Once i know the correct size, im going to have a custom back box's fitted to my TT, it currently has 2 4.5 inch exits on the back boxes which are too loud, i do however use bungs to silence them which reduce the diamater to 1.5 inches. but with these power is extremely restricted.

 

now what is the smallest diamater i can have on the backbox tail pipes, that is unrestrictive? and will not cause power losses. i may even go for twin doubles exits if this is easier.

 

thanks gents/gals.

 

p.s the car is modded. with larger turbos, and higher boost levels.

an example of the bungs. should it help anyone else in this situation.

 

http://cgi.ebay.co.uk/Exhaust-Bung-Tunable-Insert-To-fit-3-5-4-4-5-5-/400195290487?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item5d2d7f8577

Ive got one of those. When the car hits boost it sounds like its got external wastegates :D

Dont know if its good to restrict the gasses though. ive taken mine off.

if you find what you are looking for i might b interested in buying your old back boxes off you.

do you want a pic damodaman666, mine is a SWB though, so the fitment is different.

if you send me a pic that would be great. hmm that could be a problem but ill speak to my mate who does bodywork about it

bump

 

help still needed on this

bump .

I wouldn't go no less than 2.5" as turbo cars need to get rid of the gasses with the least restriction unlike N/A cars the need back pressure ! I think u should fit better silencers? Or extra ones ? Have u de-cated it?

it has 3 sets silencers, one each side on the japspeed decats, one either side just before the back box, then the two back boxes.

is there anything in them lol that should be pretty quiet !! Mine has decats & rear boxes with nothing in them! Now that's loud !!!