Fernhurst 'special' exhaust
Fernhurst 'special' exhaust
Author
Discussion

cyberface

Original Poster:

12,214 posts

278 months

Sunday 30th November 2003
quotequote all
Anyone here got one of these?? I may try the Chimaera forum as well, since both ones I've heard have actually been on Chims.

My question being - has anyone noise-tested the exhaust? Basically I want popping and banging and a bit more noise, but I don't want to go over 98 dB so I can still do most track days. Currently a standard Griff 500 is around 88 (?)

GarryM

1,113 posts

304 months

Sunday 30th November 2003
quotequote all
My standard Griff (1996) has been measured at 96dB and 99dB at different circuits so I doubt you will find a sports exhaust that will do what you want below 98dB. Exhausts get louder as they get older so if you have a new Griff yours may be quieter than mine.

jigs

1,840 posts

271 months

Sunday 30th November 2003
quotequote all
Popping and banging may sound great but they are actually indications of an inefficiently tuned engine - caused by unburnt fuel in the hot exhaust - so if you want more get your ECU adjusted to overfuel on the over-run.

Apache

39,731 posts

305 months

Sunday 30th November 2003
quotequote all
He's bloomin right y'know. I have a 'modded' exhaust and it popped and banged like a good un, got a P404 cam etc fitted and a Mark Adams tweak, it does not pop or bang at all and I can put any type of unleaded in without pinking

DustyC

12,820 posts

275 months

Sunday 30th November 2003
quotequote all
jigs said:
Popping and banging may sound great but they are actually indications of an inefficiently tuned engine - caused by unburnt fuel in the hot exhaust - so if you want more get your ECU adjusted to overfuel on the over-run.


Good point.

Big Al.

69,322 posts

279 months

Sunday 30th November 2003
quotequote all
cyberface said:
Anyone here got one of these?? I may try the Chimaera forum as well, since both ones I've heard have actually been on Chims.


OH
But on a 4ltr Chim!

Pops and bangs nicely thank you. It also has a great roar when the right pedal is planted.

Inefficient combustion? Probably, I just like the sound.

Drove a 5 ltr Griff this afternoon at Fernies, my first! Great car, nice and solid with loads of power. Unfortunately didn't have the same sound as mine!

Not sure what mine would read on a meter but a friend of mine mike_e who drives a Cerby, has followed me and he mentioned that mine was loud.

cyberface

Original Poster:

12,214 posts

278 months

Sunday 30th November 2003
quotequote all
Big Al. said:

cyberface said:
Anyone here got one of these?? I may try the Chimaera forum as well, since both ones I've heard have actually been on Chims.



OH
But on a 4ltr Chim!

Pops and bangs nicely thank you. It also has a great roar when the right pedal is planted.


yes, yours was one of the ones I'm talking about!!!

I suppose that I should have my car measured first, and then see how much leeway I have.

What are they like on long journeys?? The only intrusive noise on my car is wind roar from the front of the door seals, currently can't hear the engine at all.

cheeers

cyberface

Original Poster:

12,214 posts

278 months

Sunday 30th November 2003
quotequote all
jigs said:
Popping and banging may sound great but they are actually indications of an inefficiently tuned engine - caused by unburnt fuel in the hot exhaust - so if you want more get your ECU adjusted to overfuel on the over-run.


Yep you are completely correct. And I guess it doesn't really do the cats much good if there's still enough fuel left after the catalyst stages to make a popping noise!!!

However....... it sounds *so* coool!

just trouble

700 posts

275 months

Sunday 30th November 2003
quotequote all
Hello Fella's. I have a Griff 400 and have a "tweeked" sports exhaust and it sounds bloody good. However it does not pop or bang when you ease off the juice. But if yours is the same here is a tip to get the required effect: When changing down apply just enough pressure to the loud pedal ie the weight of your shoe to allow some fuel into the system and hey presto loads of pops and bangs, bloody wonderful. Try it.

>> Edited by just trouble on Sunday 30th November 19:39

RichB

55,125 posts

305 months

Monday 1st December 2003
quotequote all
Apache said:
He's bloomin right y'know. I have a 'modded' exhaust and it popped and banged like a good un, got a P404 cam etc fitted and a Mark Adams tweak, it does not pop or bang at all and I can put any type of unleaded in without pinking
Just to add to the debate I have a 500 with TVR Power 435 cam and Tornado chip and get pops and bangs like a good-un! I can get 20 mpg so all in all quite happy - oh and it's 105 Db but I bought some bolt-on mufflers. Rich...

Painey

534 posts

277 months

Monday 1st December 2003
quotequote all
I've had Fernies perform said modification to the exhaust on my Griff 500 and I love it. It makes a hell of a racket though and they themselves said that it's now comfortably over 100db in noise tests so lots of trackdays are out of the question, which is probably a good thing for me as I can't afford another set of tyres right now.

