Silverstone Performance Exhaust

[thegreengoblet]

I have a sports exhaust fitted but my Cats have started knocking. Decat with sports back box is going to be too loud. So I'm looking at the SP Exhaust system. Anybody got the complete system fitted? What does it sound like compared to a sports exhaust system (with Cats)?

[NeilV70R]

I haven't got an SP system, but I was at TorqueRVT a couple of months ago and Ian had just fitted an SP system to a Cerb. He thought it was "effin" expensive, but sounded "effin" awesome. In his words - "just like a pre-cat Griff when ticking over".

[thegreengoblet]

Thanks Neil

Yeah, it's the price that's putting me off at the mo - £100 for a linked decat pipe plus £350 for a standard back box vs £1k.

[Steve_T]

Another option would be ACT cherry bomb decats. I think someone here has them fitted - Mr Freefall?

[Mr Freefall]

Steve_T said:

Another option would be ACT cherry bomb decats. I think someone here has them fitted - Mr Freefall?

I do...

Just replace your cats with these, and your good to go. I had them with the Sport Silences and they were fine...

£200 I think, might have to add vodka to that however...

Mr F

[Work-Shy-Wanabe]

NeilV70R said:

I haven't got an SP system, but I was at TorqueRVT a couple of months ago and Ian had just fitted an SP system to a Cerb. He thought it was "effin" expensive, but sounded "effin" awesome. In his words - "just like a pre-cat Griff when ticking over".

Think that was my car. Its not cheap at all but its qaulity.

[HarryW]

Work-Shy-Wanabe said:

NeilV70R said:

I haven't got an SP system, but I was at TorqueRVT a couple of months ago and Ian had just fitted an SP system to a Cerb. He thought it was "effin" expensive, but sounded "effin" awesome. In his words - "just like a pre-cat Griff when ticking over".

Think that was my car. Its not cheap at all but its qaulity.

If I'm not mistaken you have a high spec rebuilt lump that's a little bit more juicy than standard. That would account for the nice engine note, there is a world of difference between just an exhaust note and a sweet engine imho.

[Full SP]

HarryW said:

If I'm not mistaken you have a high spec rebuilt lump that's a little bit more juicy than standard. That would account for the nice engine note, there is a world of difference between just an exhaust note and a sweet engine imho.

This is absolutely false. The SP system sounds like this on ALL Cerbs. There is a variation from car to car, as you would expect, but the basic character is the same.

Edited by Full SP on Thursday 13th September 21:23

[thegreengoblet]

Mr Freefall said:

Steve_T said:

Another option would be ACT cherry bomb decats. I think someone here has them fitted - Mr Freefall?

I do...

Just replace your cats with these, and your good to go. I had them with the Sport Silences and they were fine...

£200 I think, might have to add vodka to that however...

Mr F

Cheers for that.
So how much louder compared to the Sports Exhaust with Cats?

[thegreengoblet]

Full SP

Why is your exhaust system so expensive? And how would you persuade me to buy one over standard bits and bobs?

[HarryW]

Full SP said:

HarryW said:

If I'm not mistaken you have a high spec rebuilt lump that's a little bit more juicy than standard. That would account for the nice engine note, there is a world of difference between just an exhaust note and a sweet engine imho.

This is absolutely false. The SP system sounds like this on ALL Cerbs. There is a variation from car to car, as you would expect, but the basic character is the same.

Edited by Full SP on Thursday 13th September 21:23

Not saying an exhaust doesn't improve the sound of a car, I don't necessarily agree with it being 'false' to say a well built and tuned lump does sound different and imho better though.

[BCA]

FullSP, any chance we can "test" a system long term, much in the same way I believe MadBadger did with your wheels?? It could be pretty advantageous to our grass roots motorsport commitments. worth a try eh?

[FarmyardPants]

I've never heard this mentioned on exhaust discussions, but here goes..

Sound-wise, if you have twin rear silencers (eg ACT), you effectively have two independent notes being played, each side being independent of the other (assuming no link decat), so they make a chord, like two trumpeters in a mini orchestra.

Whereas if you have the std (or SP) rear box, the two sounds are merged prior to exiting the box, so that there is only really one 'voice' coming out, even if it is via two holes.

So although I think the SP and std boxes sound great, I've noticed times when the dual note has sounded sublime, eg when giving it some beans in the fast lane with those concrete walls in the central reservation. There's a harmony with low frequency beats (for the technically minded) which is quite surreal and IMO the best sound of any engine short of a spitfire at airshows.

Anyone else had that, or am I just missing my cerb too much?

[Steve_T]

They would make a chord if the exhaust system differed on either side, or the banks of the engine somehow differed. They don't so I don't go with your hypothesis. I agree with Harry that the engine sound could differ depending on engine build - for instance different duration cams would alter the sound because they alter revs at which the exhaust is a tuned length.

Steve

Edited by Steve_T on Friday 14th September 09:44

[Mr Freefall]

thegreengoblet said:

Mr Freefall said:

Steve_T said:

Another option would be ACT cherry bomb decats. I think someone here has them fitted - Mr Freefall?

I do...

Just replace your cats with these, and your good to go. I had them with the Sport Silences and they were fine...

£200 I think, might have to add vodka to that however...

Mr F

Cheers for that.
So how much louder compared to the Sports Exhaust with Cats?

Hardly any, until you hit 4500-5000rpm with the pedal nailed, then there is a real nice rasp to it all.

My Zorst started to fall apart, so I had a 2.5 bore made from the sports silencer (2.0&quotonwards with 3" tails, in stainless, and it read 101bd at 4000rmp...

Mr F

[madbadger]

BCA said:

FullSP, any chance we can "test" a system long term, much in the same way I believe MadBadger did with your wheels?? It could be pretty advantageous to our grass roots motorsport commitments. worth a try eh?

Not me. I bought my wheels.

[itsallyellow]

Im running a full SP system on the race car!

[ro_butler]

thegreengoblet said:

Mr Freefall said:

Steve_T said:

Another option would be ACT cherry bomb decats. I think someone here has them fitted - Mr Freefall?

I do...

Just replace your cats with these, and your good to go. I had them with the Sport Silences and they were fine...

£200 I think, might have to add vodka to that however...

Mr F

Cheers for that.
So how much louder compared to the Sports Exhaust with Cats?

It isn't. It is quieter.
My SP exhaust without cats is quieter than my old sports exhaust with cats.

My car is now much quieter (better IMHO) on the motorway but actually has a nicer exhaust note when you 'go for it' than my old sports system. It also gives you a decent chance of getting on a track day.

[dempsey]

I've got the SP back end with linked decats courtesy of Trackcar.

Nice sound, not too loud but nice and gutteral over 3500rpm.

Good looking 3" tail pipes.

Measured 101db at Bedford; then (with completely the same setup) 98db
at Brands at the recent evening track session. I've always thought these
sound measurements had a random element about them (note also that all
sound meters say their accuracy is +/- 1.5 db which makes a bit of a
mockery of the limits that are applied).

[BCA]

madbadger said:

BCA said:

FullSP, any chance we can "test" a system long term, much in the same way I believe MadBadger did with your wheels?? It could be pretty advantageous to our grass roots motorsport commitments. worth a try eh?

Not me. I bought my wheels.

Ah my mistake.. im sure someone tested them for free..?