Exhaust Goes Bad! Need Advice

[resh]

Alright so the story goes I want my r34 to sound a little meaner and opt to get a catback exhaust put in.

I go to settlement rd exhaust center (I'm in the northern suburbs and these guys quoted a good price), asked for a 2.25" mild steel system with stainless steel tips and didnt not want any drone. Since they didn't have stainless steel tips one of the guys advised i go to supercheap/autobarn and buy some as they wont affect the sound of the exhaust. Anyway they do the system, it drones like all hell, so they suggest changing the muffler and clamp it on so i can hear it before any welding (keep in mind i had to pay more for this extra muffler).It sounds sweet, almost no drone so i'm happy but they told me to come back to get the tips welded on and such (in the meantime there is a steel pipe coming out of the muffler).

I go back the next day, they weld the tips on, I pay the extra amount, drive off and guess what... drone is back and just as bad. So i ring them up and explain, asking if they can fix it/how and they basically tell me to get stuffed and that if i dont pay more they arent fixing anything. Just want to know if you guys think I should be allowed to have it fixed for free considering they didnt say anything about the tips/told me it was fine to use ones from other places. I'm sending a letter in writing to them tomrorow before going to consumer affairs but was just wondering if anyone else has had simmilar experiences/suggestions for me as right now i feel like I've got half a leg to stand on and am unsure if i should even bother.

Thanks guys and sorry if i wasnt supposed to mention the name of the business... I just didnt think what I've said amounts to slander?

[rs73]

R34 25GT, hey? N/A?

N/A tends to drone more, unfortunately. It's a whole lot different to turbo car exhaust that usually goes quieter as soon as the turbo went on boost, before building up noise towards high rpm.

Does the system has a centre resonator? Adding 1 or 2 resonators before the final exhaust may help. But it's a tricky engineering, as with N/A the correct amount of back pressure is required for the exhaust to be able to flow exhaust gas effectively as there's no forced induction assistance to push the exhaust gas out of the tip as quick as possible, so only the alternating cylinder action that keeps everything in motion... get this wrong you'll loose power, and heaps of other issues. Nissan engineers spent countless hours putting their research into your factory exhaust, I doubt any exhaust shop will be able to come up with a perfect custom/one off solution overnight (unless they've done the same design on the same RB25DE engine before).

Sometimes it is better to spend a bit more and get a JDM catback that bolts on and have gone through extensive research from the manufacturers (e.g. HKS, Trust, Apexi) rather than cutting corners and end up going back and forth for different adjustment until you get perfectly what you want.

Unless the exhaust workshop has done a similar custom design on exactly another R34 GT N/A and their custom system has been proved to be good.

Anything else, be prepared for multiple trips and minor adjustments as I said, until you get that perfect sound and performance gain.

[jakez88]

sounds like what your doing so far is right...they should fix it if it doesn't sound right as u did inform them that u didn't want it to drone.

send em the letter and see what happens after that.

thats why i never do custom exhausts unless i truly believe in the quality of the workshop's products.

Jap systems all the way!! i reckon a used one may have sounded better and also saved you abit of cash...but in the mean time just try and fix those guys up.

[resh]

Yeah its got an 18inch resonator in it, i knew with an n/a that i'd have SOME drone but you should hear it, it makes things in my car shake! The only reason i've gone with a custom job was because Jap exhausts for n/a r34's are damn near impossible to come by, and then they are almost always cannons which i wanted to steer clear of.

I'd be more than happy to go back and fourth to get things fixed up but if i'm paying more everytime it doesnt seem right as i'm paying for their mistakes essentially. The weird thing is it was fine when it had a temporary pipe coming out acting as the exhaust tip, quiet as anything in the cabin, the smallest almost inaudible drone b/w 2k and 2.4k rpm but once those tips went on it all went sour again.

[rs73]

How is it mounted, is there a rubber grommet (spelling?) on the mount? That should absorb some vibration.

Also is the temp pipe you had before the same size with the exhaust tip you got now? Bigger exhaust tip will affect the noise too.

If anyone tell you a 60mm exhaust tip and a 115mm exhaust tip doesn't make a difference in noise, I would never believe them.

I had an Apexi silencer cone, which silenced my 115mm exhaust tip of the old R33 gtst, the cone shape only have maybe 2" opening.

