Cosmicalien Posted July 5, 2016 Share Posted July 5, 2016 Hello. My car is booked in for a muffler delete tomorrow on my 2012 Subaru Wrx Sti type UK saloon I'm doing axle back only . I'm a bit concerned about something I read on the forums . One of the posters said that if you install a bigger down pipe it reduces back pressure makes the engine work harder and may cause ringland failure. What you saying fellas. Quote Link to comment Share on other sites More sharing options...
Scoobyghost Posted July 5, 2016 Share Posted July 5, 2016 On a turbo car removing the downpipe helps the engine breathe quicker. Lower back pressure could have it's downsides being that everything can move quick and with more force. It's a fine line between power modification and every day reliability. If you are only having a rear box put on it will have little influence to how the engine runs. Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 Hello thank you for your reply. I believe there will be no silencers just straight pipes from the axle back. Am i safe to do that. Quote Link to comment Share on other sites More sharing options...
MJP02 Posted July 5, 2016 Share Posted July 5, 2016 Seen this done to a 2016 sti last Saturday, it was stupidly loud. was at scooby clinic and their opinion was that due to 0 back pressure this would actually reduce the performance. Quote Link to comment Share on other sites More sharing options...
GeoffLeggy Posted July 5, 2016 Share Posted July 5, 2016 Are you talking about just removing the back boxes in favour for straight pipes? Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 Really. They did suggest adding 2 small silencers just to quiet it down. Will these offer enough back pressure. Hmmm Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 Hello Geoff leggy yes just remove the silencers and replace with straight pipes. I believe similar to the Nameless American muffler delete kit. Quote Link to comment Share on other sites More sharing options...
GeoffLeggy Posted July 5, 2016 Share Posted July 5, 2016 It's only going to come down to noise. If your keeping the rest stock ie cats then no worries about back pressure and even then it's an interesting debate Ok mines not a 2.5 but ran full decats and only a relative small back box for a good time with no issue. I still run decat and only small back box on secondary. Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 Don't really want to spend £450 and end up with reduced power. May leave as is. I think the quad tail pipes are too tucked away they needed to be more level with the rear bumper. Quote Link to comment Share on other sites More sharing options...
GeoffLeggy Posted July 5, 2016 Share Posted July 5, 2016 There's not going to be any power loss. The only thing will be the change in tone/noise. £450 is a lot of money though! I'd expect for that money you'd easily get dual back boxes and choice of tails. Who's quoting? Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 A company called Custom Chrome in Nuneaton. I get the choice of any tips I want and lifetime guarantee. All hand made while i watch. Quote Link to comment Share on other sites More sharing options...
GeoffLeggy Posted July 5, 2016 Share Posted July 5, 2016 If they are just cutting and running straight pipes for that money forget it. I got my Jag back box deletes from rear axle done for £170! If it include some sports boxes then ok but still on upper limit! Quote Link to comment Share on other sites More sharing options...
Scoobyghost Posted July 5, 2016 Share Posted July 5, 2016 We need to clear up what section of exhaust you are getting done. Axle back suggest just the rear section which will make relatively no difference to power and may give you a louder car. Also will have no impact on back pressure. Cat back would suggest a centre section and rear section leaving the standard downpipe and cat in place. That will give you much more noise, small power gain but again little to no difference on back pressure. turbo back is basically the full exhaust system and having no cat in the downpipe will give a large power gain, take away a lot of back pressure and depending on boxes in the centre and rear will make it much noisier. If you are having a full system with no cat in the downpipe it will need to be mapped. For centre and rear box changes mapping is not essential. Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 They did originally quote me £250 but with silencers it's £100 extra per side . Quote Link to comment Share on other sites More sharing options...
GeoffLeggy Posted July 5, 2016 Share Posted July 5, 2016 Upto you mate what you think is value of course but def don't worry about power etc, won't make any difference if your only taking the back section out Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 Scoobyghost hello I'm only getting the sections after the axle replaced. Should look like the images I've added Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 5, 2016 Author Share Posted July 5, 2016 Thank you for your help putting my mind at ease. I'm considering buying the same car 2012 Subaru Wrx Sti saloon it only has 22000 miles on it mine has 58000 this one is in white mine is plasma blue. Can't help but feel paranoid about how it's been looked after 3 Subaru stamps 1 from Vauxhall???? And 1 from the dealer itself JCT600 Price Right in Leeds. Ringland issues and all that bugging me fellas. Quote Link to comment Share on other sites More sharing options...
Scoobyghost Posted July 5, 2016 Share Posted July 5, 2016 In regards to you exhaust work that rear section will be nothing to worry about. 450 sounds a lot though. I'm sure some fabricators do full systems for similar price Quote Link to comment Share on other sites More sharing options...
stants Posted July 6, 2016 Share Posted July 6, 2016 Who the hell are price right ? I live in leeds and haven't heard of them 🤔 Sent from my SM-G930F using Tapatalk Quote Link to comment Share on other sites More sharing options...
Cosmicalien Posted July 6, 2016 Author Share Posted July 6, 2016 Also known as i believe JCT600 my friend. Quote Link to comment Share on other sites More sharing options...
stants Posted July 6, 2016 Share Posted July 6, 2016 Ah okay I thought you said jct and price right [emoji23] Sent from my SM-G930F using Tapatalk Quote Link to comment Share on other sites More sharing options...
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