Hi guys, I'm enjoying the heck out of my 2009 XK but I hate the stock exhaust! I've got a wild hair up my rear and will get rid of the stock exhaust. My #1 goal is performance... but I don't want it to be annoying. I am thinking of going with Magna Flow muffler up front and straight pipe all the way to the rear. I am thinking about adding a X pipe just rear of the muffler. Any suggestions? Pro's Con's?

 

If after performance go 200cell cats + X pipe and a tune to suit

 

Read Ranchero50’s build thread.
Good stuff, and his experience with exhaust mods.

 

I too am thinking of upgrading the exhaust on my 4.2 N/A convertible. I spoke with Chris at Mina and I will be buying one sometime soon. From what Chris told me it's best to stick with a 2.25" pipe on the aftermarket exhaust. That's the diameter size on the Mina. It'll match the size of the stock pipes which in turn will not have an adverse effect on the car's low end torque.

 

Save your money and trade up to a 4.2L XKR (or 5.0L if your budget allows). An exhaust mod, without more, won't give you a significant performance improvement.

 

That's true. The only change in a N/A will be sound. Not performance.

 

thanks for the suggestions guys. I just got the car, so I won't be getting rid of her. She is in pristine condition, I doubt I would find another in the same condition for what I paid. So if all I get is a better sounding CAT, so be it. I can live with it.

 

I had Magnaflow mufflers swapped for the OEM muffler and it was horrible. The back pressure dropped too low and the car was a dog. Worst money spent. Threw the mufflers in the dumpster and put the old muffler back on.

If you want to change out the exhaust, go for an engineered system. Larini is one of the best, regardless the marque.

 

You DO realize that a capable exhaust system will cost at least a couple grand, right?

 

I think you'll be just fine with a performance exhaust alone. Money spent on gaining more high end horsepower is kinda of a waste when it comes to driving here in Southern California. Driving in So Cal is mostly launching the car from stop light to stop light on surface streets and bumper to bumper traffic on the freeways. That said, my 4.2 N/A 300 horsepower convertible gets the job done. Just drop the transmission into the Sport Mode and she'll launch like a jet.

Once I move out to Palm Springs then that's another story. Miles of open road begs for an "R" but again. here in So Cal not so much. Enjoy your new ride!

 

If you can live with just sound improvement on an XK, and not spend a whole lot, find yourself a used back-box from a 2007-2009 XKR. The valves are naturally open without a vacuum supply, so you'll have a better sound, and no worries about drone.

 

I heard a XK with a modified exhaust and was shocked it sounded amazing.
I could not believe it was a NA 4.2

 

False statement

X-pipe & free flowing cats will not only increase sound but performance as well

 

A catback exhaust is the only mod I suggested. An X-pipe and free flowing cats are additional mods. So, with just a catback exhaust the only gain is sound. The horsepower gains alone are negligible.

 

I contacted Larini to see if they offered an exhaust for my XK 4.2. They responded promptly and have an awesome system avail. $1100 + shipping for the muffler, 30 days lead time to construct. Club Sports Center section is an additional $600 . They guarantee a noticeable torque feel with a flat torque band across the power curve. I’m sold!

Center section

Sports muffler

 

 

Man that sounds MEAN!!!

 

Absolutely love this system and well priced !!

 

Sorry but with the echo of the room it wouldn't sell me on buying one. I would need to hear it myself . Just my opinion

 

I agree, but that's not the reason that I'm buying one. Larini has a long established race history. If they are telling me I will see a noticeably increase in torque with a flat torque curve across the power band, I'm sold. The tuned sound is an added bonus in my opinion.