Bloody Noise levels!!!

General General Lotus Talk
1

Had a great day at Donnington on Sunday. Did every session and the car ran faultlessly again!!!

However I was clocked at a drive by noise level of 101db.

I use the new elise parts exhaust including there manifold and silenced de-cat pipe.

I did speak to the guys at Elise parts after the problems I had at Bedford a week or two ago and they are makeing me a new larger silenced decat pipe

I certainly hope it does the trick!!!

What exhauts does everybody else run and do you also get noise problems???

Sean…

2

I run the Janspeed Supersports with the Eliseparts Silenced CRP, but this is the original SCRP not the new one.

I can pass at Bedford easily, Goodwood etc. Since fitting the SCRP I have never had an issue.

This is the one I have.
[image]http://www.eliseparts.com/images/exhaust/silence-cat-replace.jpg[/image]

3

I have the same SCRP as Mark A but with a Powerspeed rear box.
The Powerspeed is repackable but I havent had to yet in 10K miles of mostly track use, it is a relative large box but I have never had a problem with noise - its deep and not “tinny” which I like

4

Cheers guys. Yeah the Elise parts SCRP tthat I have currently is a round 4" silencer, I wonder why they changed from the original design that you have?

I will see how I get on with the new SCRP that they are going to send me. But if I still have problems then the rear silencer will have to be changed.

What exhaust manifolds do you guys use??? Mind you I guess the diferance the manifold would make to the noise level would be minimal?

Sean…

5

My car still has the std manifold.

I was surprised when I saw one of the new Eliseparts SCRP on someones car at Goodwood in November, when I say on the car, it was actually being replaced by a Cat as he had failed the noise test.

6

Sean B - a 4" scrp doesn’t leave much volume for silencing if you’re using the correct dia perf tube (2.5"o/d ). I know some bring down that dia some to 2.25". Certainly Mark-A’s oval has a larger volume but it’s not re-packable.Come to think of it,I’ve never seen a re-packable scrp! IMO a sports cat is best - a good silencer, no loss in power and no re-packing issues.

One thing is puzzling me tho, how come most (some?) of the Caterhams pass the noise tests with comparable size silencers + bore and in some cases with more power?

7

The Moto-build SCRP has no packing and with my Larini exhaust I got 93.5dB when I tested it after it was fitted - see here and here for pics.

Although it is fair to say at least one other thinks it is uneffective.

Ian