Alrighty... why don't you go onto the mustang forums and see how much power gains there are with a cat back exhaust system in supercharged applications... the answer is 5 maybe 10 hp for $1300-2000 spent. These aftermarket systems have bigger overall diameter tubing. The OEM manifolds of most modern day cars flow very well and it is very difficult to beat those manifolds (L.T headers when they fit) in terms of torque curve. Nobody in the LS motor or coyote motor world has PROVEN that there are gains to be had going bigger O.D on a cat back system with under 650hp. That's why nobody on this forum is chasing 5-10 hp gains for over $1500 in costs. It isn't worth the money. CAPRISTO, Frequency Intelligence, Quicksilver could have all created a downpipe/cat back system that opened up in diam. from the manifolds down and they DID NOT. I'm sure there were no gains and even possible torque losses at some points in the curve for them to arrive to the systems they currently sell.
With all that said. We respect you for sharing the information/the video and questioning the current situation. It is imporant and a great contribution!

 

I feel compelled to respond to this because there's a lot of paraphrasing and summary that is frankly inaccurate or misrepresentative.

What I actually said is that is what *Most* people want. The majority of customers are happy with the cost/benefit of either downpipes or an axle back exhaust. As a business when we develop products, we always have to look at things from the point of view of interchangeability. Does each component fit individually with stock components? With other Aftermarket components that are stock interchangeable? If we go down the route of designing an entire front-to-back exhaust that is say, 2.75" or 3" all the way through, now the consumer choice is "All or Nothing." Since the overwhelming majority of customers are not looking to spend the money for a complete system like that and are usually happy with individual parts, it makes sense to start out offering what MOST people want.

That being said - we have 2 F-Types here for product development and I would be more than happy to build you a larger diameter exhaust if that's what you would like. Will it produce any meaningful gains? We wouldn't know until we tested it. In this case, we don't anticipate some monster gains and as such are not 100% sure that the time & money to develop & test an entirely new product would yield any additional returns. It's speculation at that point.

One thing we are working on is to redesign our downpipes so that they are larger diameter initially and 2-piece, so it will facilitate connection to either a stock center section or a potentially larger diameter center section which would allow compatibility with a larger rear section.

Of course, everyone (or virtually everyone who comes to us) wants more HP. What I did say was that the overwhelming majority of the possible gains in power come from pulleys & tuning. And that our testing of headers & downpipes has confirmed this. And that for an exhaust for example. Let's even say that it makes.... 5-10BHP, when we can get anywhere from 50-110BHP on an R from tuning, what I said is that the PRIMARY reason people are buying an exhaust is for sound. We'll always strive to find power if it's possible and practical to do so for a price people are willing to pay. So it's not true that people did not ask us for more HP, what is true is that when purchasing an exhaust, it's probably not the primary objective for most people.

I never said anything like 'they were not made for that' - what I stated was that we have actually tested downpipes (and headers) and found no meaningful/statistically significant gains in power on this application. It is correct that we did find that running downpipes prevented the car from entering catalyst over temperature protection engine modes so they didn't *make* power but they do prevent power loss.

This is 100% correct. We have never tested a complete front to back larger tube system and found it to be ineffective. I don't know what you mean about 'giving me chances'... if you asked that question I'm sure I would have answered it as I have done here, that is to say no, we haven't done that.

As a small-medium sized business that's grown from nothing, with no investment and just a lot of hard work & sacrifice, we have to make decisions every day about what to put our limited resources into developing. Not just in JLR but across multiple brands. As we have grown and have some more resources, we have and do start to take on some more advanced and speculative projects. But there's a reason that aftermarket companies start off with the low hanging fruit, and that's because it is what appeals to the largest number of buyers and is the easiest to develop.

We're just as interested as you in trying all the possible combinations to see what we can achieve, and sometimes those things are dead ends. Sometimes they are dead ends until you find further solutions. We put a ton of money into researching headers, and we were pretty honest about the results, rather than just making them and flogging them with some BS numbers.

So.... the long and the short of it is - I'm happy to make you a system in whatever diameter you would like. We have the ability to do that if it is what you want.

 

Stuart, Thanks for checking in and I apologize if I paraphrased or remembered wrong.

I agree with this phrase from you: "That being said - we have 2 F-Types here for product development and I would be more than happy to build you a larger diameter exhaust if that's what you would like. Will it produce any meaningful gains? We wouldn't know until we tested it. In this case, we don't anticipate some monster gains and as such are not 100% sure that the time & money to develop & test an entirely new product would yield any additional returns. It's speculation at that point."

it "is" speculation, and I agree, not much might come of it. And from a business standpoint, being in that I used to have to pay for a building and two employees, myself, I can understand why you wouldn't make it for first priority. But, I have half the guys on this thread seemingly trying to discourage me from just plain having some fun with the mild-steel tubing I have at home and small-potatoes welder-- in come cases, vaguely citing VAP's product line and you personally, as reasons why it can never create gains that are "worth it". Which is why I tried to remember our conversation as best I could. As you said, and as I believe you and I discussed (I do remember you offering to work on a system for me) we have no idea if it will result in any gains--partly because you have NOT tested larger systems on the F-type R yet. There's no data. That was my point in bringing up the conversation. And you are explaining now, it's expensive to get that data. I totally understand--we discussed that as well. And, I appreciate the offer, but... I don't have the $$ to throw around to develop something by someone else's hand, or want to waste your time on something that is just an experiment. It would cost a ton of money. I can make a crude but effective entire manifold-back exhaust system for myself out of mild steel as a proto, for far less than $1000. And have fun doing it, and testing it. If it fails, or I just don't like it? The tubing goes back into the tubing heap, for the next project.

Everyone keeps citing "worth it"? Worth it to who? To me, $1-2k to alter the already great sound of the F-type without knowing if it adds HP may not be worth it to "me", unless it really sounds good to me--and so far, I have not heard anything I like better than the stock sound. To each his own.

You also mentioned In your response:
"One thing we are working on is to redesign our downpipes so that they are larger diameter initially and 2-piece, so it will facilitate connection to either a stock center section or a potentially larger diameter center section which would allow compatibility with a larger rear section. "

yes, please....