Wow , headers and cat delete done

[marc.l]

Well a good result , finished the instal today and was not a fun job to do ! Good news is after rehanging the rear boxs on new rubbers the annoying thump from the back passenger side has gone . It's been making a thud going over bumps for 4 years and mb were never able to get to the bottom of it .
Only thing I don't like is the noise from the front , sounds almost like a blowing exhaust and a lot more metallic than it did before . 99% ***** it's not blowing and it's just because I'm running straight pipes for cats that amplify the sound rather than muffle it .
Other thing to note is no check engine light and wonder if the rear 02 sensors have already been programmed or tuned out . Car definitely runs better and over the return trip is using less fuel .
Pulley on next and tune

Any body else notice the noise with s/steel headers ? It's not awful but may wrap the down pipes to stop it . Noise out of the back I love , deeper and still not intrusive .

Marc
You tube clip up tonight !

 

[Cyclone1]

Marc, it will probably quieten down a little once the pipes have had a few miles of gasses through them, give it a few weeks and see if it changes. Slightly different, but when I had mine secondary decatted, resonator removed and X Pipe installed I too thought it was a bit too metallic, almost like a heat shield was loose, in fact I was that paranoid I took it back to be checked and all was ok. After a couple of weeks the raspyness (is that a word? Lol) disappeared and I now love the sound.....

Jules

 

[marc.l]

Marc, it will probably quieten down a little once the pipes have had a few miles of gasses through them, give it a few weeks and see if it changes. Slightly different, but when I had mine secondary decatted, resonator removed and X Pipe installed I too thought it was a bit too metallic, almost like a heat shield was loose, in fact I was that paranoid I took it back to be checked and all was ok. After a couple of weeks the raspyness (is that a word? Lol) disappeared and I now love the sound.....

Jules

Tbh I have jacked up and checked every joint and manifold connection , twice now and can't hear or see or feel any leaks . Will check in few days when it's all settled down .

 

[Cyclone1]

Would be good to hear it to compare the difference in noise, I think you are fairly local?

Jules

 

[marc.l]

Hi Jules

Yes mate I'm in Nottingham city centre on the river side of the old meadows , the kettle is always on and would be great to see another 55 locally , I have seen a black salon around , what colour is yours ?

 

[Cyclone1]

That's not too far, about 10-15 mins, mine is a black CLS, not E. I'll drop you a pm ref a mini meet up.

Jules.

 

[John]

Did you post a clip?

 

[SavMan]

It's a combination of the primary decat, headers and the specification of the tubing used for the pipes, I originally had headers with secondary decat but kept my primary's and it sounded the same as stock just a little deeper at mid to high RPM.
I then had primary decat with 3 inch pipe and X pipe and experienced the same, you can hear the air and it almost feels as if you have a leak.
I have since gone to long tube headers and the sound is even further amplified.
Do you know what grade and thickness of SS has been used for the pipes?

Large diameter with thin walls tends to have a "tinny" sound

 

[jotter22]

Non hijack question is this primary and secondary cats across the range or just the v8's?

Tony.

 

[SavMan]

Non hijack question is this primary and secondary cats across the range or just the v8's?

Tony.

Depends on the model and year. Most will have a primary and secondary cat, if its a V6 or V8 then normally a set for each cylinder bank.
Not 100% but some of the earlier V6's may have 2 primary but only one secondary (could even be the other way around).
Easiest way to check is look down the rear of the engine bay left and right of the engine you will see an 02 sensor and a primary cat. Then look under the car you should see another 02 sensor and another cat on each exhaust.

 

[marc.l]

Did you post a clip?

Not yet , going to the country in the morning with a helper and hd vid cam

I'm getting used to the tinny noise !!

Hi Paul
, I think he used t304 tube 1.5 mm wall thickness . One thing I'm going to do is wrap the cat delete pipes in manifold wrap to dull it a little . This is really only a short term set up until my long tubes I'm having made are finished . I've had my fabrication guy busy doing a few other projects that are uncar related and so he's well behind .