620R exhaust

[jackg]

Morning

I've just picked up a new 620R which has the exhaust exiting at the back. I'm looking for a decat side exit pipe and can't see it on Caterham's site. Does anyone know where I can get one?

Also, what are the common performance mods for the 620R, it's mainly for track use.
ta

[nigelpugh7]

jackg said:

Morning

I've just picked up a new 620R which has the exhaust exiting at the back. I'm looking for a decat side exit pipe and can't see it on Caterham's site. Does anyone know where I can get one?

Also, what are the common performance mods for the 620R, it's mainly for track use.
ta

It's one of the needed additions to a 620r sadly, as it's the only way to get the noise down low enough to get on most track days.

There's nothing to stop you fitting a side exit exhaust, i had the Raceco titanium exhaust on my last R500, very high quality item.

But I suspect if you did fit one to your 620R you would no longer be under the noise level for pretty much all the race tracks.

Not sure what mods you would need for track use, it's got pretty much everything you would ever need in terms of performance, braking and handling.!

[curley]

As Nigel says , forget about a side exit exhaust on a 620 for track work .

One of the first owners tried one at Silverstone and was shown the exit when he measured 110DB drive by !!

After fitting the rear exhaust on my 620R i decided i would never use the side exit one again and sold it to an R400 owner .The rear unit is so much neater with the cat hidden inside the first silencer

You can buy the side exit version from CC if you really want one . the link below looks similar to the one i had but ring them and they will confirm . You will also need the cat bypass pipe .............................. and some good quality ear defenders .

https://caterhamparts.co.uk/silencers/3694-7q-re-p...

[short-shift]

I'm not sure if a Raceco unit wouldn't be effective neough to meet most track day noise level requirements - thereby saving the awful-looking rear installation of the standard 620R system (actually, it's more the way that the pipework curls under the floor, under the driver, than the apearance from the rear that I object to, but either way it's just not in keeping with the spirit of the car...).

Has anyone got experience of a Raceco on an R620? They are really effective at reducing noise levels; I have a shorter-thn-recommended one (a bespoke length) fitted to my R500D and it is, subjectively, much quieter than the standard Cheesman-supplied exhaust system. I've used it a couple of times on track and had no problems. So, I'm not in a posiion to say that a Raceco would work on a 620R butI'd say it's got a good chance, particularly if it's left at the normal length for a Duratec installation.

Anyone got real experience?

James

[DCL]

There's more than simply exhaust noise to think about. The 620 has the MBE flat shift and the map uses torque recovery that causes a backfire with each shift. That really needs the extra length of the rear exit to keep it acceptable. It doesn't matter how good you exhaust is, if the backfire ignites is after the silencer.

[jackg]

I don't think raceco exist a more?

[short-shift]

Whilst Ammo (who used to be Raceco, and was most well known for special engine builds as well as supplying silencers) packed up the business a year or so ago, Raceco silencers are still very much available through Mike Riley - the very man who, I believe, made them for Ammo all along. They are beautifully engineered and manufactured; highly recommended.

James

[nigelpugh7]

short-shift said:

Whilst Ammo (who used to be Raceco, and was most well known for special engine builds as well as supplying silencers) packed up the business a year or so ago, Raceco silencers are still very much available through Mike Riley - the very man who, I believe, made them for Ammo all along. They are beautifully engineered and manufactured; highly recommended.

James

Yep still available from Mike Riley.

http://www.raceco.com/silencers.html

I still have mine in the garage from my R500.

A quality product and managed to get my R500 down to 98db at Bedford autodrome, although that was with the carbon airbox intake too.

I think there are more issues with fuelling on the 620 to take care of though as well, so not sure just fitting a raceco silencer would work.

I bet it would make some cracking flames from a side exhaust though!

[curley]

Caterham tried ( using the services of Cranfield ) for six months to get an acceptable side exit solution for the 620 .

They gave up .

I am not suggesting its impossible , just highly unlikely , you will find a side exit solution that allows use on most tracks .

[pikeyboy]

I followed a 620r at spa in the summer on the gold track days and it was popping flames out when changing gear. It was black flagged for noise and had the rear exit exhaust system fitted.

[LB14]

boy said:

I followed a 620r at spa in the summer on the gold track days and it was popping flames out when changing gear. It was black flagged for noise and had the rear exit exhaust system fitted.

I've been curious as to why a relatively high number of 620R's seem to go up for sale with little mileage on them and only a year or so old - maybe breaching track noise limits is a factor?

[nigelpugh7]

boy said:

I followed a 620r at spa in the summer on the gold track days and it was popping flames out when changing gear. It was black flagged for noise and had the rear exit exhaust system fitted.

