So I've been reading about exhaust mods here on the site and I'm a little confused, so I'm in "talk to me like I'm a five year old" mode here.

I did most of my serious wrench work back in the day when my car crushes were early 70's American muscle. First thing we'd do was slap some headers on the car, and it'd help. Big noise was not a goal then, but we got it while on our quest for more horsepower.

I'm happy with the sound of my XKR. I could use a more aggressive note, but it's my daily driver so I'm a fan of the quiet idle and gentle rumble at highway speeds. Don't want to lose that.

BUT... would love a little more power. That would be my goal here. Thinking of a tune, but the old-school me is screaming to do some kind of exhaust mod BEFORE a tune.

Does that make sense? And what would the most effective mod be? Just to do to the XKR-S setup?

Not trying to thread-duplicate here, but I've not seen a thread that addresses this (how best to maximize exhaust and tune on our cars) directly.

Thanks!

 

pk,
In the old days exhaust systems were very primitive and not designed with the aid of computer calculations. Plus many corners were cut to save money.

The XKR active exhaust is simply the best that there is. Thus changes can be made but only at the cost of something else. It becomes quite tricky when you do grand touring because what sounds good on short city hops can make long trips very fatiguing.

 

You can rule out headers due to price 5k

The next step would be free-flowing cats perhaps 400cell (not obnoxiously loud) with x-pipe in place of the dual resonators

The big benefit of the x pipe is the fact it acts as a crossover pipe merging the uneven firing of our cylinders specifically cyl 6 & 8

I would highly recommend a tune to go along with the these mods even loading up the factory xkr-s tune will lift power from 510 to 550ps

 

Mixed feelings about the exhaust. The stock box isn't the greatest thing ever. It's good at passing drive by sound checks by the Government but pretty sounds nothing like what a V6 F type can and that's a tragedy.

I'm running stock sized cats, an X and the stock box and it's just way too quiet. Really pointless to downshift or even run with the paddles. However I ended up with a stock box because my built muffler setup has some drone issues that I'm still working on.

Oh yeah, I'm pretty sure the stock exhaust is about optimized for economic efficiency. Surprisingly I didn't have a mileage change going to the stock box like I expected. Over sized pipes will cost efficiency.

 

I agree with Q&C on this one.

You say that you "... would love a little more power". What does that mean?
- When you dyno the car you get a piece of paper that says 525 HP or 550 HP or 900 HP instead of 510 HP?
- More low end torque that will give you longer black stripes on the pavement when you turn off the traction control?
- More mid-range torque? What speeds?

After you decide WHY you want more power you can have a solution designed to meet that requirement and look at what you will be giving up with the change(s).

 

Check Spires or Quicksilver for engineered exhaust systems.

 

I am going to be somewhat clinical and say that the need for more emanates from the need to advance the love affair.

There are 2 ways one can go about that, and both ways have merit since its all in the mind anyway- 1. tinker with perfection 2. advance the understanding and thus appreciation of the dish.

I can contribute to point number 2.
There was no expense or art spared in the exhaust system which actually starts at the intake. Everything possible has been done, even down to getting some sound back into cabin.
If Enzo Ferrari heard it he would say its a sophisticated, understated sound that fits the persona of an English gentlemanly luxury Grand Tourer. All while hinting at its power. That's its charm. With the lesser FType boy-racer, Jaguar has demonstrated it knows how to do hooligan quite well. The note of the XKR was a deliberate choice.

The XKRS is the one I somewhat disagree with. I think it tries too hard to be something that is somewhat conflicting. Like Paul McCartney playing Anthony Scaramucci.

 

Pulling away from a light at a gentlemanly pace the stock Cadillac Escalade beside me this morning had a better exhaust tone... OEM box is too effeminate on my combo. At least you knew the caddy had a V8 from the burble coming out the back. Heck, my wife's bone stock '02 Explorer with the anemic 4.6l V8 sounds better.

 

Its all a frame of mind.
I have the escalade.
Its all hat and no cowboy.

And no it sounds like a truck next to my jaguar's refined sportscar note.
Even women have said they love the note.
I can tell you from very long experience, not a single chic ever said to me I like the note of your chevy.
Then again it may be turning on blokes and I dint know it.

 

Changing the exhaust note is much different than the OPs request for increasing HP.

 

Good questions.

Would like to feel just a little more punch, more interested in "seat of the pants" feel than numbers. I've never dyno'd a car.
Low end and midrange torque more important.
Like I said, wouldn't mind a slightly more aggresive note but since it's a convertible and I spend a lot of time in it (and am on the phone hands-free a lot), I don't want it any louder at 60-80 mph.

 

I'm sure you've seen these posts as a forum regular.... I have no dog in this fight because I'm not modding my XK but I like to read a lot. Seems there are mixed reviews about performance mods, supporting Q&C's comments above. Looks like there is no cheap and easy mod to gain more "punch" and I doubt exhaust mods alone would gain anything noticeable. Here are a few related threads to peruse.

https://www.jaguarforums.com/forum/x...-xkr-s-111746/

https://www.jaguarforums.com/forum/x...-4-2-a-175450/

https://www.jaguarforums.com/forum/x...hwhile-175479/

 

Maybe a pulley and tune is more up your alley along with 200 cell cats?

 

Best post of the day. Well said.

 

Want more punch? Seat of the pants feel? Then buy this. Problem solved. Your Jag was designed for a different purpose than what you are looking for and there is no easy way to change that.

 

I know PK really loves his XK and hit that spot where the flames need a little rekindling.
Am I wrong in assuming that none of us really ever use the 510hp we have??
I would have to go out of my way to that, there are zero opportunities where I live.

What about if Stuart of AP Tuning could fabricate a custom valve for his exhaust, where he can bypass the muffler just for sound and fun?

 

Horse power wars are more about bragging rites or ego. I didn't need 510 but I wanted it. Do I use it , not really but it is fun to know that it is under your right foot. Would I have purchased the car if it had a 200 HP 4 banger , most likely not even though it has great looks. Now about the exhaust sound. I was fortunate to get a car with the PAE as an option. When on a long trip with the top down or up it is a pleasant sound and not overbearing. When I hit the flag button and jump on the go peddle the noise is outrageous. SO for me it is the best of both worlds. Now my question is for those looking for their ultimate sound what kind of noise are you looking for. Can you point to a youtube with the sound you are looking for and if you can can you replicate it. I've had several great sounding cars but this is the best of the lot . So what are you looking for.

 

This is a better video, as Nick Mason recodred it with mic in cockpit and one in the stadium. Listen to those pistons- btw size of a lawnmower engine. Show me how to get this sound please.

 

I don't get why PK is getting crucified for wanting more punch out of his xkr .

Exhaust mods are very common heck even Ferrari, Lamborghini and GTRs get these kind of mods done.

 

You crack me up Q&C one of your finest !