Tuning advice for 2015 Roush RS2.

[AP3X83]

I picked up a 2015 Roush Rs2 mustang.
Seller claimed 750 hp.
Not sure if this is at the flywheel? Or at the wheels.
I'm not a tuner, never owned a mustang or a aftermarket boosted car.
Took the car in this morning to get a baseline on the dyno!
Well on the drive there the car lost about a Honda civic worth of power. Not really!
The dyno numbers to me were lower than what I've seen from some similar cars on you tube.
I'm attaching dyno sheet.
And wonder where should I start looking to find more power?
Are these numbers normal, reasonable?
Advice is greatly appreciated.

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[robvas]

750 flywheel...

what size is the pulley? It might say on it

turn it up to 10lbs, get a custom tune on it from your favorite tuner, and spin that sumbit to 7500rpm

add some headers and maybe a bigger TB and air intake for more power. Hard to say without what knowing is on it now

 

[Pistol_91]

AFR looks lean for an FI car. Could be inaccurate though...

 

[robvas]

AFR looks lean for an FI car. Could be inaccurate though...

Since it's on the dyno graph I would assume that's one they stick in the tailpipe and those are usually a little off

would be nice to see a datalog from a pull though

 

[LethalSteveG]

That looks like a ROUSH tune file on the car in which, that power is going to be normal for it. ROUSH really limit the tunes on these cars to stay 50 state legal.

Swapping to a custom tune will help it a lot. The next issue you will need to address with adding more power is the factory cats will not last. I would look at headers as well.

We can help you out with the device/tune and headers if you want to go this route! Let me know.
https://www.lethalperformance.com/s.../ford-mustang-v8-gt/2015-2017-ford-mustang-gt

 

[Goterr0r]

A tune will really wake that car up, but as Lethal mentions the cats will go pretty quickly. You can get LTH or we just gutted mine when i had that blower on an 18. Also, heat is a really big killer of power with that blower. I see you have the triple pass listed as an upgrade, but that will only help so much. Make sure you monitor IAT2 as a parameter using something like an Autometer Interceptor gauge or even just the OBD Fusion app with your phone. Once that IAT2 temp gets above 140-150 it starts pulling power like crazy. and that temp will get there really quick with back to back pulls. Also keep a close eye out on the intercooler pump. Those or the relay that controls them can fail pretty often.

 

[robvas]

A tune will really wake that car up, but as Lethal mentions the cats will go pretty quickly. You can get LTH or we just gutted mine when i had that blower on an 18. Also, heat is a really big killer of power with that blower. I see you have the triple pass listed as an upgrade, but that will only help so much. Make sure you monitor IAT2 as a parameter using something like an Autometer Interceptor gauge or even just the OBD Fusion app with your phone. Once that IAT2 temp gets above 140-150 it starts pulling power like crazy. and that temp will get there really quick with back to back pulls. Also keep a close eye out on the intercooler pump. Those or the relay that controls them can fail pretty often.

It's a 15-17 blower, not the 18+ Roush

 

[Goterr0r]

It's a 15-17 blower, not the 18+ Roush

My brain is still on Monday... Thanks for pointing that out. He won't have heat soak no where near as bad as i did...

 

[Pistol_91]

Since it's on the dyno graph I would assume that's one they stick in the tailpipe and those are usually a little off

would be nice to see a datalog from a pull though

Exactly my thoughts

 

[AP3X83]

Thanks all for the suggestions and advice.
Couple of questions.
Is the car now basically at the limit of melting cats?
If so how can I get more power and pass emissions?
Would a non roush tune improve performance even without improving power?
The cars is pretty nice now, however I was hoping the dyno pulls showed about 650hp.

 

[AP3X83]

750 flywheel...

what size is the pulley? It might say on it

turn it up to 10lbs, get a custom tune on it from your favorite tuner, and spin that sumbit to 7500rpm

add some headers and maybe a bigger TB and air intake for more power. Hard to say without what knowing is on it now

Pulley is an 85mm .
Would an 82 mm pulley and tune gain 50rwhp?
Not wanting to go catless yet.

 

[Grimreaper]

Should pretty easily. 80mm pump 93 and tune with moderate timing should be bit over 600-640 whp.

Id add just a tune for what you have on the 85mm and pulley down after. You may be content. Very reliable at that point and keeps the timing higher on pump gas. Having to pull timing pushes more heat out the exhaust and can cook the cats over time. Personally I'd learn to log and monitor for the fuel quality in your area. Few ounces of boostane can help too.

Otherwise looks normal for a Roush 85mm tune. You'll likely need a BAP for more boost or a dw400 pump swap

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