Hi all,

My HKS Hi-power silent exhaust is starting to bother me (and my other half!). It has become louder and boomier over the past 6months. It doesn't sound like what it used to. Am I going mad or can an exhaust change its sound over the years with use?

I've had the HKS for around 4 years now (from new with decat) and probably done around 40k miles with it. Last year I started to notice the change in sound + I was bored, so I chopped the chamber off (gutted it). It sounded awesome for a while, but now it's not the same, it doesn't have the growl that i loved

I have not checked for any holes or leaks yet.

Can somebody enlighten me please?

 

I used to have this system...it drones to feck. Its made of mild steel and prone to rot. have a look underneath...it may be holy

 

Not an expert opinion in the slightest, but Vixen's HKS rusted through a couple of years back, causing similar issues, I seem to remember. Can't be more specific, I'm afraid, but I would suggest having a look for holes.

It became garden ornaments after removal and a quick polish later.

 

Didnt know it was mild steel, i just assumed that after market meant stainless. i which i had done my idea of hammeriting it before fitting.

if it has popped a hole there is no reason why it cant be re welded.

and yes an air leak will change the noise.

 

I blew a weld point on the Col de Turini a few weeks back. The point where a hangar was welded to the tubing just blew out, leaving a 10p sized hole. Car sounded like a knackered transit van until I patched it with jubilee clips and a can of coke.
Fuel economy went way down too.

 

Time to change your Hi Power 'SILENT' exhaust

 

Mines about the same age as yours, Mytse. Will be interesting to see whats playing up!

 

I think you are confusing the 'Hi-power silent' with the 'Hyper'.

The Hyper had mild steel pipes and stainless silencers whereas the Hi-Power silent is completely stainless IIRC.

I have never seen the point of the Hi-power silent as the bes thing about the Hyper was the noise.

 

Mine is an all stainless steel system. Not to be confused with the 409 ones.

2/3 months ago when I had the car serviced, everything underneath looked ok.

I found this HKS mellow out, are the yanks making sense?

@nomadicS2k, How does your HKS sound now after a few years?

 

i've had my HKS for several years mytse - can compare if you're knocking about? you haven't fitted induction or maybe got an issue at that end have you?