coldhammer

BlownV8

Straight pipe all the way back to the exhaust tips with turbo down pipes. The turbos quiet it enough that you don't need any mufflers. That along with the Race Horse intake will wake your car up and make it sound amazing.

coldhammer

euphoriaDSM

It doesn't. Search...

coldhammer

Already searched. "I was running open downpipes with no mufflers just to test it for 20 minutes after the install and it was obnoxious inside the cabin with drone and resonance"

PrecisionEngine

During your test, did the exhaust exit beneath the car, or behind the car. Exhaust exiting beneath the car will cause what you describe. However, properly piped exhaust, exiting behind the vehicle will almost eliminate the drone. These cars are very quiet in stock form.

As for searching, there's plenty of threads on this forum documenting the affects of different types of non-OEM exhaust systems.

Ed954

I currently have mufflers deleted, but we want to put them back and do the QTP cutouts instead. The installer told us that it will improve the sound slightly. I love the muffler delete option, but sometimes wish the car would sound even louder. No drone with muffler delete.

coldhammer

I was just pasting what someone else reported. I havent done it myself. That said i have rode in several different cars that had muffler deletes and they all had droning issues. Seems to be split down the middle on droning with muffler delete from other postings. I may try it out without muffler first just to see for myself.

Is everyone using the stock pipes or are you guys replacing with larger exhaust piping?

carlsturm

If you want to make changes incrementally you may want to start with the muffler delete. Sound lots better, authoritative when you get on it but relatively quiet when you're just cruising.

Any muffler shop can remove the muffler and weld the stock tips back on. Cost me $75 a few years ago. good-luck.

earl3

Anyone making downpipes for 65s these days?

PrecisionEngine

From your post, I was under the impression that you had actually heard what one sounds like in person. Unfortunately, recordings are just not representative of what the car sounds like. Further, exhaust sound is very subjective, and everybody perceives tone, loudness, and drone differently. However, I will try to be as objective as I can.

I've owned two of these cars. I love them for their quietness, comfort, and class, but yet their ability to growl to life once you stand on the pedal. I was too underwhelmed with the exhaust in stock form.

The first car received muffler deletes. However, I did not just cut the stock mufflers off the car. To me, that's a cheap hack way of getting the job done. Instead, I cut open the mufflers. To my surprise, the mufflers were a straight-through design. I.e., there's no baffles or restrictions inside. They are simply a straight piece of pipe full of holes, wrapped with steel wool. I removed the drilled pipe, replaced it with a non-drilled piece, and welded the muffler back together. The car sounded good: no drone, no difference at all in cabin noise, unless you were standing on the pedal. It was enough for me at the time. And the car was still under warranty, so I didn't want to install downpipes.

However, on the second car, having learned a lot with the first one, I opted for downpipes. Having learned that the mufflers were of a straight through design, I was not going to mess with them this time around. (do some research on straight-through design mufflers, lots of them flow better than straight pipes because of the boundary layer they create inside the holed pipe.) Further, there's a significant performance benefit to downpipes. Having the car on the lift, I evaluated whether I would change the remainder of the exhaust on the car to 3". I chose not to because the car already has 2 7/8" piping from front to back, including inside the mufflers. The downpipes sound even better than the muffler delete: no drone, no difference in cabin noise unless you're accelerating quickly. Although I would like a bit more exhaust note when horsing around, I enjoy being able to get in the car and drive 3-400 miles without any sense of modification. Coupled with the fact that there's no restriction in the mufflers, the exhaust will stay as it is.

NOTE: the only downside to downpipes is that you get a bit of exhaust smell at stop lights with the top down. The smell is just like that of an old '60s car with a carburetor: rich, pungent smell of raw fuel. I believe that the factory tune richens the AFR at idle to keep heat in the cats. However, without cats, you get that smell. One day I will get around to tuning the car and hopefully removing that smell.

This is as concise and descriptive as I can be.

coldhammer

@precisionEngine - thanks for the informative write up. My intial goal was to put in a set of speedriven downpipes. However they are no longer in business and (correct me if you know otherwise) there is no other source of downpipes atm. I next looked into doing a mandrel bent setup but the only shop around here that did mandrel bending shut down a couple of years ago. Did you buy your downpipes or make them?

PrecisionEngine

I bought mine from SD. As you noted, they are no more. However, I was not very impressed with SD's work on my particular set of downpipes. They required some massaging to make them fit properly, and the welds were not the greatest. But hey, they function and they're wrapped so nobody will ever see it.

Honestly, I would call Shardul or Eurocharged and ask them to make you a set. I know both have done it for other members in the past. Kleeman used to make a set as well, but I think they were swallowed by Weistec. Could try them as well.

StirlingMoss722

Brandon @ Kleemann in Colorado can make you a set of downpipes and fully install for less than $2K. ;-)

Ekselent

Here is the best setup. Titanium 3" exhaust systeem. Only 19 lbs.

StirlingMoss722

@ Ekselent

Very Nice!

What was the price on those?