Exhaust for G60 - backpressure?

[Andy T 0]

My G60 has a cat removed full scorpion system, but with a powrflow back box.

 

Its very loud, so I want to get it altered. I've spoke to my local powerflex agent, they say they can either fit an additional silencer, or change the rear box but keep the tailpipe(I really like the tailpipe)

 

In terms of backpressure, what is good for a G60(with stage 4, chip &pulley) Is a free flowing system best suited, or do you lose a load of bottom end torque? Would a standard VW system be too restrictive considering the mods?

 

I just wondered whether exhaust manufacturers take these things into account, especially powerflow, as their systems are custom built.

 

 

cheers,

[spoier 0]

No modern car "needs" backpressure that is a myth

 

http://www.uucmotorwerks.com/html_produ ... uemyth.htm

 

mo' flow mo' bettah

[trendy tramp 0]

dead right spoier - less backbressure is better. because turbocharged engines by their very nature have a back pressure it was previously thought it was a necessity. absolutely not, on a TC engine minimal backpressure is best.

 

tt

[Jim 2]

Indeed.. when my Corrados backbox rusted off I was forced to drive around for a few days without a backbox at all.... I guess that would be no back pressure, but I found that it felt peppier without the backbox than it did when it had it on.

 

Or maybe it was just the insane noise that it made :D

[16VG60 1]

Backpreasure In a forced induction car exhaust system is deffinately undesirable, and furthermore if present will only serve to counteract boost causing a preasure wall. When i was developing my 16VG60 engine we encountered this situation on the first rolling road session. I was then running a ported and flowed 16V cast manifold, G60 front pipe and G60 Milltek Cat bypass system. The answer was to remove the primary restriction this being the OE G60 front pipe, and to design a larger bore full flow repacement. Secondly, given the engines ability to create substantially more exhaust gasses, to create a system that used the largest bore possible whilst offering the same high standard of fit in particular over the rear tosion beam. Milltek built both of these components and as predicted the second trip to the roollers saw the the required results.

 

The front pipes will fit into any system that previously accepted the OE item and the whole system is good for both 16V and G60 Corrado's. I now sell the front pipe and high flow exhaust systems as an upgrade, and have just commissioned a batch of front pipes to satisfy customer orders to date. If any of you are interested please send me a pm for more details.

[steveo29 0]

16v g60....would this fit a golf?? ....where does it bolt to i.e downpipe/manifold ?

[G60JAY 0]

When i removed my cat i replaced it with a jetex 2.5" straight through silencer and it worked a treat.

[16VG60 1]

Stevo29,

 

the Corrado as i am sure you are aware shares basic chassis characteristics with the Mk2 Golf, and this has allowed me allready to fit this front pipe to one other Golf GTI G60. So Yes it will fit. The font pipe bolts to the OE manifold and utilises the six stud mounting, it then connects at the other end to the system using the OE three bolt flange. I would recomend that in order to get the best out of this mod you have your cast exhaust manifold ported and flowed. This is a service i can offer.

[forcefed 0]

arr these sound great ... how much do the standerd down pipes with no cat restrict the g60 engine and what performance gain do i get from a set of these downpipes. are they made of st/st ? will they mate up with my powerflow system ok ? oh and how much are they and what is delivery time on them ..... sorry for all the questions just i have a leaking downpipe and this could be the answer to my problem as well as mabee an extra bhp or 2 ??

thanks Q

[16VG60 1]

The standard downpipes cause a significant restriction to exhaust flow they were costing my 16VG60 about 15 bhp as far as could be established by rolling road evaluation. Performance gains from exhaust mods are purely relative to engine state and tuning but you will notice a difference given that you are running with a good quality system. These front pipes will marry up with your system as long as your setup retains the three bolt flange that does/did connect to the cat. Cost of these custom built high flow pipes is £250 plus p&p. I am taking orders now that will be built ready for delivery in the first week of November.

 

I hope this answers your questions, if i have left anything out please get in touch with me.

[Andy T 0]

Cheers, exactly what I wanted to know.

 

I will have a proper look under the car to see what i've got, cos i'm sure I could still see the CAT (or it least its sheilding)

 

So really I should aim for a reduction in noise but without any decrease in flow?

 

Is it possible to havea quiet exhaust that is almost free flowing?

 

cheers,

[16VG60 1]

With this system, Yes.