Exhaust noise reduction

Exhaust noise reduction

Author
Discussion

boriszblade

Original Poster:

21 posts

37 months

Thursday 3rd August 2023
quotequote all
I would like to share a very good solution for people who want to reduce the exhaust noise on their Chimaera/Griffith. Most of the people want to make it louder but sometimes the reverse is required, eg. European MOT requirements, sensitive neighbours, or sensitive ears, etc. I got into this issue because my MOT office is very picky and they make sure that the noise is not exceeding 85 db (it measured approx. 100 db on my Chim with all cats in place). Also I started to notice some earache after driving for a long time.
So, I followed an advice one of the forum users suggested a long time ago - Drag Specialities 2.5" baffles. The slide right in the end pipes pretty snugly. I have not drilled the pipes to fit the screw, just pushed them a little harder and they seem to stick inside pretty good.
The result- the noise level at MOT is measured just below 85 db - a significant reduction of approx 15-20 db! Subjectively, there is enough noise to make everyone aware about the TVR presence, but it became more comfortable for me as a driver. Lets say, it became more civilised but definitely not subtle. No other effects on operation of the car noted. No loss of power noted as well, but I have a 500 version, so it is easy not to notice any. smile
I liked the result and I decided to keep them in for daily driving when you don't use the top end of the revs. I will remove them at the track so that the engine breathes better at top revs.
The only draw back I see is the aesthetics, you will see at the pictures. But, I will try to pain them black, that should improve the looks.
Considering the cost - 40+ euro for a pair, I think that this option is a very good one to have for long trips for example, or many other uses.


boriszblade

Original Poster:

21 posts

37 months

Saturday 5th August 2023
quotequote all
Just a quick follow up on my original post. It was a stupid idea not to fix the baffles with the screw. One is lost on the road somewhere as a result. It is good that they are cheap smile

GTRene

17,776 posts

231 months

Saturday 5th August 2023
quotequote all
lol, yeah you have to really fix them good, otherwise a lot pressure at higher revs and the small vibrations can blow them out.

but thats a great noise reduction you got.

LLantrisant

1,002 posts

166 months

Sunday 6th August 2023
quotequote all
apart from the fact that this item may work proplerly in tems of noise reduction, the fixing is so weak that a lost item can harm other motorists.
i would call this dangerous.

boriszblade

Original Poster:

21 posts

37 months

Sunday 6th August 2023
quotequote all
I wanted to avoid drilling a hole in the pipe, but looks it is the only way to fix it reliably. Otherwise it is a bit reckless, agree

clive f

7,250 posts

240 months

Wednesday 9th August 2023
quotequote all
What is the diameter of the hole in the middle of the baffle? the whole thing looks quite small.

sixor8

6,603 posts

275 months

Wednesday 9th August 2023
quotequote all
It says 2.5" on the box in the photo, so I presume that would fit straight on a standard exhaust tip.

boriszblade

Original Poster:

21 posts

37 months

Wednesday 9th August 2023
quotequote all
Exactly, slides right in pretty snugly.

boriszblade

Original Poster:

21 posts

37 months

Wednesday 9th August 2023
quotequote all
clive f said:
What is the diameter of the hole in the middle of the baffle? the whole thing looks quite small.
I will measure a bit later and post, but yes, the reduction un the flow is significant.

indigochim

1,661 posts

137 months

Wednesday 9th August 2023
quotequote all
That looks ideal for long trips where the drone can become annoying I bought something similar off aliexpress that was sold for motorbike exhausts. I've not tried them as I was unsure if they'd have a negative effect on the car.

What negative impact could using them have I'm thinking for just occasional use for long motorway runs if I was just sat at 70 for a few hours.

indigochim

1,661 posts

137 months

Wednesday 9th August 2023
quotequote all
This is similar to what I got the grub screws are reversable to clamp inside the exhaust.


boriszblade

Original Poster:

21 posts

37 months

Wednesday 9th August 2023
quotequote all
These cheap baffles were the first which I bought. Total waste of money IMHO, their effect is hardly noticeable, max 5dB reduction.

indigochim

1,661 posts

137 months

Thursday 10th August 2023
quotequote all
Good to know, thanks they can stay in the cupboard.

boriszblade

Original Poster:

21 posts

37 months

Saturday 12th August 2023
quotequote all
clive f said:
What is the diameter of the hole in the middle of the baffle? the whole thing looks quite small.
Just measured it - 3 cm. That is exactly twice as less as the original 6 cm.