really base power from what your car is doing A/F-wise. Your question is... weird. Meaning, yeah if your car is super lean or super rich you aren' making optimal power. But that AFR looks ok, so if yours is close.... Is your application forced induction or N/A?

[AutobahnRacer]

not my dyno sheet remember, only thing that looks like my sheet is the A/F its similar.

its N/A

im just trieing to figure out why i have so much less hp than stock. I ran 180 whp and trq on the dyno today. Stock is 250 to the flywheel. And im obviously not even close when you convert it

[AutobahnRacer]

see above my chart **updated**

[RyanG]

first things first.. what car? what mods?

[AutobahnRacer]

2001 Chrysler 300m 117k, Short Ram intake, brand new spark plugs, exhaust: no resonators, stock pipeing and cats, both cats join as a y-pipe, pipe up to cherry bomb extreme muffler.

no other mods

where the hell is all my power gone. im fricking short by over 40 hp and tq from stock. Someone help me out. How am i loosing all this power?

[lagos]

Drive train loss from auto trans plays a big role in it.

250hp x 20% = 50hp loss = 200whp
You made 180, so thats 20hp that is missing.

Part of that could be heat soak on a hot day, or your intake/exhaust mods might have actually cost you some power from reduced back pressure.

There is a small dip in your power band at 4,500 rpm. The ecu could have pulled a little timing there from heat soak or low grade fuel and cost you a little bit of peak power. You can try running 93 octane if your not doing so already.

Other then that, I would say that your power is close to where it should be.

[JET02WRX]

Yep, Lagos is right.... auto trannys usually show lower numbers than the same car with a manual on the dyno... Heres a for instance.... Most manual 2.0L WRX's put down somewhere in the neighborhood of 285-300hp with my same mods. I put down 256 with an auto. Thats about 15-20% less than the manual. Sounds like you are right in line. The only car i've ever seen put down similar numbers as a manual are the GM LS1 auto cars. I had a 2001 WS6 auto, and i put down 298hp. Thats pretty much in the range of the manuals.

What "gear" did they dyno you in? That also makes a difference. In the end... what matters is trap speed and ET. Take it to the track to get a true sense of your power.

[AutobahnRacer]

well the drive train explanation is a big relief and that u explain how im almost right on, and once i get tuned should add a little bit. your words are a big sigh of relief, plus i figure with age comes loss of hp.

so basically i am right on, thank you so much. what a relief that im not off as far as i thought

and gear was third i belive because he was saying how automatics with tractions control sense sometghing wrong adn shift or something like that didnt really understand it

[lagos]

and now you know why people hate so much on the auto trans.
Some of them are even reported to loose as much as 25%.

[AutobahnRacer]

thank you soooooooo incredibly much again. you guys have been so helpful and saved me from freaking out over this like i have been. lol too bad ive been to busy researching this and didnt pay attention to class.

[Vince@R/TTuning]

hey mike, should have asked about the numbers at the shop i would have explained that to ya, i just assumed you had an idea it would lay that down. Actually 20-25% is a pretty good acceptable loss of power through an automatic. I have seen many with over 30% drivetrain loss through an auto

also we had to dyno it in second gear cause when we did it in third the rev limiter was lowered to 5kish. That happens alot when you dyno certain vehicles with traction control....

[AutobahnRacer]

when i was at the shop i was satisfied with the numbers and it seemed right in my head but when i start thinking excesivly about something i dont take all element into considerations and i end up with a situation like this where i completly forgot to take automatic transmission into ocnsideration. (becuase last car was manual, cuz didnt have to worry about it)

but i am looking forward to coming back to the shop for my tune. You guys are very professional and have a great shop.

See you when the harness comes in.

[Vince@R/TTuning]

Originally Posted by Carministrator

when i was at the shop i was satisfied with the numbers and it seemed right in my head but when i start thinking excesivly about something i dont take all element into considerations and i end up with a situation like this where i completly forgot to take automatic transmission into ocnsideration. (becuase last car was manual, cuz didnt have to worry about it)

but i am looking forward to coming back to the shop for my tune. You guys are very professional and have a great shop.

See you when the harness comes in.

awesome, thanx again and i look forward to gettin ya all tuned...

[AutobahnRacer]

sent you a PM