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GuyT

Getting 410/430 through trackday noise limits

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Having just completed my second track day in the 410 at Goodwood yesterday, I thought it was probably time to report back on the mufflers that Maidstone Sports Cars made for me.

I bought the Exige to use on track so even before collecting it, I was trying to find a good solution to get under noise limits.  I talked at length with Jim from 2bular - he was steering me down his non-valved quiet exhaust.  Nothing became of it and I gave up chasing.  To be honest, I actually like having the standard valved system and have already retro-fitted the exhaust switch on the steering column to fully open the valves as I want.  For just getting from A to B quickly but quietly I love the fact that under 4500rpm you're not going to annoy anyone with the valves closed.

I've used MSC for 20 years now and know them well.  They supported my race Elise and have always found ways to overcome mechanical challenges.  I approached them with my dilemma, saying I wanted to keep my standard exhaust but needed to take at least 3-4db off my static to get onto the majority of circuits.

They went away and put together a solution using a pair of Merlin Motorsport Mild Steel Racing Mufflers joined together and connected to a Y piece that in turn slotted into the current exhaust.  It's held in place using a retaining bolt (having drilled a hole in the bottom of the exhaust).

I tried it initially at Brands Hatch a few weeks ago and tested at 101db at 5,000rpm on static.  I asked the organisers to let me know if I was tripping any drive-by limits and didn't hold back on revs.  At no point did I do so.

Fast forward to yesterday.  I tested at 101db again, this time at 5,250rpm (roughly).  Again, I revved up to 7k around the track - no short shifting and not once did I trigger the sound board.

What you see here is a prototype that I have been testing for them.  It's worked brilliantly for me.  You have to let it cool down to get it out and it takes a few minutes to locate the hole for the fixing screw but otherwise it's no hassle to put on/take off.

For those naysayers that are bound to say it's bad for the engine and increases back pressure, my answer is if it's good enough for some well known race teams and series for use on practice days (running much more expensive engines than mine), it's good enough for me.  It's not like a Supertrapp (which appears to be the equivalent of sticking a banana up your tailpipe) - it's straight through with no baffles but it is enough to just drop the noise enough to get through.  There was certainly no drop in performance yesterday - I was hitting over 150mph before braking for Woodcote which isn't bad for a little ol' Exige.

Some may not like it from an aesthetic point of view, which is fair enough.  You do have to drill a hole in the exhaust which may not be for everyone as well (in case you do get on the floor to check!).  But for me, it's allowed me to get out on track (why I bought the car) and spend the £2k needed to buy another compliant exhaust on harnesses, track days and tyres!

Just to try my luck, I am booked into Bedford as well which has possibly the most strictly enforced noise rules I have ever experienced.

So there you go - I've had a lot of messages after MSC's post appeared up on Facebook and Instagram so thought it was easier to post this up than reply to all!

 

 

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Glad you got where you wanted to noise wise. Can I ask what the cost of this is?

 

Trevor.


I'll get around to it at some point.

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1 hour ago, Trevsked said:

Glad you got where you wanted to noise wise. Can I ask what the cost of this is?

 

Trevor.

On the case - will add once I find out.

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Love the ‘lock , stock and two smokin barrels’ look

I did get a 2bular valveless with xtra silencer, have had it measured at 97 to 102 , at Goodwood again soon so will reading rechecked.

Have to say this’ll be a reasonable fix if they get the pricing pitched right.


Black n gold

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