Exhaust replacement... Devastated

[baviaannl]

Hoping for some advice here really as I've found myself in a pretty bad situation.

 

I've had exhaust issues for a couple of years with one silencer, basically it fell off twice so I had to get it welded back on, each repair later about a year.  Got to a stage a month back where it fell off for a 3rd time so I decided to take it into an exhaust specialist to have the system looked at.

 

They examined the system and told me I needed a new Y pipe with 2 boxes along with 2 front link pipes, he showed me the corrosion to the pipes and to be fair it did look rough.  He quoted me £660 all in all I booked it in.  I did stress that I wanted everything as close to stock as possible and he reassured me that things would be good.

 

Picked it up after the work was done and drove home and I found it awful.  I've lost power and it makes the most awful droning noise, it makes me hate driving the car!

 

I contacted the firm with my observations although was told that by replacing exhaust sections, it would give a different experience and naturally adding stainless steel components world be noisier!

 

I'm at a loss here, just don't know what to do as I've ended up with something I wouldn't have bought after a test drive.  Are there any solutions available for aftermarket systems that can improve things?  Poxy Covid has messed up my finances so don't have much to play with...  Would appreciate any opinions.

[JDM-Fiend]

7 minutes ago, baviaannl said:

Hoping for some advice here really as I've found myself in a pretty bad situation.

 

I've had exhaust issues for a couple of years with one silencer, basically it fell off twice so I had to get it welded back on, each repair later about a year.  Got to a stage a month back where it fell off for a 3rd time so I decided to take it into an exhaust specialist to have the system looked at.

 

They examined the system and told me I needed a new Y pipe with 2 boxes along with 2 front link pipes, he showed me the corrosion to the pipes and to be fair it did look rough.  He quoted me £660 all in all I booked it in.  I did stress that I wanted everything as close to stock as possible and he reassured me that things would be good.

 

Picked it up after the work was done and drove home and I found it awful.  I've lost power and it makes the most awful droning noise, it makes me hate driving the car!

 

I contacted the firm with my observations although was told that by replacing exhaust sections, it would give a different experience and naturally adding stainless steel components world be noisier!

 

I'm at a loss here, just don't know what to do as I've ended up with something I wouldn't have bought after a test drive.  Are there any solutions available for aftermarket systems that can improve things?  Poxy Covid has messed up my finances so don't have much to play with...  Would appreciate any opinions.

Sorry to hear this, that sucks.

 

Maybe look on eBay for a used exhaust, but ultimately you'll risk the same problem and it'll still cost you. Did you pay for it on a credit card? You may have some consumer rights just based on that.

[Linas.P]

Yes sadly that is in line of what you can expect - in IS250 SS exhaust will cause droning on motorway. So really the only option is to either have it made in Aluminised steel (like OE) or go all out with bangs and whistles and have aggressively sounding SS system. If you want quiet car sadly mild steel is the only way.

Now in your position it is kind of too late... unless you wanted to replace all system again.

To begin with I would argue exhaust specialist should do remedial work for free - if you asked them for system "like stock" they should have told you to go mild steel and not SS. Secondly, if you feel car is down on power then they messed something up - it should not be down on power if they kept dimensions and layout. Have they used bigger diameter pipes (bigger pipes would result in lower low end torque)?

Finally, the only advise I could give - they can try to play around with different or more resonators. I assume they kept everything like stock layout (big resonator before the Y). If so maybe adding small high-flow resonators on the straight mid section could reduce the noise and add little bit of the lost back-pressure back. Either way I would insist they do this for free and the only thing they can expect you to pay for are the actual parts e.g. 2x resonators (like £80). The work cost is on them as they certainly mislead you here.

[rich1068]

I'm afraid I have to disagree with some of what you say Linas. When I first bought my GS it has a SS cat back on that did drone. Alright around town if a little un-Lexuslike but noisy and tiresome on any sort of run. The issue was the very small resonator in the middle and small silencers at the rear. I had the entire thing replaced at Tony Banks in Leeds in stainless steel and Lexus serenity was restored. I'd specified a system as close to stock as possible and that's exactly what I got.

I'd argue the OP's fitters weren't really listening to what he wanted or capable of delivering. From what I could gather from Tony it's finding the right balance between performance and sound. Too quiet (larger resonator and silencers) = less power, so I'm not sure how they've made it louder and lose power.

[Linas.P]

What GS we are talking about here? mk2 GS300? Straight-six 2JZ? That will sound glorious with almost any system, including cheap straight pipe. Or is it mk3 GS300 with v6 3GR? Not sure how it sounds, but again it seems that comparison is not like for like. Specifically on IS250 many owners have regretted fitting SS, because SS as material just naturally drones more. This is certainly not the first time this being discussed.

Next issue which is often overlooked is that SS pipes tends to have larger ID and thinner walls for same OD pipe. Below just illustration only, but I guess you get what I am trying to say - it is clear which one will drone more:

Besides most exhaust places seems to work on assumption that "larger is better" and mostly stock 2in+ pipes... Sure that is good for 1000hp Turbo Supra, but massive overkill for NA IS250... if it adds anything then it is just heaps of drone.

I absolutely agree with you that exhaust "specialists" completely ignored what OP asked for, hence I suggested they should remedial work for free. If they would have listened MS would have been better choice. I am not expert, but it seems it is much harder to do quiet SS system - probably possible, but you need somebody to know what they doing (clearly not these guys).

