Hi all, I got my 2013 mustang gt last summer and I'm relatively new to the V8 scene. Over the past few months, I've added some go fast parts along with the requisite tuning and the results have been less than stellar. Approximately 402whp @ 398tq.

Car setup:
2013 Mustang GT, base (no track pack, no brembo)
C&L intake
ARH longtubes with high flow cats and H-pipe
Roush axlebacks


I had the shop install the longtubes for me and it originally dyno'd 395hp@385tq after tuning. To my knowledge, they did not perform a baseline dyno. I was not there for the dyno session so I don't know what was done or how it was done. I figured that the lack of intake was hurting the numbers so I added the intake a month later. This time I stayed to watch the dyno/tuning session. The initial baseline yielded 388hp@355tq! After a few hours of tuning, they finally managed the aforementioned 402hp@398tq. I asked if they thought the car was down on power to which they replied that I shouldn't go by what I read on the internet. I think that if it was kind of shy of the numbers others are getting, I wouldn't be bothered. But some people are getting higher numbers with just an intake/tune!

I'm at a loss really. While I'm sure 20-30whp won't hurt me in the long run, I'd want to know if i'm missing that hp because there's something wrong the car or if the tuning is off.

Thoughts/opinions? Am I just being paranoid?

Sidenote: I'm not completely sure they dyno'd the car in 5th gear; but I don't think that'd be the cause for such a low hp number.

 

Dynos and conditions can vary really, ambient temperatures, etc. There is so many factors to consider I wouldn't worry about it.

 

Was this a Mustang or Dynojet dyno?

 

Sorry, this was on a Dynojet. Ambient temps were in the low 70's.

 

run it at the track and compare your mph to others with similar mods. that will be more accurate than any dyno.

 

This ^^^^

 

Well for one you should have stuck with the stock intake. The numbers don't look awful but they're just numbers and as stated take it to the track. Does this shop have any experience tuning these cars?

 

Just curious but why stay with the stock intake?

This is a local shop that specializes in mustangs but I'm not sure how versed they are in dealing with the new 5.0.

 

Because it's been proven to work better than any of the aftermarket ones. Where in NY are they located?

 

Deer Park