Gone TTC and now exhaust booms at low revs - how to remedy?

Does someone on here understand the logic behind exhaust note related to diameters of pipes, exit pipes and expansion chambers etc?!

Basically in sequential my custom exhaust was ace, sounded nice and burbly in low revs and screamed in high revs. Now I have gone TTC it obviously sounds the same at high revs, but now at low revs (below 4K) and especially when cruising at 70-80 in 6th the whole car now "booms". Plus It doesn't sound like a 6 pot anymore at low revs, more like an evo or something.

It has full de-cat, and a 2 1/2 inch pipe running all the way to the back. Then a custom silencer and a 5" exit (too big now, but four years ago I thought it was cool!!!)

Is there an easy way to get my burble back - please help!

(I have mates in the welding and fabricating industry, so chopping and welding is no problem at all)

TTC does make it sound like that (like crap). Put it back to sequential would be my advice.

Why have changed it to TTC anyway?

Like Jake says the easiest and most sensible approach is to go back to sequential, the noise you have now is normal for TTC, can't see the appeal myself.

Fitted hybrids and EManage Ultimate. The car runs a lot better in TTC with my current set-up, but the exhaust note pi$$es me off. Surely there is an easy way to sort out the boom? Plus it has been mapped for that so can't just swap the pipes over and go back to Seq that easily!

electronic cut-out valve maybe

Fitted hybrids and EManage Ultimate. The car runs a lot better in TTC with my current set-up, but the exhaust note pi$$es me off. Surely there is an easy way to sort out the boom? Plus it has been mapped for that so can't just swap the pipes over and go back to Seq that easily!

Different exhaust?

electronic cut-out valve maybe

I did think about this - have a switch to actuate the exhaust valve if I wanted a "quiet" note. Would have to remember to open it for spirited moments though. I'm sure I have read on here pople having done this sort of mod.

Of course would be better to just sort the exhuast note out once and for all. Anyone gone TTC and got a nice note? What exhaust have you got if so?

In normal sequential mode only half the exhaust is functioning. In TTC it keeps open an exhaust valve throughout the rev range which usually only opens at 4000rpm

In normal sequential mode only half the exhaust is functioning. In TTC it keeps open an exhaust valve throughout the rev range which usually only opens at 4000rpm

I understand that cheers bud. Fitted the Hybrids myself so have had it all in my hands, including pneumatic diagrams

My exhaust is the XS power one and sounded OK in TTC, however it is quite loud in TTC and single, my solution was the fit an Apexi exhaust valve, i believe you can now get the electronic controller again (ask nic) so it would be fully programmable to open at certain rpm;)

I had the same problem. On TTC and the Greddy Nur Spec the booming drove me nuts!

I replaced the Nur Spec with a 3" Greddy and the problem was solved. Back to the nice low rumble and scream at high rpm's.

The TTC conversion doesn't sound like @#$ you have to tune the sound because you now have a "single setup". I am loving the TTC setup, but then again... I love my auto

Just 2cts from The Netherlands

I thought as much - I have driven it more now and it jsut sounds like a GTR now, but the boom is too much. So what is the difference between a nur spec and a 3"? Physically I mean?