Also, and this pleased me most, it doesn't seem to have affected the power at all because I've recently had a rolling road session at Austec and the figures of 285bhp/330lb ft were pretty good for an otherwise 'standard' set up.

If you haven't guessed, I'd strongly recommend it!

Cheers - Chris

cyberface

Original Poster:

12,214 posts

278 months

Monday 1st December 2003
quotequote all
Painey said:
I've had Fernies perform said modification to the exhaust on my Griff 500 and I love it. It makes a hell of a racket though and they themselves said that it's now comfortably over 100db in noise tests so lots of trackdays are out of the question, which is probably a good thing for me as I can't afford another set of tyres right now.

Also, and this pleased me most, it doesn't seem to have affected the power at all because I've recently had a rolling road session at Austec and the figures of 285bhp/330lb ft were pretty good for an otherwise 'standard' set up.

If you haven't guessed, I'd strongly recommend it!

Cheers - Chris


Thanks very much - just the info I needed - if it's over 100 dB then I may have to reluctantly forget about it. After all, I'd look like I was taking the piss using the Smart for track days

buster

1,060 posts

305 months

Monday 1st December 2003
quotequote all
I had the Fernies conversion on my '500.

Superb sound, does cause few track db issues tho.

Great value for money.

cyberface

Original Poster:

12,214 posts

278 months

Tuesday 2nd December 2003
quotequote all
OK Plan B. Just spotted that ACT make 'additional' tailpipe silencers for track days. Anyone know whether these would be adequate for getting the dB down on a Fernie special??

No 'what's the point' posts please - I really like the sound of the less-silenced V8, but I also want to do 5-8 track days a year... road driving is its primary use, but I can't afford (or find space for, more like) a separate track day car.

HarryW

15,784 posts

290 months

Tuesday 2nd December 2003
quotequote all
From what I've heard, forgive pun , the ACT tail pipe silencers knock off about 8dBs.
Not sure what figure you'd get from having the baffles removed to know what it'll come down too, I'm sure there will be peeps on here that do though.

Harry

shpub

8,507 posts

293 months

Wednesday 3rd December 2003
quotequote all
cyberface said:
OK Plan B. Just spotted that ACT make 'additional' tailpipe silencers for track days. Anyone know whether these would be adequate for getting the dB down on a Fernie special??

No 'what's the point' posts please - I really like the sound of the less-silenced V8, but I also want to do 5-8 track days a year... road driving is its primary use, but I can't afford (or find space for, more like) a separate track day car.


If you want to do track days then don't mod the exhaust. Some of these exhaust mods will takes the car into 110+ range and there is no way you can then get them down to to the sub 100 or even 98 db you need for places like Goodwood.

Painey

534 posts

277 months

Wednesday 3rd December 2003
quotequote all
I phoned Fernies after having the exhaust mod done to my car and spoke to the service manager, think he's called Brian, and he said it was "definitely over 100db, but probably not more than 105db". So if a silencer that you can add for track days will reduce it by 8db then you might be OK.

If in doubt, give them a call as I found them very helpful.

Cheers - Chris

RichB

55,125 posts

305 months

Wednesday 3rd December 2003
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I know Steve has strong opinions about this subject but fact is I have a straight-through exhaust and measured 105 at Goodwood and was ok with my Merlin Mufflers (all the chap said was that I was at a tad under 100) At Bedford I was initialy red-carded on the static test but I got let on no problems after the drive-by test without my bolt-on mufflers Point is that it's not a case of back and white, if you fancy the pops and bangs then there is a way round it for track-days. Rich...

shpub

8,507 posts

293 months

Wednesday 3rd December 2003
quotequote all
The only way to measure this is with a dB meter. For every case that says I got away with it I know of a couple that haven't. Also bear in mind that the readings can vary by several DB depending on atmospheric conditions and that some circuits take the readings at a higher rev point. Goodwood measure at 3/4 and not 2/3rds. Result is that cars are often about 2-3 db higher at Goodwood. Let's say the car is 105... go to Goodwood and that will be 107-108 cos of the higher revs. The weather is warmer and that adds another 1 dB. Add muffler to remove 8db and you are still no where near 98!

The problem is that unless you are well under, there is a big risk of getting to a circuit and then finding you can't play and all the costs etc down the tubes.

As the noise regs will continue to get tighter, this problem is only going to get worse not better.

In the end it is your choice and if you go down the route track day mufflers can help so are worth getting.

RichB

55,125 posts

305 months

Wednesday 3rd December 2003
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I hear what you are saying Steve! Just about... going a bit "Mutt 'n Jeff" these days, must be that car of mine Rich...