Posted By: Anonymous
exhaust diameter ??? - 01/02/2016 21:00
hi Guys,
I have a 20VT and am looking to tune it up to around 300-350BHP i have a question about the exhaust though i no i will need to run a 3 inch down pipe off the turbo but will the rest of the exhaust be ok as a 2.25 inch as i already have a sports cat and complete system in 2.25 inch pipe. and wanted to keep it if i could any help or advice would be great! thanks in advance.
Sean.
Posted By: knight7660
Re: exhaust diameter ??? - 01/02/2016 23:35
2.75 inch downpipe will reach that power figure but 2.25 system will strangle it alittle
Posted By: Anonymous
Re: exhaust diameter ??? - 02/02/2016 16:00
Thanks for the input Knight7660 the system I have is completely unrostricted and high flow. Basically the system I have is on a Alfa GTV and I am swapping the engine from the coupe into the GTV and the exhaust system I have on the Alfa cost an absolute mint. It's made by a company called Alfaholics and I wanted to keep as much of it as I can.
http://www.alfaholics.com/browse-parts-b...system-cf3-126/
Posted By: Begbie
Re: exhaust diameter ??? - 02/02/2016 16:17
Why not sell the system on and get a 3" made up? I seem to remember 'Nigel' on here, for a long time, ran with a 3" downpipe and a 2.25" for the rest of the exhaust and whilst it made the power he wanted at the time, it was a restriction as when he went 3" all the way, he freed up quite a lot of BHP and possibly torque.
Ok, lets look at it the other way. What happens if you decide to keep the Alfaholics exhaust system and then decide at a later date you want more power? You've then got the added expense of having to get the downpipe re-fabricated and then a full 3" system, whereas you could have done that in the first place and not spent so much money?
Posted By: Anonymous
Re: exhaust diameter ??? - 02/02/2016 21:33
Why not sell the system on and get a 3" made up? I seem to remember 'Nigel' on here, for a long time, ran with a 3" downpipe and a 2.25" for the rest of the exhaust and whilst it made the power he wanted at the time, it was a restriction as when he went 3" all the way, he freed up quite a lot of BHP and possibly torque.
Ok, lets look at it the other way. What happens if you decide to keep the Alfaholics exhaust system and then decide at a later date you want more power? You've then got the added expense of having to get the downpipe re-fabricated and then a full 3" system, whereas you could have done that in the first place and not spent so much money?
fair point Begbie, looks like i will get rid of the system and just go for a full 3'' system to release its most potential. at least i can have it made with an identical tip so it looks the same at least. thanks.
Posted By: Anonymous
Re: exhaust diameter ??? - 06/02/2016 09:38
Not an expert in any shape or form but is bigger necessarilly better? Exhausts I mean of course!
Not an expert in any shape or form but is bigger necessarilly better? Exhausts I mean of course!
The quicker you can get the exhaust gases out, the quicker you can get the air in, so size and flow does matter with forced induction.
Posted By: Anonymous
Re: exhaust diameter ??? - 09/02/2016 23:31
Just a quick tip
i had a original exhaust on my Audi 3.0v6tdi measured power after remap was 300hp dpf delete + standart exhaust
changed exhaust with 80mm original is 65mm with 2 fre flow muflers
322 hp measured after
so thats on car that goes only to 4500rpm
imagine restriction on engine that goes to 7500rpm
Posted By: pippoinzaghi
Re: exhaust diameter ??? - 10/02/2016 20:55
3" ... are you talking about i.d. or e.d.?