100 cell cat
- Thread starter angry
- Start date
Angry, yes I have 100 cell cats on and get on at bedford, Castle combe and Goodwood. You have selected receive no emails on the mail system so i can't mail you back via the pm!
So in public, here is the answer:
The mufflers make a difference as do the cats as does the temp of the system when tested, I also have some fancy Cargraphic tips that have perforated insides and I suspect a small amount of sound deadening material, but it must be so thin that it makes little difference.
My system is:
Std headers, used to have big bore NGT cargraphic headers, not any more, from headers back full NGT system including boxes and 100 cell cats, lovely sound the best of all systems in my opinion, plus these tips.
The sound as above has been tested at 105db on the nose, hot, at CC, Bedford and Goodwood. For quiet days I fit a set of aux mufflers from Merlin which bolt on via a length of stainless pipe with a flange on the end in the place of the tips, this brings me down to 99db hot tested at CC.
Hope that helps
All the best
John
So in public, here is the answer:
The mufflers make a difference as do the cats as does the temp of the system when tested, I also have some fancy Cargraphic tips that have perforated insides and I suspect a small amount of sound deadening material, but it must be so thin that it makes little difference.
My system is:
Std headers, used to have big bore NGT cargraphic headers, not any more, from headers back full NGT system including boxes and 100 cell cats, lovely sound the best of all systems in my opinion, plus these tips.
The sound as above has been tested at 105db on the nose, hot, at CC, Bedford and Goodwood. For quiet days I fit a set of aux mufflers from Merlin which bolt on via a length of stainless pipe with a flange on the end in the place of the tips, this brings me down to 99db hot tested at CC.
Hope that helps
All the best
John
leesweeney
New member
I have Dansk 100 cell cats and RSR mufflers and was thrown off Croft trackday having been tested at 106db at 4000rpm.
Worth it for the sound though.
I heard a 993 with the Dansk 100 cell cats and standard mufflers and it sounded great and was defintily much louder than standard but definitely a lot quieter than mine.
Cheers John.
I have de-cat pipe at the moment,with standard boxes,i think it sounds fantastic.
It is 102db at 4000rpm.
I am a regular at the Ring and there is talk this year of them being very strict on the existing 95db rule.
They have not been strict until now,but i am just looking at the options.
So i guess even with 100cell cats i will be over 95dbs.
Dan
I have de-cat pipe at the moment,with standard boxes,i think it sounds fantastic.
It is 102db at 4000rpm.
I am a regular at the Ring and there is talk this year of them being very strict on the existing 95db rule.
They have not been strict until now,but i am just looking at the options.
So i guess even with 100cell cats i will be over 95dbs.
Dan
100 cell cats with std boxes will be over 95db's the scale is logarithmic, you could try the extra mufflers from Merlin : http://www.merlinmotorsport.co.uk/EXHAUSTS-Merlin-Silencers-Silencers/c223_228_230/p1576/MERLIN-MUFFLER-4-DIA-X-8/product_info.html but will the need to get fabricated pipes and cones from the mufflewr to the end of the box -c cost me £50 for two adaptors from my friendly engineering / welding shop in Gloucester.
Std boxes plus 100 cell cats plus aux silencers would prob come in under 95db, the other bonus is you test w/out aux mufflers and if it passes bingo, if it doesn't then on go the boxes. Castle Combe will always sound test you if you turn up on a track day (any track day) especially if at say 09:30 when it has started but they still have the sound meter to hand. FOC and even if you are not on the track day, they are top blokes, just say you are booked on a quiet day in the future and want to check your car out, I have done this and found them extremely helpful.
Obviously no use if you live miles away but maybe your "local" circuit will oblige, def better than turning up at the ring and not getting on.
Lee - the RSR's (std silencer with the baffles cut out) are a less sophisticated solution than the Cargarphic and other sports mufflers, I had RSR's before I went to cargraphic and with RSR's and the std cat I was 101 - 103db and needed aux cans with no power benefit!
Cheers
John
Std boxes plus 100 cell cats plus aux silencers would prob come in under 95db, the other bonus is you test w/out aux mufflers and if it passes bingo, if it doesn't then on go the boxes. Castle Combe will always sound test you if you turn up on a track day (any track day) especially if at say 09:30 when it has started but they still have the sound meter to hand. FOC and even if you are not on the track day, they are top blokes, just say you are booked on a quiet day in the future and want to check your car out, I have done this and found them extremely helpful.
Obviously no use if you live miles away but maybe your "local" circuit will oblige, def better than turning up at the ring and not getting on.
Lee - the RSR's (std silencer with the baffles cut out) are a less sophisticated solution than the Cargarphic and other sports mufflers, I had RSR's before I went to cargraphic and with RSR's and the std cat I was 101 - 103db and needed aux cans with no power benefit!
Cheers
John
graemeho
New member
The 100 cell cats will mean that the emissions are higher as there are effectively less catalyst for the exhaust gases to pass through. Remap won't improve this I'm afraid. How far over was it? If it was marginal then a run to get the car really hot on the way to the mot might just bring it in.
Cheers
Graeme
Cheers
Graeme
Flightrisk
New member
Had a similar experience moving to 200cel cats. These engines are now getting on a bit it in age and mileage so are going to be producing more emissions anyway, this combined with your new cat being only a quarter of the number of cels compared to standard is going to be problematic. A remap could be used to lean off the emissions at the tested revs but that is not exactly a longterm solution.
Something that helped emissions on mine was having a Terraclean, it might just tip the balance if your fail was marginal:
http://www.porscheclubgbforum.com/tm.asp?m=797948
Something that helped emissions on mine was having a Terraclean, it might just tip the balance if your fail was marginal:
http://www.porscheclubgbforum.com/tm.asp?m=797948
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