After Market Exhausts
After Market Exhausts
Author
Discussion

Dee Gee

Original Poster:

285 posts

263 months

Saturday 3rd September 2005
quotequote all
How many of you have after market exhaust systems fitted?

If so, has anyone had problems getting through SVA or MOT Tests?

V7TTE

5,625 posts

255 months

Saturday 3rd September 2005
quotequote all
Any particlar era of Vette??

yellowshark454

578 posts

262 months

Sunday 4th September 2005
quotequote all
I have the Borla cat back Stinger system fitted to my C5. No problem with the MOT, only with the noise restrictions at Castle Combe

LuS1fer

43,096 posts

266 months

Sunday 4th September 2005
quotequote all
I have a Z28 Camaro with a Loudmouth replica and no problems at all. As long as you keep the cats at the front, there shouldn't be any difference.

te51cle

2,342 posts

269 months

Sunday 4th September 2005
quotequote all
MoT test should be OK but the SVA test might be a problem if its a new car and the exhaust is very loud. Probably best to get the SVA test done with a standard exhaust then swap to your loud one afterwards.

Interesting report in the current club mag saying that they had an SVA failure because the small switch used to operate the fog lamp was too sharp and had to be rounded off or replaced. The mag also gives some useful phone numbers for workshops who can do SVA preparation.

Dee Gee

Original Poster:

285 posts

263 months

Sunday 4th September 2005
quotequote all
Thanks for the comments.

V7TTE I have on 02 Vert.

I should be OK on the fog light switch. I went for the boring black rocker variety.

>> Edited by Dee Gee on Sunday 4th September 15:13

gtrclive

4,193 posts

304 months

Monday 5th September 2005
quotequote all
SVA Tests now require you have the standard exhaust system fitted, as after market systems invalidate the emmisions...

I know it Boswelox's but that's what the man told me so I have had to remove my Boral System to get though the SVA......

yellowshark454

578 posts

262 months

Monday 5th September 2005
quotequote all
gtrclive said:
SVA Tests now require you have the standard exhaust system fitted, as after market systems invalidate the emmisions...

I know it Boswelox's but that's what the man told me so I have had to remove my Boral System to get though the SVA......


Somewhat strange. The MOT checks emmissions and my C5 complete with Borla exhaust has no problem. How can you invalidate emmisions? You either meet the measurements or you don't, which is what that part of the MOT is all about.

LuS1fer

43,096 posts

266 months

Monday 5th September 2005
quotequote all
It's not emissions, it's noise. Most SVA centres will pass a stock system subject to evidence of compliance and modified systems subject to it only being modified downstream of the cats and using the stock silencer.

HOWEVER, the SVA manual I have says this only applies to Enhanced SVA and a left hand drive vehicle is exempt which suggests it can be as loud as it likes. Most SVA centres do not test emissions if the car complies with the FMVSS or whatever it's called. My Z06 wasn't tested.

Camaro SS

243 posts

267 months

Tuesday 6th September 2005
quotequote all
The pace car has a custom exhaust, no mufflers and high flo cats its quite loud as some will tell you but has no probs with MOT emissions test, also have a Camaro SS with SLP pipes and no cats, also loud but no probs!

franv8

2,212 posts

259 months

Tuesday 6th September 2005
quotequote all
MOT rules on emissions vary with year of manufacture - hence I hav eno need for a cat on my 86. I've got stainless dual exhaust system, cheep aluminised muflers, but with the rest of the system straight through (and of course none of aforementioned cat) it is sufficiently loud! Emissions come out at 1% CO for the MOT, well under the (I think) 3.5% required for this year of vehicle.

As for later cars - for MOT - it's still only a check that your car meets the emissions (CO and Hydrocarbons, HC) limits for the relevant year. And of course leaks and security of the system. Although my mate's maestro failed its mot after the exhaust broke, so we welded what was left of the rusty system back to gether to give a special edition side exit exhaust - hmm....