Exhaust test...

[andy-w]

this weekend at the northeast TVRCC meet i am taking a sound meter.
We shall be comparing the noise levels of the following

Standard chim
My chim = Straight thru
ToonTVR = Offords cherry bomb

And any other car that turns up...then i think we shoud try a rolling road session, swappingthe exhausts between the three cars and see what the difference is...watch this space!!!

[jsr]

Sounds like a bit of fun! Look forward to seeing the results, and maybe hearing them too?!

[andy-w]

jsr said:

Sounds like a bit of fun! Look forward to seeing the results, and maybe hearing them too?!

Ooooooooh...good point...sound clips so people can compare...!!!

I might see if i can get the main cat out before sunday...that should cheer the neighbours up!!!!

[Chauch]

I look forward to the results of this as I have the Cherry Bomb conversion.

When you do the Offords test, can you let us know if pre-cats are in or not?

[andy-w]

i am not sure if john has taken the precats out...but if things go to plan, over the next few weeks we might be swapping exhausts so we can compare results of sound, performance and BHP

[andy-w]

Well for those of you that are interested in having your exhaust changed we did the test today and have the following results.

1st run 2nd run
Standard 110db n/a
Offords 107db 117db
Straight thru 110db 120db

the second run was taken once they had warmed up!!!
Still need to get sound clips and BHP statistics.

Honest opinion.
Offords sounds a bit more 'basey' than and standard but not much louder...straight thru sounds like an american indie 500!!!
But that might be more to do with my chim being an HC???

[toon tvr]

andy-w said:

Well for those of you that are interested in having your exhaust changed we did the test today and have the following results.

1st run 2nd run
Standard 110db n/a
Offords 107db 117db
Straight thru 110db 120db

the second run was taken once they had warmed up!!!
Still need to get sound clips and BHP statistics.

Honest opinion.
Offords sounds a bit more 'basey' than and standard but not much louder...straight thru sounds like an american indie 500!!!
But that might be more to do with my chim being an HC???

Andy mate this post needs editing IMHO take out "a bit" and "but not" replace the latter with "and".
Next time we should measure at a fixed distance ie. 1metre, I'm sure you jumped backwards on the 2nd test when the condensation from the exhaust was sprayed out

[andy-w]

Do you think it was much louder then?
I thought it sounded a lot deeper...which i suppose is louder...???

And i wasnt going to stand there and have a shower from your car...!!!

Yes i think we should definately try it again...fixed distance 1 meter...no higher than 3k revs(?) and we need a rolling road to swap exhausts and measure BHP difference.

Forgot to say...on the way home i reset the meter. and left it on the passenger seat...it peaked at 93db inside car with roof and windows up and no music on!!!

Edited by andy-w on Monday 15th January 12:19

[toon tvr]

Ok so what were you singing then?

[andy-w]

toon tvr said:

Ok so what were you singing then?

hmmm...do i tell the story of the mysterious music comming from inside your car when the stereo was off????

[The Surveyor]

Hi Guys, both the cars sounded great on Sunday, and for a second i almost started to miss mine....

At the last BNG, Bob Smith (tvrbob) did some noise measurements using the official 1m at 45 degrees position which is apparently what they would do for track days. Bob kindly took two readings, one at medium revs (eg track day level), and one giving it a little more... Mine gave readings of 105 dB @ about 3.5k, then a whopping 124 dB max. Not a cultured as the cherry bombs, but bl00dy loud!!!