I only have one fairly short impression for the new sound and volume levels. I took the car for the 15 minute test drive and then pulled the pipes to send off to get them re-coated with the ceramic shiny stuff.

The sound at idle is now lower pitch, so more bass sounding. It's certainly quieter than the sound after the ruptured baffle and I think quieter than the original CR1 muffler. It's not too quiet though, so about right for a Cobra.

The sound at WOT, well it still sounds V8 healthy and I doubt I could pass the sound check on the Laguna Seca back/uphill stretch with the throttle down. But it sounded quieter than the straight pipe I had. On the test drive, I was on country roads so I don't yet know how it sounds with the exhaust bouncing back off concrete barriers. That's the true test for the daily commute driving ;)

I do like that the mufflers run cooler now. After the test drive, I was able to put my hand on the muffler momentarily without getting burned. I would never of attempted that with the old mufflers. Even getting close to the old mufflers right after shutdown could raise a blister. The external part of the muffler was not too hot even though the mild steel before and after it turned blue.

Final chapter in sidepipe rattle
 

I thought I'd post a final chapter to this story just in case anyone is interested. Here's how the sidepipes look after final coating:

http://www.clubcobra.com/photopost/d...0834_-_web.jpg

I had the pipes coated with Cerakote Chromex by a local company that is a certified applicator of this product. They came out great and are brighter/shinier than the JetHot coating that was on them prior. I'm very happy with the finish so far.

After driving the car with the new mufflers for a couple of months now, here's my impressions. The thing I like most about the new mufflers (beyond the extra 30+ HP) is that they run much cooler than the old ones. They run cool enough that I don't feel the need to remind everyone who I take for a ride to watch the muffler on exit. The double wall SS construction is far superior to the mega-heat radiating single wall steel mufflers.

I like the new sound as well. They have more of a bass sound, that is lower pitched. More like a big block Cobra has. Unless I tell people otherwise, they assume it has a big block from the bass exhaust note.

As to loudness, they are louder than the original CRL sidepipe muffler but not by much. They are quieter than the equivalent sidepipe glass pack muffler. I don't need ear plugs when driving. I can hear the stereo fine, that is until a speed of 65 is surpassed, but this is just wind noise, not exhaust loudnesses.

For you budget minded guys out there, these mufflers aren't the cheapest option. At about $215 apiece, they are on the pricy side, but save yourself just one snakebite and the extra cost is really worth it ;) Also, given the SS construction throughout, I'd bet that these won't rot out like the old ones. :3DSMILE:

As a builder for more years than ill admit , we've been using different mufflers for at least 30+ years. Dyno'd many times from CARB'd 302's thru stroked 427's Minimum HP gains over CR's stock pipes is: 42 to 48 HP. EVERYMOTOR UP in Cubes was exponentially more!

Forget the "Band Aid" repairs, forget about the money you wasted on "Jet-Hot", CHANGE THE MUFFLERS, richen up your fuel by 2-5 percent and cruise very Happily ever after!
( don't believe me? DYNO your "Little Snake". )
DV

(IF YOUR PROPERLY TUNED ADD 1-2 degrees in timing!)
PS. We did and still "did" use lifetime warranty Bullits from J.C. Whitney, (build by Arizona competition Exhauts) Never had to warranty one yet! $30.00 a side!

Original CR1 Side Pipes
 

Hey DV, I have this issue with my side pipes, is this modification something you could help me with? this repair is more than I can handle, I could ship or drop off my side pipes, if so please let me know your hourly rate, or if you could point me in the right direction, I live in Pinckney, MI. any input would be much appreciated. Thank you, Mike

This fix works, did it two years ago, still no rattle. Don't drill through inner pipe.

My pipes are so loud they hurt my ears. I want a powerful thumping sound that does not hurt my ears but shakes my gut with cottony edges to the sound.

Will these JC Whitney bullets make a sound like that? I don't mind spending some bucks on it but I want a reasonable level of sound without losing too much hp. and I don't want to do it more than once.

JC Whitney bullets will be a lower cost option, but I'd go with the Flowmaster Slimline side pipe mufflers. Equal or more power and much cooler than single wall side pipe mufflers - cool enough that you won't need to remind everyone to watch the muffler on exit.

FM Slimline mufflers are slightly louder than original CR side pipe mufflers, but quieter than equivalent side pipe glass packs. Many prefer the sound as well - lower-pitched, more bass sound, that some mistake for a big block, even with a SBF. There's a long thread here ( http://www.ffcars.com/forums/17-fact...slimeline.html ), including a link to dyno testing (with sound level measurements as well) - see post #95.

https://www.youtube.com/watch?v=ZZJ1...ature=youtu.be

Thanks Cycleguy! I'll look at that.;)

Another video - this one of FFR side pipes with Flowmaster Slimline Mufflers in place of FFR mufflers.

https://www.youtube.com/watch?v=_BsQtkuzJdE

Conclusions from video:

• Much quieter at cruise, allowing normal conversation.
• Still sounds good on heavy throttle application.
• Worthwhile upgrade for driver comfort and hearing.

Is this a small block motor? I want it to shake my guts like Kinser's outlaw sprint car.;)

No, it's a Coyote.

SCOTT SPENCER COYOTE-POWERED COBRA

Scott Spencer's Factory Five Mk4 Cobra - DPBRANDS NEWS

Pipes
 

CC5TO. Probably. Baffle coming loose,mine has same sound at idle on pass side. Goes away at speed not worried right now . There is several threads on subject look them up , hope you get it fixed. Bulldog.

Well done!

As I look at the beautiful, but restrictive CR 1 side pipes in my garage to be installed and think "I need to cut these apart & then refinish them" to get real performance, I really pause. Then I think about the first time my wife gets a "snake bite" getting in and out and the screams of agony (from me- not her, as she yells!).

My question is, has anyone here installed an underbody exhaust system on a CR? I have seen a couple of examples of FFR cars converted. They used the oval style mufflers to keep a lower profile.

I would have to install heat shields under the body at the muffler locations. But getting around (or under) the rear end could be tricky with the gas tank. My first ride in an original 427 when I was 17 was a non-SC version. But I still remember the exhaust was pretty raspy even with the rear exiting exhaust. And that was compared to my 55 Chevy with a 2 1/2" exhaust exiting under the car in front of the rear axle (huge drone at certain speeds).

I also would have to use different exhaust headers on the 5.0.

Suggestions?

http://www.clubcobra.com/photopost/d...Sidepipes2.jpg My Existing pipes:

I might like to put the muffs under the car but since the floor attaches to the bottom of the perimeter frame rail its too low. I'll have to do some sort of side pipe. Proably the flowmasters that are designed for the side application.

I used 1 3/4 self tapping screw with hex head so easier to tighten up, put 2 on each side worked perfect