Ponetial new owner.... pre cat v's late 500's
Discussion
Hi,
I am thinking about purchasing a Griff and have done a bit of research on the different Griffiths out there.
One thing that always seems to crop up is the noise of the Precat cars!
I was just wondering what the technical differences were that attribute to the noise differences. Is its merely (as the name suggests) the pre cats in the manifolds? if so can you not just remove them from the later 500s for the same sound? or is there more to it (as I suspect!) than that, mots etc aside?
Thanks
Andy
I am thinking about purchasing a Griff and have done a bit of research on the different Griffiths out there.
One thing that always seems to crop up is the noise of the Precat cars!
I was just wondering what the technical differences were that attribute to the noise differences. Is its merely (as the name suggests) the pre cats in the manifolds? if so can you not just remove them from the later 500s for the same sound? or is there more to it (as I suspect!) than that, mots etc aside?
Thanks
Andy
rsnissan said:
Hi,
I am thinking about purchasing a Griff and have done a bit of research on the different Griffiths out there.
One thing that always seems to crop up is the noise of the Precat cars!
I was just wondering what the technical differences were that attribute to the noise differences. Is its merely (as the name suggests) the pre cats in the manifolds? if so can you not just remove them from the later 500s for the same sound? or is there more to it (as I suspect!) than that, mots etc aside?
Thanks
Andy
Slightly confusingly there are two use for the phrase 'Pre Cats' The 'pre-cat' Griffs (4.0,4.3,4.5) have 0 cats in them having being registered before the 1993 cut off (in this case pre-cat refers to the fact they were built before the cat laws came into force). The later Griffs i.e the 500s have 3 cats - a main cat and 2 pre-cats in the manifolds that are there to cut warm up emissions. (in this case pre-cat refers to the 2small cats in the manifolds that are before the main cat)I am thinking about purchasing a Griff and have done a bit of research on the different Griffiths out there.
One thing that always seems to crop up is the noise of the Precat cars!
I was just wondering what the technical differences were that attribute to the noise differences. Is its merely (as the name suggests) the pre cats in the manifolds? if so can you not just remove them from the later 500s for the same sound? or is there more to it (as I suspect!) than that, mots etc aside?
Thanks
Andy
The pre-cats in the 500's can be removed easily but do not really add anything to power or noise unless the main cat is removed, this though causes issues with MOT time although there are workarounds
If you want a 500 with near pre-cat sound then most people don't bother mucking around with removing the cats but opt to have the exhaust silencer modified (so called sports exhaust) as its cheap and easy. Although be careful who you have perform mod - having had 3 for these done I can confirm their not all the same, most people seem more than happy (including me) with Offords (near Cambridge) Cherry Bomb conversion (that actually doesn't contain cherry bombs but thats another story
) as once bedded in it gives lots of pops and bangs 
on the overrun once you know how to provoke it.Edited by RIP_puffsorted2 on Wednesday 17th September 18:56
The 500s have a diffent shape manifold (big bulgy bits for the cats) so even if you take all the cats out, it won't sound the same as a pre-cat.
Having had both I always thought that a decatted 500 sounded to be doing twice the rpm of a pre-cat... nice, but not as nice as the original item.
Having had both I always thought that a decatted 500 sounded to be doing twice the rpm of a pre-cat... nice, but not as nice as the original item.
RIP_puffsorted2 said:
most people seem more than happy (including me) with Offords (near Cambridge) Cherry Bomb conversion (that actually doesn't contain cherry bombs but thats another story ) as once bedded in it gives lots of pops and bangs on the overrun once you know how to provoke it.
Interesting, as when I went to them for advice they recommended having all the cats out, at £500 + VAT, as opposed to de-baffling which only made them £80...) as once bedded in it gives lots of pops and bangs on the overrun once you know how to provoke it.Edited by Simpo Two on Wednesday 17th September 19:46
The age old discussion as to which is best in the pre-cat v's 500 debate will never end.The only real answer is to test drive both,as all models have different plus an minus points.One thing that still quite a few people do not realise is that 500's up to August '95 do not need to pass a cat test,and should be tested as a pre-cat,so if cats really bother you then it might be worth considering as you can remove all of the cats without any issues.
