Would anybody be interested in a 3.5" Turbo back Exhaust

[s2_wot]

Howdy folks,

I'm building a 3.5" (89mm) turbo back exhaust for my s2 coupe.

It'll have a flexi secton at the front between the DP and the cat. The cat will be 200 cpi metallic and will be removable to be replaced with a straight through pipe.

2 x lambda bungs and an EGT bung.

2 x silencers as per the stock item, one in the middle and one at the back with twin tailpipes.

Stock hanging points will be used as much as possible.

The pipe will be oval at the front where it comes under the subframe and it will also be oval at the back where it goes over the axle.

It'd be easy enough to put a few v bands into it to make it shipable so my question is would anybody be interested in having one? I'm not after a committment to purchase but just wonder if anybody out there doesn't have a stainless system at this stage and is planning to buy + planning for bigger power.

Exhaust will not be loud, compared to many big bore straight through items.

Lead time could be 3-4 months, I have the DP almost completed.

Regarding the price, somewhere between €600-€1000, I don't know yet.

[david]

i'm interested in just the DP for Rs2.
how much do you reckon it will cost for DP only?

[QuattroFever]

i may be interested, what grade stainless will you do it in. 316L?

Will it be 3.5inch rolled to oval

[s2_wot]

i'm interested in just the DP for Rs2.
how much do you reckon it will cost for DP only?

DP is mandrel bent from one piece of pipe, I didn't even get an invoice for mine yet so I don't know. Out of interest would you have it in 3.5" round going under the subframe. I know my standard dp has a few war wounds as it is.

i may be interested, what grade stainless will you do it in. 316L?

Will it be 3.5inch rolled to oval

I'm going to go with 304ss from the dp back and not 100% on the material for the dp. I want to test one in 304ss because it's available and it's been used on numerous occasions. The 316L or 321 is also available but the machine isn't set up for it, Time ~ Money etc.

The oval will be fabricated to have the same internal area as the 3.5" diameter by splitting a 63mm pipe in half and welding in the flats in a jig, I've been working on that for a while. The 1st section I made was in mild steel and it flowed (ambient air test) within about 2% of the 3.5" round. The oval will be flow matched so it may have an internal area of 3.55" if you get my drift.

[terrybullwon]

I would love to see a picture of the down pipe and how it clears the cv and sub frame and retains ground clearance, I'll swap you some photos of length I had to go to fit 102mm

[s2_wot]

I would love to see a picture of the down pipe and how it clears the cv and sub frame and retains ground clearance, I'll swap you some photos of length I had to go to fit 102mm

That's the challenge, if it wasn't nigh on impossible I wouldn't even try

EDIT: will get a few pics up at some stage soon, I've loads taken but it isn't finished.

[QuattroFever]

I'm going to go with 304ss from the dp back and not 100% on the material for the dp. I want to test one in 304ss because it's available and it's been used on numerous occasions. The 316L or 321 is also available but the machine isn't set up for it, Time ~ Money etc.

The oval will be fabricated to have the same internal area as the 3.5" diameter by splitting a 63mm pipe in half and welding in the flats in a jig, I've been working on that for a while. The 1st section I made was in mild steel and it flowed (ambient air test) within about 2% of the 3.5" round. The oval will be flow matched so it may have an internal area of 3.55" if you get my drift.

I get ya. Good stuff!

...and mmmmm one peice mandrel bent DP. Are you sand loading to bend it? I've always wanted to do it that way myself but i'm too frickin lazy.

I would love to see a picture of the down pipe and how it clears the cv and sub frame and retains ground clearance, I'll swap you some photos of length I had to go to fit 102mm

[Error404]

If this will be S2 / RS2 K24 fitment I'd be interested in just a downpipe dependant on the fit & clearance around the cv / subframe as mentioned above

[s2_wot]

I get ya. Good stuff!

...and mmmmm one peice mandrel bent DP. Are you sand loading to bend it? I've always wanted to do it that way myself but i'm too frickin lazy.

I found a man with access to a machine with the proper insert for bending. The radii are a bit bigger than I would like but on the upside they're very good for flow. We'll see how it goes. There's a bit of interest that's good.

[jade]

I would be interested in a downpipe no flanges no wastgate tube, depending on lead time as I am just about ready again !

[G60Rallye]

Good luck with getting the exhaust built. For the work it took with mine a £1000 would be cheap! How are you going to do the transitions from oval to round?

[s2_wot]

Good luck with getting the exhaust built. For the work it took with mine a £1000 would be cheap! How are you going to do the transitions from oval to round?

I made a template with some cardboard, drew up the resulting shape and played with a manual bending rolls and some 1.5mm galv for a long time to come up with something close. I was trying to make it from as few parts as possible but I think now there'll be 8 per transition. I think getting that clearance in that area will be worth the hassle. Not finished by means.

[Rocco]

we want pictures Shane¡

B4 avant and sedan chasis too ??

[david]

[QUOTE=s2_wot;541055]DP is mandrel bent from one piece of pipe, I didn't even get an invoice for mine yet so I don't know. Out of interest would you have it in 3.5" round going under the subframe. I know my standard dp has a few war wounds as it is.

i think 3.5" round will just make it past the subframe if bend correctly,otherwise you'll have a battle on your hands fitting it
round tube will be my first option though.

[terrybullwon]

Good luck with getting the exhaust built. For the work it took with mine a £1000 would be cheap! How are you going to do the transitions from oval to round?

Here here.

My 102mm flexi was near on £120 and then cost of the V-bands, SS tube and boxes .

And to top it off to get my down pipe to fit i used a 30 ton press to change the shape of the tube to clear the CV boot