Back in March we saw in a post about the side pipes and in it a comment from "Quick Time Performance" that stated they were working with FRPP on a set of electronic cutouts for the BOSS that replaced those spacers. I recently sent them a PM to ask for an update and they just informed me that the should have them ready in July. They stated they were looking for a BOSS in the NY/NJ area to work out the final installation instructions. If anyone is interested in helping with that they should PM "Quick Time".

This will most likely be my only mod......

 

so is the point of these to force all exhaust out the side pipes for track use?

 

No, from what I understand, they just remove the spacer, or put it in...electronically. So if you want it quieter, you flip the switch one way..louder flip it the other way. Maybe it's more complex than that, but it just controls the sound output from the side exhaust

 

There is supposed to be a slight increase in HP with the discs out so for those of us not wanting the car loud all the time the valves will be a nice option. It would be nice if someone checked this on a dyno to confirm how much.

 

I suppose this will work for some but the expense and having to add wire and switches to the car do not interest me. There is a good sound to be had depending on the individual with discs. I will run them out on the track as having them open will be less restrictive but I doubt it will be anything you would even notice. As the engineers said the exhaust was pretty free flowing before adding the side pipes on the Boss. Plus they are super easy to remove and install for track days.

 

If you pull them for track time it makes more sense to
get the electronic valves

 

It was the exhaust engineer that stated there was an increase.

 

Not really, what I am saying is the cost and cutting a hole in the floor and drilling a mount in the dash or console is not worth the two minutes to remove for the track, IMO. I don't know how these will work, one size closed and open or a variable adjustment but I think 3/4 and 7/8 will work out well for me, just not sure which I will use for the long term yet. The hardest part of pulling them is getting the jack over to the car.

 

Worried about cost? And only two minutes to take them out and put them in after the track?

 

I doubt I'll buy them but if unrestricted added close to 10 HP I'm in. Their existing valves use remote control. Since Ford had this in mind all along I'm hopeful they have accessible power close by.

 

Depends on price for me Rick. But I like discs out

 

Rick I would say that is not even close. If it gained more then 1 or even 2 HP that would be a lot. You would have to do 100 dyno runs and average them out even to see the difference since the variations in each pull will be more then the HP gain with them out, JMO.

 

Notice I said if. . I'm sure you're right but it would be nice if someone would verify that.

With both Scott and Dave putting their discs back in I'm sure I'll be there with them. But I will try it with them out for sure.

 

I thought black bullit did

 

Although I have no DATA for my opinion (yet), I tend to agree with Scott that the hp gain by running no restrictions in the side exhausts will be lost in the measurement uncertainty. Another words very small gain (if any) and as stated you will need a number of dyno runs to get any hp gain of statistical significance. The exhaust system on the Boss as designed is free flowing without much backpressure.

But hey, it will sure sound better and I will remove the discs for my car tracking events if for nothing else the sound....

 

black_bullitt did a dyno pull and there were clearly some gains. Peak was only 4 hp more, but if you look at the curve between ~5000 and 7500 RPM it looks to be more like 10 hp. I've seen 20 rwhp with an offroad-x on other S197s. Yes the factory manfolds flow well, but the discs are a restriction as are the rear mufflers. Removing them will free up hp.

The car is positively not too loud IMO with the discs out. In fact, I'm toying with a more free flowing axle back. The guys at the track are giving me crap about having the "stealth" car because you can hardly hear it. There's virtually no sound coming from the axle backs. It would be nice if someone would try an offroad x to see what kind of gain is possible on track. Of course you'd need an after-market tuner to turn off rear O2s if you don't want a CEL constantly. I'd also be interested in just seeing what a non-restrictive Borla or Corsa axle back would do for both sound and hp. Also, I'm guessing you could drop 20+ lbs by going with something like this: http://www.lethalperformance.com/07-...xhaust-p-13275

 

An engineer that worked on the exhaust system stated on this forum there was a decrease in back pressure and increase in HP by removing the discs. That's good enough for me.

Is there a link to black bullets dyno pull?

 

I have a dyno video up on youtube (linked in one of the threads in this section). As Gary just stated, with discs removed it saw a gain of 4 peak rwhp. The two dyno pulls were no more than 10 minutes apart - we didn't even pull the car off the rollers to remove the discs. That said, that was just a quick stock pull, remove the discs, and pull again. Certainly not a series of pulls to get an idea of an average gain, but certainly something to have fun with.

As for the noise levels, I also agree with Gary here. The car certainly has a nice(r) rumble with the discs out, but it's nowhere near overly loud. I don't know how many people have come up to me at get togethers or car shows saying they saw the video of the BOSS at the 1/8th mile drag strip, or were there watching the runs in person, and commented on how quiet the car was, and how stupidly fast it was for such a quiet car. But I just had a guy on one of the local forums post that he was right next to me (discs out) and again commented on how quiet the car was. Granted I wasn't cruising the streets at WOT, but still. Maybe my sense of what's loud is skewed though, as the Bullitt, when last operational, was equipped with SLP o/r X-pipe and LM II catback system... THAT was loud.


Edit: here's the video thread https://themustangsource.com/f813/vi...emoval-494285/

 

Post #114: https://themustangsource.com/f813/re...493062/index6/

 

That was the other thing about the "stealth" part. They didn't hear me catching up to them until I was filling their mirrors