Sportex exhaust!? HELP!

Shobzz09

Junior Member
Aug 31, 2011
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london
Hi guys,
So, I posted a thread before but no reply, but basically, I have a VW polo, Mk4, X reg (2000) and I'm buying a sportex exhaust, do I need a racetube? Or will the backbox do? What difference does a racetube make?
Thanks
 

xtremeleo

3,000 RPM
Senior Member
Oct 18, 2005
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iam sorry nobody replied ur previous post, i dunno about the term u used but iam assuming a backbox is a muffler and racetube is the straight through bullet when replying this sir. i dunno about the diameter of the pipe, but as my thumb of rule, i match a muffler for the torque delivery dat i like and use bullet(s) to help the muffler to muffle the zorst noise
 

xtremeleo

3,000 RPM
Senior Member
Oct 18, 2005
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there are a lot of race tubes in the aftermarket, their function is primarily to deaden the zorst noise imo sir. although ive found tubes dat can alter the zorst flow, but id rather use the rear end muffler for dat
 

Havok_KiD

500 RPM
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Feb 21, 2006
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well likewise hat Xtremelo said... a bullet or what u define as race tube is used to to reduce the sound db of your exhaust and certain bullets are used to give you some good back preasure...

but in some cases... getting a good backbox/muffler will just do the trick with some good route piping to it

So basically all I need is a backbox??
 

Shobzz09

Junior Member
Thread starter
Aug 31, 2011
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501
london
Ok, thats perfect, cheers everyone

---------- Post added at 11:44 PM ---------- 6 hour anti-bump limit - Previous post was at 08:58 PM ----------

Guys, Instead of buying a backbox, will a muffler just do?? What does a muffler actually do?
Thanks
 

xtremeleo

3,000 RPM
Senior Member
Oct 18, 2005
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sure, get the longest muffler dat can be installed behind the bumper, with the proper diameter. then, if needed trim the noise down with race tubes. original aftermarket's zorst like apexi comes with at least 2 race tubes for the skylines. cheers sir
 

upontheriversky

Known Member
Senior Member
Dec 31, 2007
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apart from muffling noise, u will need a racetube that has much bigger diameter than ur collector pipe for best performance. in exhaust pressure wave point of view, it separates ur header and collector length from backbox/tailpipe end so header and collector length is kept tuned.

with racetube separating the 2 parts, ur exhaust system appear "shorter" to the engine for best peak power otherwise with no racetube, the engine will see ur collector pipe to backbox as one long pipe and reduce ur peak power hp