Exhaust setups

[HaydEn]

So, I've been thinking about getting an exhaust system. However, from what i have read is, the corrado is rated at a few kW more due to a 2.36" exhaust and different cat, compared to the golf's 2.25".

So theoretically, if I ran a 2.36" with a different cat i should see an increase in power, noise and still remain a healthy amount of back pressure. Or alternatively can I run a bit bigger, such as a 2.5, and not lose much down low torque/power and backpressure?

As for tips I have no idea; I've seen the usual types I.e Remus, Magnaflow etc. I was think maybe the Xforce Varex if anyone has used one?

What have some of you other VR6 guys done?

[rayray086]

The Varex works well with all types of cars. Useful if you live in an area littered with defect-happy cops (Newcastle hahaha).

[Ben J]

I just took the suitcase out of mine to make it sound like a beast, but I was going to go for a 2.5 inch system.

Some people think 2.25 makes more then the 2.5 but its been proven that 2.5 makes more power across the whole rev range, and on worked motors a 3 inch makes even more still. I was going to try this one TT Exhaust cat back '95-early'99 Golf Mk3 VR6 Full 2.5 w/Stainless Magnaflow Muffler [253 440TM] - $390.00 : Techtonics Tuning, VW and Audi Performance Tuning and Repair Parts

[The_Hawk]

I have a 2.5" and it does open up the range a little, although I have never had the car with the full stock exhaust so can't really comment on a real "before" That said, I went 2.5" in the lead up to a forced induction setup (which is yet to happen).

You should come down to one of our meets, there is usually a few VR6's around with various setup's for you to see how different things sound

[HaydEn]

Interesting thanks or the replies.

So for a full system, I could expect $390 for that cat back $250-$350 for a cat and approximately $200 for the piping from the headers to the cat?

[Ben J]

Dont forget you have to add shipping from the US to that, and being a big bulky exhaust system thats likely to be a few hundred.

I would go with this cat 42 Draft Designs

And as far as im aware for some reason getting after market headers and downpipe doesnt make any real power difference on the vr6 (except for a couple which are over $1500 each) but if you port out the exhaust manifolds and have the downpipes welded were they meet the flange from the outside, and grind out the weld on the inside and open it up on the inside, you make almost as much power as the one or two good sets of extractors which do make good power.

[HaydEn]

Of course; I hate shipping.

My plan was to get a shop to make up something similar in design.

As for the headers, I was told they were aftermarket, so if anything they would be those $70 fleabay one's.

Those cats are good, considering they have the sensor mount in built compared to other ones I've seen thus far.

I'll hopefully get to an exhaust shop tomorrow and will post up what occurs.

Thanks.

[HaydEn]

So I require some more advice please!!!

I took a visit to a local exhaust shop and he said to check out the the oxygen sensor in the exhaust, as running a 200cell cat could cause it to throw engine warning codes.

So firstly would this be the case?

Could I rectify the issue by getting a chip or piggyback ecu if this were to be the case?

[sleg]

Hey, I'm running a Brospeed branch, high flow cat, 2.5" piping with a magnaflow resonator and back box.
There is a bit of a drone when youre at speed, but I put dynamat in the truck and that has helped a little bit.

[VR28LT]

i thought the 02 sensor was located before the cat on the VR ???

if so i cant see why you would have problems

[HaydEn]

i thought the 02 sensor was located before the cat on the VR ???

if so i cant see why you would have problems

That's what I thought going off the photos of systems I have seen.

However, this guy is not necessarily an expert he just said he's done a few mk4 32's.

But the situation could be rectified if I got the Magnaflow cat with the built in oxygen sensor mount; from this link, and weld it so the sensor is before the cat
42 Draft Designs

Thanks mrVR6exy

[VR28LT]

Yeah i know the later VRs have before and after the cat , but im pretty sure early 12v only have the one .

If i can remember Mickey ran that high flow cat from 42 DD and also Marty ( veedubs ) in his 3dr VR

If i can recall slight mods were needed to actually fit them but this was a while ago so dont take my word for it

[HaydEn]

Slight mod mods in term of making it fit under the car, I.e. Bashing in the floor pan. Or to the exhaust itself?

[schoona]

So, I've been thinking about getting an exhaust system. However, from what i have read is, the corrado is rated at a few kW more due to a 2.36" exhaust and different cat, compared to the golf's 2.25".

So theoretically, if I ran a 2.36" with a different cat i should see an increase in power, noise and still remain a healthy amount of back pressure. Or alternatively can I run a bit bigger, such as a 2.5, and not lose much down low torque/power and backpressure?

As for tips I have no idea; I've seen the usual types I.e Remus, Magnaflow etc. I was think maybe the Xforce Varex if anyone has used one?

What have some of you other VR6 guys done?

Hey dude,

where did you go in Newy?
Backpressure isn't right. You want good exhaust gas velocity and trying to aid scavenging (negative pressures being filled by the next exhausting cylinder so you have smooth flow). Then need to balance the speed becasue the wrong cooling rates affect the car.

There are heaps of threads on VR6 exhausts on here. My advice is buy the Magnaflow cat-back off the shelf system like what Mickey had on his VR. Go the cat as well.

My build thread has a video of what my 2.25" sounded like with a Magnaflow rear box.

My car was definitely peakier with the 2.25, but I haven't driven a 2.5". I made 108 fwkw with an open pod off the MAF lol.

[HaydEn]

I went to premier exhausts at sandgate. Just to get a rough idea on the cost.

Are you saying that 2.5" would lose a fair bit of back pressure?

I've heard your Magnaflow and it does sound very good.