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Discussion Starter #81
Can't do that i'm afraid, the V8 comes right up to behind the seats and i don't have a spare anyway, there is no spacesaver i can carry that will fit over the 325mm rotor,Porsche 996 caliper combo :)
 

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Discussion Starter #84
Thanks, there are a ton of little features like that on the car, most of them done out of necessity rather than styling.
 

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paul woods said:
Here is the Audi box in place, i have removed the tail pipes, these will have to be rerouted behind the box, down and out the rear, a bit of fancy pipe navigation and flanges will do it, and the actuated valves will be staying, they're pretty cool and will help with low end torque... yes cos that's the one thing i need more of :D




So the boot is now totally dedicated to exhaust, bang goes my small storage area, oh well!
very McLaren F1-ish!
 

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Discussion Starter #86
Today saw some good progress made on the new exhaust system, just to recap, i'm fitting an R8 rear silencer to get this thing sounding more like it should, the old TVR system was just deafening.

I made a mounting bracket for the R8 box and bolted that to the gearbox, the system moves with the engine so no need for flexi sections. Next i cut off the Audi V-band clamp and i tacked on the new V-band clamps complete, then made fresh sections to go from there to the manifolds, everything is just tacked for now.



Once the inlet pipes were made i started work on the outlets, tricky little buggers these, one pair has a vacuum operated butterfly which is normally open with engine off, and shuts when the engine runs on full vacuum at idle, this means as the load rises and vacuum drops these valves will open up gradually bringing the other pair of exhausts into play. Or i could snap them open with a VSV running from a programmable output on the Vems, so basically i could decide when the valves open, but i think i'm going to leave them plumbed straight to the manifold.

The bottom pair of outlets are just straight out, so i just needed to kick these 180*...





The symmetry here for me is important, it bugs the ____ out of me if one side doesn't look like the other, so i spent ages telling Jay how wrong he was :)

With the bottom two pipes done i did the top two with the actuators on them....

 

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Discussion Starter #87
I've staggered the overlap between the top and bottom pipe to make seam welding them easier, it also looks better.





This thing is fast becoming nuttier than squirrel ____, but i love the madness of it all.



From this position both pairs of pipes need to go straight down, have flanges put on them for three reasons...

1) Easy removal of the whole system later on if need be
2) I can change tail pipe design in future as the mood takes me
3) There is no 3, 1 and 2 were good enough reasons.

The next time i work on it should see the tailpipes tacked in position and i can start seam welding, we're looking forward to hearing it!
 

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Discussion Starter #88 (Edited)
A nice diagram showing the stock R8 exhaust setup versus mine, practically identical pipe lengths from engine to silencer, loving what's going on inside that silencer too, should sound exactly like an R8.



Actually after studying that silencer in detail it's quite a work of art, at idle and off load with the flapper valve shut the gases are forced to take this route and have to enter every chamber within the system before exiting just one of the tail pipes, it's a very complicated exit path...





Now under load with the flappers open the bulk of the restriction is bypassed, some gases are still going into all chambers but there is a direct route out...





No wonder they sound so quiet at idle and howl on full chat, lovely stuff.

EDIT: It looks like both catalytic convertors are built into the rear silencer...



So it will pass any emissions thrown at it, or i could remove them by cutting open the chamber they are in, taking the CATs out and welding in straight pipes instead. The only problem there is that if it ever does need to meet stiffer emissions regs i would need to buy a new rear silencer, which i really don't fancy at ?3500 a pop!

I think i'll keep them in there.
 
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hmm, probably you'll be covered for performance on this build. not sure if a decat is worth it - lol :)
 

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Its going to have a sound/character of its own, as the engine itself determines much of what a car sounds like. I'm really curious!
That's great tech... it made me consider working something out servo-related to give me a quiet mode, since I'm going to 4"... but I think I'll wait and see how loud it is before I start down that road :).
 

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Discussion Starter #92
Not exactly the same 4.2 V8, the R8 is a much more powerful version, but both 4.2's so my thinking is they should be moving very similar amounts of gas at idle/low loads.
 

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Discussion Starter #94
Ok i had to Google that engine as i'm not up on my Scoobies, my first words were Fuuuuu****k! look at the width of that thing...



If it bolts to something like an Audi trans and fits within the chassis rails then yes that'll go.
 

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paul woods said:
Ok i had to Google that engine as i'm not up on my Scoobies, my first words were Fuuuuu****k! look at the width of that thing...



If it bolts to something like an Audi trans and fits within the chassis rails then yes that'll go.
The Subaru trans is almost identical to yours. All the modern ones are AWD but they do make a rear driveshaft block off plate and something that eliminates the center diff. I have been daydreaming about this swap for a while now.
This is the engine I want. EZ36 3.6 liter
260ps (191 kW) @6000 rpm, [email protected] rpm


Good point on the width though lol. Might not be a bad idea to measure between the frame rails.
 

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Discussion Starter #97
Today saw more exhaust work, making this R8 system exit out the back of the car has been tricky to say the least, but it's finally done. Jay and Phillis were on hand to help me align the quad pipes, it was a right nightmare getting them all in line as i needed to make double sweeping bends to get from the silencer outlets to the bumper, a total of three 90* bends and two 45* bends per tailpipe.

Work started by taking the outlets down to the old boot floor, and adding flanges to them, these flanges allow the tail sections to be separate and changed in future if needed.





From these flanges i made the tail sections...



With the whole lot fitted it looks like this...



Almost mm perfect alignment, made possible by Phil and Jay using a pen to get the gaps between the tails and a Costa coffee stirring stick to get them level! I wanted to sight it all up but they insisted on using their patented Pen Alignment Nano Technology System, or PANTS! as it's known, couldn't have done it without them so thankyou chaps.

With the system fabricated i removed it all for seam welding, i only got as far as seaming the tailpipes but here is the rejigged R8 silencer just before welding...



So as soon as the system is fully welded i'll get to hear what she sounds like.
 

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paul woods said:
It looks a heavy sucker though?

Just numbers I found posted on the internet but what I found for the EZ36 is 104 kg. Compare that to the 2GRs 174 kg on Wikipedia and things are looking pretty good.
The EZ36 is rated at slightly less HP at around 256 and it's new enough it's peak HP potential isn't known and probably not quite that of the 2GR but it's low weight, COG and north south configuration make it a winner in my mind.


That exhaust looks beautiful. I love the tips.
 

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Glad to see then progress Paul. Looks good. I personally don't like square exhaust tips. For me, I prefer round slash cut tips. They have the old school look that fits the MK1.
 

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scottgas said:
Glad to see then progress Paul. Looks good. I personally don't like square exhaust tips. For me, I prefer round slash cut tips. They have the old school look that fits the MK1.
I would generally agree with you but the way these tuck up under that particular bumper looks pretty good to me.
 
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