[resh]

When it comes to all of this I'm not down with most of the lingo. The only rubber things are those oval shaped holes which the exhaust's fixtures are placed into (hope that makes sense). I noticed the stock exhaust had a big round rubber thing hanging off it? Perhaps this is what you are talking about? If so there isn't anything like that on the new one. And that temp pipe is not the same size as the tips on there now. The temp pipe was 2.25" where as the tips on there now are a lot larger than that, and it goes from one inlet to two tips (so i could retain that stock look). Each tip would be roughly 2" in diameter each.

[rs73]

Yes, that mounting rubber is what I mean...

Well 2" round tips x 2 are equal to a surface area of (2"/2)^2 x pi (3.14) x 2 = 6.28 sq-inch

While your temporary pipe was 2.25" with surface area of (2.25"/2)^2 x 3.14 = 3.97 sq-inch

So basically you've increased the exhaust tip opening by 58%, I wouldn't be surprised if your exhaust gets louder.

[resh]

Thanks for all your help rs73.... I should have come to you before going to them haha.

Letter of demand is in the mail, they should receive it tomorrow.

I almost want to go back there and talk to the bloke face to face, but he was such a rude pr*#k to me on the phone I'd probably just be wasting my time.

I'll write up a post if this ever gets fixed to let everyone know.

Thanks again guys!

[resh]

Consumer affairs here I come!

The guy got my letter, told me not to ever come back and go somewhere else !

I also went to another exhaust place, the guy there said the job probably wasn't roadworthy either !!

Ah the joys of a custom exhaust...

Anyway I've noticed this thing bolted onto the flange of the CAT. Is that supposed to be in that location?

If someone would be a dear and check for me under their 34 if its bolted to the outside of the cat it would be greatly appreciated

Pic of what I'm talking about is attached..

[Ronin 09]

that looks fine to me - the welding is a bit like eagle shit but it'll do the job fine

[GTR_STEALTH]

What did u write in the letter?

[CrispyFries]

looks like an earthing strap, needs to go somewhere on the exhaust might as well be the cat

[UNR33L]

not all n/a's sound bad, heres my old 4 door n/a having a bit of a rev :

http://au.youtube.com/watch?v=uRDVFAh0F24&...feature=channel

[(OO)SKYLINE(OO)]

Consumer affairs here I come!

The guy got my letter, told me not to ever come back and go somewhere else !

I also went to another exhaust place, the guy there said the job probably wasn't roadworthy either !!

Ah the joys of a custom exhaust...

Anyway I've noticed this thing bolted onto the flange of the CAT. Is that supposed to be in that location?

If someone would be a dear and check for me under their 34 if its bolted to the outside of the cat it would be greatly appreciated

Pic of what I'm talking about is attached..

By looking at the photo it looks like the earth wiring as what Crispy Fries has said. Its normal and it comes with the car and aslong as it bolted somewhere around that area should be fine.

Welding looks OK, but wouldn't say its the best job ever...

Are you thinking of taking it to the other exhaust place to fix it up?

[resh]

Ah yes an earthing strap... that makes sense. Thanks for the help on that one.

The funny thing is that the welding in that area is by far the best they've done on the exhaust... I probably shouldn't show you guys the rest of the exhaust or some of you may collapse from disbelief.

My letter was very simple, it simply stated what occured in chronological order, then what I would like done to to resolve the issue.

I have done some legal subjects at university so I know exactly how to word those letters so it's not like I deserved the reaction I got.

I am thinking of taking it to the other exhaust place to get it fixed up.. unless someone here has an exhaust place I should be going to?

[(OO)SKYLINE(OO)]

Ah yes an earthing strap... that makes sense. Thanks for the help on that one.

The funny thing is that the welding in that area is by far the best they've done on the exhaust... I probably shouldn't show you guys the rest of the exhaust or some of you may collapse from disbelief.

My letter was very simple, it simply stated what occured in chronological order, then what I would like done to to resolve the issue.

I have done some legal subjects at university so I know exactly how to word those letters so it's not like I deserved the reaction I got.

I am thinking of taking it to the other exhaust place to get it fixed up.. unless someone here has an exhaust place I should be going to?

Where abouts are you, Heidelberg... North East of Melbourne, Victoria... You can take it to Le Mans Automotive in Templestowe.

See Shane as I take my car there and get all the work done.

He can probley make you up an exhaust or he can suggest an exhaust system and get it in for you or fix up your the one you got on now...

[resh]

Ah yes I've heard of Le Mans.. I had no idea they did exhaust work there.

I'll head down there and see what they can do about my current exhaust once my ankle heals up (did it playing hockey... this clearly hasn't been the best week for me).

and again thanks for all the help.