I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
Edited by The AJP Griff on Wednesday 17th September 20:44
Thanks for the replys 
So just to confirm the pre cats (cars not the cats themselves) are all the 4.0 the 4.3 and the 4.5's
and all the 500's come with cats?
You can remove all the cats on the 500's but they wont sound the same as non 500s due to the manifold design? Is it possible in that case to fit a "pre cat" manifold to the 500's and get the same noise (along with removing the main cat obviously)
OR is there some other fundamental difference that is just a characteristic of the 500's that means they will never sound the same as the 4.0/4.3/4.5's
The Griffith will be a step down in performance from my current summer weekend car so above all it has deliver on fun factor of which the sound will play a huge part hopefully! hence the questions
So just to confirm the pre cats (cars not the cats themselves) are all the 4.0 the 4.3 and the 4.5'sand all the 500's come with cats?
You can remove all the cats on the 500's but they wont sound the same as non 500s due to the manifold design? Is it possible in that case to fit a "pre cat" manifold to the 500's and get the same noise (along with removing the main cat obviously)
OR is there some other fundamental difference that is just a characteristic of the 500's that means they will never sound the same as the 4.0/4.3/4.5's
The Griffith will be a step down in performance from my current summer weekend car so above all it has deliver on fun factor of which the sound will play a huge part hopefully! hence the questions
The AJP Griff said:
The age old discussion as to which is best in the pre-cat v's 500 debate will never end.The only real answer is to test drive both,as all models have different plus an minus points.One thing that still quite a few people do not ralise is that 500's up to August '95 do not need to pass a cat test,and should be tested as a pre-cat,so if cats really bother you then it might be worth considering as you can remove all of the cats without any issues.
I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
This is exactly what I was fully intending to do......get a 500 rip ALL the cats out and either refit main cat for MOT.I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
However, reading up on here about the whole pre-cat debate I was worried that the 500 would just never sound the same!
With regards to your last point the cats dont bother me at all...........I can remove them, work around them etc its the sound that I am worried about and was hoping that it was just a matter of changing the exhaust/manifold setup but if its something else then I will have to re think things.................
rsnissan said:
The AJP Griff said:
The age old discussion as to which is best in the pre-cat v's 500 debate will never end.The only real answer is to test drive both,as all models have different plus an minus points.One thing that still quite a few people do not ralise is that 500's up to August '95 do not need to pass a cat test,and should be tested as a pre-cat,so if cats really bother you then it might be worth considering as you can remove all of the cats without any issues.
I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
This is exactly what I was fully intending to do......get a 500 rip ALL the cats out and either refit main cat for MOT.I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
However, reading up on here about the whole pre-cat debate I was worried that the 500 would just never sound the same!
With regards to your last point the cats dont bother me at all...........I can remove them, work around them etc its the sound that I am worried about and was hoping that it was just a matter of changing the exhaust/manifold setup but if its something else then I will have to re think things.................
.I have to say that having had a 500 or two i still hanker after a pre-cat,theres just something about them,not just the sound either.It's a funny thing,-to me the 500 is by far the better car,but now i've had one,i still want for a pre-cat.rsnissan said:
The AJP Griff said:
The age old discussion as to which is best in the pre-cat v's 500 debate will never end.The only real answer is to test drive both,as all models have different plus an minus points.One thing that still quite a few people do not ralise is that 500's up to August '95 do not need to pass a cat test,and should be tested as a pre-cat,so if cats really bother you then it might be worth considering as you can remove all of the cats without any issues.
I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
This is exactly what I was fully intending to do......get a 500 rip ALL the cats out and either refit main cat for MOT.I honestly think that the actual cat bit is one of the last things to think about when buying a Griff.
However, reading up on here about the whole pre-cat debate I was worried that the 500 would just never sound the same!
With regards to your last point the cats dont bother me at all...........I can remove them, work around them etc its the sound that I am worried about and was hoping that it was just a matter of changing the exhaust/manifold setup but if its something else then I will have to re think things.................
to ascertain which you like bestMy 97 500, with cats, without centre silencer...........
http://s60.photobucket.com/albums/h32/pwd95/Video/...
Before the front end respray
http://s60.photobucket.com/albums/h32/pwd95/Video/...
Please view the other vids on there.
http://s60.photobucket.com/albums/h32/pwd95/Video/...
