Was it the Carbon Clean'n or the Port n'Polish'n?

[maxbhp]

As many of you know I dyno'd my car at GMG's dyno cell on 9/3. Car was stock, 17,700 miles. 76F temp in dyno cell.
Here were the results which I was pleased with overall.



Koolade came by and worked on the valve cleaning while the IM was sent to SilverRS4 for the P&P. Silver was impressed with the manifold and didn't think it had even seen 18k miles.
The valves weren't too bad either, so I was not expecting that much of a gain.
The 304 whp on the Mustang dyno equates to 405 bhp or so.

Dyno'd today - same dyno - same operator, 26 days later. Today temp was 92F in dyno cell before we began, still under 18k miles on car.



3 runs today. Very happy with the results. Dyno tech thinks the first one was high because car was still cool. Oil temp was only at 212F after second pull.
If 330 whp is what I am putting down, that would equate to about 440 bhp.
If my car really came with 420bhp from the factory, does the P&P give me 20 bhp more?

Here is a graph with a pull from before the clean/polishing and one of the post clean pulls.



As you can see my peak torque is slightly lower, but the torque curve is much smoother and healthier.

I ran the car hard this evening on my way home. It is still warm outside but definitely cooling down. Car ran like a banshee. It really feels quicker through the revs.
I used to not use the S button because I did not like the throttle response and my shifts were not smooth. Over time, I have engaged the S mode much more and have not had the throttle problem - thinking that I am just much more used to the car and therefore a much smoother driver.
Not the case. The S button is much more noticeable - almost to the point where I don't like it anymore again. Just my seat of the pants dyno and impression.

[jalas]

Nice gains. Do you happen to have access to VAGCOM data for timing and MAF readings?

If you go to my part 2 of the CC clean + PP I was amazed at how much powerful the car felt. Night and day.

[2manytoys]

Good stuff. Given the amount of carbon on the valves you seem to have a pretty good gain from the clean. :-)

I've said this before, when you need to rev the car to 8000 rpm the inlet needs to be top-notch. I think this is why a diesel or even a normal 6000 red-lined car wont have a major issue until it's really bad.

How's that 5500 rpm "turbo-boost" now?

[Justincredible]

I used to not use the S button because I did not like the throttle response and my shifts were not smooth. Over time, I have engaged the S mode much more and have not had the throttle problem - thinking that I am just much more used to the car and therefore a much smoother driver.
Not the case. The S button is much more noticeable - almost to the point where I don't like it anymore again. Just my seat of the pants dyno and impression.

Nice post but the S button does nothing for actual power on the car. Any pictures of how bad the carbon was?

[iconoclast]

great news... glad to see the car is back to factory numbers (or better) and running flawlessly now.

[WinterRunner]

Considering 295-305 AWHP from a mustang dyno is a healthy RS4, I bet you picked up a good 20 or so from the P&P. IIRC, your carbon was pretty mild so Im not sure, nor do I think it made a big impact on your #'s, maybe 2-4 WHP at most. Excellent, thanks for sharing. FWIW, my healthy, (less than 2K miles after a clean) RS4 put down right around 300 WHP.

[koolade9]

Nice post but the S button does nothing for actual power on the car. Any pictures of how bad the carbon was?

Think of it as 304hp * 'S' throttle response vs. 330hp * 'S' throttle response...more pronounced...

There should be pics in the CB thread

New experiment...Arthur, pull you manifold and have it p&p'd, as you're honestly probably the only one that wouldn't clean the valves while it's off and then we can see p&p gains

[ArthurPE]

lol
I wouldn't spend my $$$ on quasi P&P
I'd go extrude honed, but a few HP isn't meaningful to me

~9% gain...
using the atm data, 1/2 is due to that
so net ~ 4.5% or 14 HP or so, I can buy that
2/3 manifold, 1/3 cleaning (although his were pretty clean), 3% and 1.5%, 10 & 5 HP respectively

but >9% without an increase of comp or displace or revs???
nope
that would imply an increase of vol eff of 9%, from say 0.95 to almost 1.04

Think of it as 304hp * 'S' throttle response vs. 330hp * 'S' throttle response...more pronounced...

There should be pics in the CB thread

New experiment...Arthur, pull you manifold and have it p&p'd, as you're honestly probably the only one that wouldn't clean the valves while it's off and then we can see p&p gains

[maxbhp]

Think of it as 304hp * 'S' throttle response vs. 330hp * 'S' throttle response...more pronounced...

There should be pics in the CB thread

New experiment...Arthur, pull you manifold and have it p&p'd, as you're honestly probably the only one that wouldn't clean the valves while it's off and then we can see p&p gains

Thats exactly what I meant about the S button. Obviously not any more horsepower or even faster, just throttle response a touch more sensitive. Throttle now has 330hp responding to it more sensitively rather than 304hp

Those that bought their car new might remember the issue some people had with the S mode engaged. We enjoyed the slightly louder noise but not the overly-sensitive throttle, which you definitely notice most when shifting. This led many people to pull the exhaust valve hose and plug it - keeping the flaps in the exhaust permanatly open and therefore no need to us S-mode (this was before we had any real aftermarket exhaust options). I have the stock exhaust and Eurowheel - S button on wheel. I enjoy hitting it when getting on the throttle hard for some spirited driving but wouldn't notice the over-sensitive throttle as much anymore latlely. Just saying I don't like the button anymore.

[iconoclast]

so the popular consensus is to pass on the port and polish or to go with it???

[koolade9]

so the popular consensus is to pass on the port and polish or to go with it???

go with it

[Retsujou]

so the popular consensus is to pass on the port and polish or to go with it???

There is no significant data as to whether it aids or does make things worse. There is some speculation based from other type of engines that it does help, however no one knows to what extent with this complicated engine set-up. So if you are conservative, then skip it, if you do not care about your warranty, go for it.

[Justincredible]

Think of it as 304hp * 'S' throttle response vs. 330hp * 'S' throttle response...more pronounced...

There should be pics in the CB thread

]

Ahhh noted and as it should with both the pictures and the throttle response.. that makes much more sense... great work.