I assume they kept original layout and fitted large resonator before Y. Yet even that won't be enough - as most drone in interior will be coming from long straight pipes in mid section, hence suggestion to fit additional resonators to remove drone exactly there. I must admit this is little bit stabbing in the dark (as most aftermarket exhaust sound tuning), but the only other alternative is to rip everything out and replace it. 

As well it doesn't really matter what rear silencers looks like, silencers literally just does that - silences the exhaust (well unless they are something like "cherry bombs" specifically designed to amplify the sound). Silencers are quite simple - the bigger and more restrictive will be quieter, the smaller and less restrictive will be louder. Resonators on the other hands are very complex - they need to create frequency which is exactly opposite to the drone. This is why aftermarket systems are not such a good idea - they do tend to sound louder, but they tends to drone. This is indicative of resonator not being well suited for the system. And what it takes to make resonator "suited" - well that is job of specialised labs and years of development to make sure resonator removes drone at every possible RPM and engine load (literally millions are spent for each OE system to achieve exactly that). Not something you will find in local exhaust shop for sure.

Regarding loss of power - my assumption lack of back-pressure (bigger ID pipes, less restrictive system overall) results in less low end torque. Car probably makes more top end horsepower, but it will have less low end torque. IS250 is already not great with low end torque (below 3500RPM) and this is just made it worse - as result it will feel down on "power". This is again very typical for aftermarket systems (even good ones) - they will always claims whatever "+20HP + 5NM", but what they fails to say this is "top end" and it is at the expense of low end numbers.

[Pcwesthead]

Talk to Trading Standards. They will be honest if you haven’t a hope,  and helpful if you have.  They are usually practical and calm.  And if there is something you can do, they will walk you through the process.  Stand tall.  It won’t be your last or your biggest challenge, and many of us have done the same sort of thing.  

[Linas.P]

I would probably approach the exhaust "specialists" themselves first and give them chance to fix issue. Trading standards would be last resort measure.

[royoftherovers]

Just now, Linas.P said:

I would probably approach the exhaust "specialists" themselves first and give them chance to fix issue. Trading standards would be last resort measure.

Linas, ask him to contact Tony Banks in Leeds and ask for advice and the best way to go about getting it. Tony B will be able to assess what has gone wrong and how it might be corrected at minimal or no cost.

[olumite]

OP, are the new rear silencers chambered or that "free-flow"?

I've found free-flow silencers to quite bad for drone low end torque loss.

When I had a SS exhaust put on my 3GS at Tony Banks, I insisted on chambered silencers. 

The fitters may yet be able to replace the back boxes or even install baffles (sp?) which should improve the drone at 2-2.5k rpm.

[is200 Newbie]

Exactly the same as what i experienced with mine from a company that made a SS system in Ellesmere Port. It was on my last IS250 and it got to the point that i made one myself as at the time they were not available from the likes of ATS etc as the pattern part had not been released by Lexus.

Made it from 3" mild steel pipe using an IS200 centre resonator and two Rover ZR back boxes. Bit of fiddling around with it but got it right with no noise and it looked good as the Rover boxes, the only ones i found that would fit in the underbody recess, had twin pipes per box and it did make a difference to the way the car performed which was a lot better. The IS200 box fitted great, was a bit smaller but with the bigger pipes and the twin boxes the car went really well.

Unfortunately it was written off !

 

[baviaannl]

On 12/25/2020 at 3:19 AM, Linas.P said:

Regarding loss of power - my assumption lack of back-pressure (bigger ID pipes, less restrictive system overall) results in less low end torque. Car probably makes more top end horsepower, but it will have less low end torque. IS250 is already not great with low end torque (below 3500RPM) and this is just made it worse - as result it will feel down on "power". This is again very typical for aftermarket systems (even good ones) - they will always claims whatever "+20HP + 5NM", but what they fails to say this is "top end" and it is at the expense of low end numbers.

Your opinion is right on the money, it's low end related entirely!

 

Got it on the motorway last night and in my opinion at the top end it had more power than with the original exhaust, it just kept going!

 

Low end however is a shambles, thought the acceleration was beautiful on the stock exhaust, smooth and quiet and the cruisong performance was great, quiet and refined, very enjoyable.  Now I have a droning mess!  As I said to my wife last night, if it had of performed like that on the test drive, I'd of walked!

 

I'm going to visit them first thing in the morning and try and catch the manager and see if he's interested in helping with this issue, guy on the reception when I booked told me it would both sound and perform perfectly, it currently does neither!!

[rich1068]

We're down to if they care about customer service or not. Here's to a successful outcome 

[nicnac]

1 hour ago, baviaannl said:

Your opinion is right on the money, it's low end related entirely!

 

Got it on the motorway last night and in my opinion at the top end it had more power than with the original exhaust, it just kept going!

 

Low end however is a shambles, thought the acceleration was beautiful on the stock exhaust, smooth and quiet and the cruisong performance was great, quiet and refined, very enjoyable.  Now I have a droning mess!  As I said to my wife last night, if it had of performed like that on the test drive, I'd of walked!

 

I'm going to visit them first thing in the morning and try and catch the manager and see if he's interested in helping with this issue, guy on the reception when I booked told me it would both sound and perform perfectly, it currently does neither!!

I n my opinion the engineers belonging to a motor manufacturer usually get the balance between a smooth torque curve and high end power and noise about as good as you can get , for a comfortable road car with refinement . After market products may improve one area or another !. ie noise for boy racers or BHP for guys who sit on a dyno machine and check graphs. My advice .........stick to OEM and leave your car the way it was designed . !!!I just put the rear sections and middle sections on an SC . OEM was around 300 per section so not that much more than SS . It will last another 15 years so thats OK with me !!