Exhaust

Sully-K · September 18, 2016

Hi guys,

I know this has been covered many many times, however can anyone recommend a place to get an exhaust (cat back) for the ISF. I am mainly looking for places up north.

Warrington guy · September 18, 2016

Got mine from cobra sports in Sheffield . Great sound

Sully-K · September 18, 2016

If you don't mind me asking how much did it cost (can pm me if needed) and did you get the same shape as the tips that come as standard?

GibletPH · September 18, 2016

I had a full system with secondary cats removal done by STG Performance in Wakefield. Also have a valve fitted which makes it noticeably louder. Stuck with stock tips and went for some small backboxes but I'll be calling him tomorrow to get a price on having them changed to something bigger. Prefer the stock tips as it keeps it looking OEM.

If you are ever around Leeds then give me a shout and I can meet up if you want to hear what mine sounds like.

Sully-K · September 18, 2016

Mate that is awesome thank you. I am from Bradford so round the corner from you and I drive past leeds to and from work so I will definitely take you up on the offer.

Peter P18 · September 19, 2016

Good to see some forum spirit with owners trying to help each other out.

Just be mindful that most circuits in the UK are quite strict in terms of noise restrictions. I am a little sad my current system won't allow me to go on track given the cars clear ability in this respect. Will hopefully address that with H&S once I get my headers installed.

May need another revision after we go the supercharger route! Lol. That looks like larger headers and a full 3' exhaust (currently 2.5').

Best of luck getting something organised though. Does need more noise to really appreciate that V8 burble!

Grey One · September 19, 2016

As an aside, my Missus said a neighbour complained to her the other day about the noise my ISF makes on early morning start-up (0600-0700). I have an HS cat back fitted and try to slip the car straight into gear on start-up to avoid the very noisy initial idle sound (takes about 30 secs to quieten down). If they persist I will get the noise level tested to make sure I am in legal limits (the was supplied to me by Lexus with the exhaust so I presumably have some comeback if there are any issues).

Whilst I fully get not liking noisy cars/bikes, especial during sleeping hours, I do try to minimize the noise, but if the car is in road legal sound limits (which it should be) there isn’t anything they can do unless they can prove malicious intent etc...

Has anyone else had this issue with their HS system?

Peter P18 · September 19, 2016

Hi James,

I do the exact same thing when I cold start at my parents house!

Even shifting straight to 'D' emits some noise, but 100% quieter than leaving it the 30-40 secs to quieten down on it's own.

Can't see yours being that different to mine chap? When H&S tested mine pre-X pipe, it was 92.8db at idle, then 118db if blipped.

Not sure what the law says on this, but don't see how anything below 100db would be an issue??

mrfunex · September 19, 2016

I've got a H&S cat-back on mine. Had it noise tested at Goodwood and it was 102-103dB at 5000rpm (roughly 3/4 max rpm at 1m & 45deg from the tail). Noise limit at Goodwood is 98.. :-(

Silverstone has a 105dB limit...

How's the X-pipe treating you Peter? Now it's settled down is it much quieter than before you had it?

Peter P18 · September 19, 2016

Hi, yes, I'm finding it quieter than it was before. Hoping now I've got the article out the way, I can arrange another dyno run to see how it compares to the last pre X pipe run it had.

Performance was the main consideration as far as the X pipe, but it has made a noticeable difference to normal driving.

Now I'm on the verge of adding PPE headers, it'll be interesting to see how it turns out.

I'd like to do more track days with the car, but that may require a complete re-think with the exhaust. The fact RR-Racing are looking at different headers from PPE, could mean the exhaust needs to be changed to 3' from the current 2.5' setup. If so, I'd like Ian to develop a system that keeps the db levels under 100.

Warrington guy · September 19, 2016

Well worth adding a good intake to get the V8 to sound good too

Grey One · September 20, 2016

Well I did some research online last night trawling through various forums etc., and what I found wasn't good news, but also confusing:

- the consensus seems to be that the limit for exhaust noise is 82 decibels

- you are not allowed to put an exhaust on a car that creates more noise and power than stock

On the other hand, you have businesses like Milltek, H&S etc. churning out systems that are patently in breach of these laws, so does the average petrolhead stand in all this?

Some links on the above as follows:

- http://www.dft.gov.uk/vca/fcb/cars-and-noise.asp

- http://www.walesonline.co.uk/news/wales-news/police-crackdown-deafening-car-exhausts-1905480

- https://www.nidirect.gov.uk/articles/modified-cars-what-you-need-know (see 'Exhaust systems at bottom of page)

GibletPH · September 20, 2016

With regards to the law, my exhaust passed an MOT with the valve open so no issues there, I've not been pulled over for it by the plod either. From what I have read over the years it is a very grey area when it comes to actual enforcement.

I've owned cars with much louder exhaust systems before without any issues.

Oh and the increased noise at startup is there to warm up the cats. This can be mapped out with the remap available across the pond.

Grey One · September 20, 2016

Hi Chap - yes, just putting it 'out there' for feedback and discussion. As I said, it seems to be a very grey area and evidently very few people seem to get bothered by it, but it would be good to have more insights from people about whether this is all a false flag or if not what people's experience of it is.

Cheers

Peter P18 · September 20, 2016

Cheers James.

May be able to remap sooner than you think!

Pretty sure once Rafi and Simon have bench read my ECU next month, they can send the maps to me to upload to the OBD II reader I will be getting, and I can then remap other IS F's as well.

Exciting times!

Grey One · September 20, 2016

46 minutes ago, Peter P18 said:

Cheers James.

May be able to remap sooner than you think!

Pretty sure once Rafi and Simon have bench read my ECU next month, they can send the maps to me to upload to the OBD II reader I will be getting, and I can then remap other IS F's as well.

Exciting times!

Hi Peter - great stuff :)

Looking forward to hearing more...

Matrixxxx · October 5, 2016

I would have thought 85dBA would be a limit as above this you are supposed to wear hearing protection if you are working next to noisy equipement?

I did start to modify a spare exhaust, but have stopped , as i now think I like the stock exhaust , especially after a 12 hour drive from john o'groats to York Via fort william , i was in sport mode for at lease 4 hours of the drive :) if you want noise the 2nd stage induction roar is spot on.

markovanb · October 5, 2016

I was at the main dealer a few weeks ago, having the n/s exhaust back box hanger that is bolted to the car changed, i have already changed the o/s rear ex box hanger last year, has anyone else had this problem with them rotting through?

Also if anyone is changing their original back boxes for aftermarket items please let me know if you are interested in selling them,as it seems most of you leave them behind at the fitting garages i have read previously,

as the main dealer says the mounting bracket on one of my back boxes is not too clever and says box would need replacing in 12-18 months, so i will be looking for some original boxes soon it seems as i think the car is loud enough now, without the extra noise that replacement boxes seem to be making

Thanks

Mark

Matrixxxx · October 5, 2016

I got a spare set from H&S,

markovanb · October 5, 2016

Thanks Matrixxxx but i want the original Lexus back boxes not replacement after market items, as after market items seem to be too noisy for me from what i have read on here