Before the front end respray
http://s60.photobucket.com/albums/h32/pwd95/Video/...
Please view the other vids on there.
Edited by pwd95 on Wednesday 17th September 22:22
Make sure you find out about the state of tune of any TVR engine that you are listening to. The pre-cat cars had a more ‘revvy’ nature. But many of us have tuned engines that are lightened, balanced and have a far more ‘revvy’ nature like the pre-cat cars.
This can make a big difference to the sound character and volume. Do you have any intention to ever do trackday’s? Even if you don’t, TVR ownership has a way of changing your mind.
Many tracks have sound level limits. Your neighbours may have issues too. I have a no cat’s but a standard exhaust from there back, but it’s still far too noisy for tracks.
Next Monday evening you will find the South East London/NW Kent TVRCC at a pub called
The Manor Farm Barn
New Barn Road
Southfleet
Kent
DA13 9PU.
This can make a big difference to the sound character and volume. Do you have any intention to ever do trackday’s? Even if you don’t, TVR ownership has a way of changing your mind.
Many tracks have sound level limits. Your neighbours may have issues too. I have a no cat’s but a standard exhaust from there back, but it’s still far too noisy for tracks.
Next Monday evening you will find the South East London/NW Kent TVRCC at a pub called
The Manor Farm Barn
New Barn Road
Southfleet
Kent
DA13 9PU.
rsnissan said:
cool I can get along to mid essex........where about are the meets? might be the best idea I think. Thanks for the help.
Mid Essex is on lunchtime on the 2nd Sunday of every month @ The Forresters Golf Club Great Totham (near Maldon)Give the RO Pete a quick email on ro@midessextvr.co.uk and he will be more than happy to introduce you to some Griff owners
PWD95 that sounds excellent!!
Thanks guys I will definately get along to one of the meets (if not both!)
I did hear a few Griffs at LeMans this year where we were camping (wouldnt have know what a 500/4.3 BV was from Adam at the time!) so kind of know what I am after already.
It may be the case that I have exaggerated the whole pre-cat thing in my head so I guess the obvious thing to so is see/hear some inthe flesh as it were.
I always buy my "toy" cars on condition not age or mileage (currently have an 86 3dr cosworth) bur were there any other revisions to the range on the later 500s or was it just dash/ventilation and serp engine/T5.
Thanks guys I will definately get along to one of the meets (if not both!)
I did hear a few Griffs at LeMans this year where we were camping (wouldnt have know what a 500/4.3 BV was from Adam at the time!) so kind of know what I am after already.
It may be the case that I have exaggerated the whole pre-cat thing in my head so I guess the obvious thing to so is see/hear some inthe flesh as it were.
I always buy my "toy" cars on condition not age or mileage (currently have an 86 3dr cosworth) bur were there any other revisions to the range on the later 500s or was it just dash/ventilation and serp engine/T5.
Edited by rsnissan on Thursday 18th September 11:02
Believe it or not the fuelling makes a difference too - at idle at least.
I installed lambda sensors and closed loop fuelling (using a cat map) on my 4.3 and it sounded better at idle - fuller, richer - with the standard non-cat map.
Otherwise, what others have said is true. You can make a 5 litre sound more like a precat by de-catting, but manifold design also plays a subtle part. There's much more to the precat sound that just 'louder'. It's about tone and response to throttle position. Probably something to do with the 5 litres being stroked longer than the precats. Dunno... You won't go wrong with either model though. Just make sure you buy on condition not noise!
I installed lambda sensors and closed loop fuelling (using a cat map) on my 4.3 and it sounded better at idle - fuller, richer - with the standard non-cat map.
Otherwise, what others have said is true. You can make a 5 litre sound more like a precat by de-catting, but manifold design also plays a subtle part. There's much more to the precat sound that just 'louder'. It's about tone and response to throttle position. Probably something to do with the 5 litres being stroked longer than the precats. Dunno... You won't go wrong with either model though. Just make sure you buy on condition not noise!
rsnissan said:
...The Griffith will be a step down in performance from my current summer weekend car so above all it has deliver on fun factor of which the sound will play a huge part hopefully! hence the questions
What on earth have you done to your Cossie then, as a Griff500 would nail one no trouble normally? Gassing Station | Griffith | Top of Page | What's New | My Stuff