Was it actually spitting flames from the rear exhaust, not seen one with the rear mounted silencer do that before?

Mind you though I think I have only seen about 8 different 620R models on the track/road in total!

[pikeyboy]

LB14 said:

boy said:

I followed a 620r at spa in the summer on the gold track days and it was popping flames out when changing gear. It was black flagged for noise and had the rear exit exhaust system fitted.

I've been curious as to why a relatively high number of 620R's seem to go up for sale with little mileage on them and only a year or so old - maybe breaching track noise limits is a factor?

I cant remember what the drive by noise limit was but IIRC it was 103db so to be black flagged for noise there means you haven't cat in hells chance of getting out at most UK circuits.

[nigelpugh7]

LB14 said:

I've been curious as to why a relatively high number of 620R's seem to go up for sale with little mileage on them and only a year or so old - maybe breaching track noise limits is a factor?

The previous owners I have spoken to all seem to have had problems with noise on track days so I think it could be a factor.

Coupled with the fact that quite a few of the early models had issues, which Caterham spent a fair amount of time and money putting right for those customers.

The ones at the showroom and bookatrack don't seem to be selling that quickly either!

[CycleSi]

..... and I fail to see how (in this high tech world) there isn't an exhaust specialist who cannot design an exhaust to sort out what is obviously a big problem for the 620r.

I got Simpson Exhausts to make my R400 exhaust and there are others who come highly recommended on many forums too. What about the companies who make Formula 1 exhausts - they must know a thing or two about manifold and exhaust design with regard to performance and noise.

Maybe Caterham just aren't talking to the right people?

[DCL]

CycleSi said:

..... and I fail to see how (in this high tech world) there isn't an exhaust specialist who cannot design an exhaust to sort out what is obviously a big problem for the 620r.

I got Simpson Exhausts to make my R400 exhaust and there are others who come highly recommended on many forums too. What about the companies who make Formula 1 exhausts - they must know a thing or two about manifold and exhaust design with regard to performance and noise.

Maybe Caterham just aren't talking to the right people?

I think a lot of what is going on it just poor development - or at least not a holistic approach. There are mapping solutions that Caterham have chosen not to follow, for whatever reason.

[GreigM]

boy said:

I followed a 620r at spa in the summer on the gold track days and it was popping flames out when changing gear. It was black flagged for noise and had the rear exit exhaust system fitted.

That would be me


I have a side exit exhaust that I got a local place to knock up for less than half the caterham price. It comes in about 102db static but I've been black flagged at Spa and Oulton for it. On both occasions I got a substantial amount of running before getting black flagged, so it is the bang on the flat-shift and being unfortunate enough to shift beside their microphone.

As DCL suggests, it is the flat-shift that is the problem, with a different strategy it wouldn't be an issue. On both occasions I had the full rear exit system with me and it takes about 15 mins to change, so not a problem.

Wherever possible I run the side exit as the rear exit system containing the "explosion" is not good for the expensive exhaust - it literally blew my rear section apart (replaced under warranty) and won't be doing the catalyst any good in terms of longevity.

[pikeyboy]

GreigM said:

boy said:

I followed a 620r at spa in the summer on the gold track days and it was popping flames out when changing gear. It was black flagged for noise and had the rear exit exhaust system fitted.

That would be me


I have a side exit exhaust that I got a local place to knock up for less than half the caterham price. It comes in about 102db static but I've been black flagged at Spa and Oulton for it. On both occasions I got a substantial amount of running before getting black flagged, so it is the bang on the flat-shift and being unfortunate enough to shift beside their microphone.

As DCL suggests, it is the flat-shift that is the problem, with a different strategy it wouldn't be an issue. On both occasions I had the full rear exit system with me and it takes about 15 mins to change, so not a problem.

Wherever possible I run the side exit as the rear exit system containing the "explosion" is not good for the expensive exhaust - it literally blew my rear section apart (replaced under warranty) and won't be doing the catalyst any good in terms of longevity.

Its a small world isn't it. My like Pink Fireblade wasn't anywhere near as quick in a straight line as you.

[GreigM]

boy said:

Its a small world isn't it. My like Pink Fireblade wasn't anywhere near as quick in a straight line as you.

I remember you - you were very quick through the bends, driving well. I was having a 'mare at Spa with slicks rubbing on the rear arches and constantly adjusting the suspension. Finally got it mostly sorted by the end of the day and my times suddenly dropped from around 2.58 to 2.50 then the rain came.

[Tazio77]

Raceco - Mike Riley aka Mr Raceco has a new website, it's this one

https://racecoexhausts.co.uk/

Hope this helps.