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D2 - Fuel and Exhausts Everything to do with getting fuel into the engine, and fumes back out again

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  #11  
Old 23rd October 2016, 04:52 PM
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Goran Goran is offline
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If anyone else goes for a X before the cats, try to get it made to look like this one. I spoke to one of the designers of this pipe for a Porsche 928 (also a V8) and he says the crucial elements are the wide entry angle of the exhaust from downpipes, the narrow exit angle before the cats, and the size of the crossover and the distance from the header.
He found moving the X just a few inches forward or back lost some of the power gains.

Of course I have no idea if my X is in the right spot as it was not placed based on dyno testing.





http://rennlist.com/forums/928-forum...pping-now.html

http://rennlist.com/forums/928-forum...sale-sold.html
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Last edited by Goran; 23rd October 2016 at 04:55 PM.
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  #12  
Old 25th October 2016, 12:41 AM
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27litres 27litres is offline
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Excuse my ignorance Goran, if you've posted something on this before - though I did just go back through a lot of your old threads.

Judging by your exhaust pictures, your gearbox looks to be a manual.

As it is UK registered, I'm assuming it's RHD (I know that's not strictly necessary in the UK).
So do you have a conversion thread?

What pedal box was used to add the clutch?
What master cylinder was used to add the reservoir the clutch system etc...??
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  #13  
Old 25th October 2016, 01:51 AM
ainarssems ainarssems is offline
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He bought factory manual LHD from Germany IIRC and imported it.
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Last edited by ainarssems; 25th October 2016 at 01:56 AM.
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  #14  
Old 25th October 2016, 09:39 AM
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Goran Goran is offline
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Quote:
Originally Posted by 27litres View Post
Excuse my ignorance Goran, if you've posted something on this before - though I did just go back through a lot of your old threads.

Judging by your exhaust pictures, your gearbox looks to be a manual.

As it is UK registered, I'm assuming it's RHD (I know that's not strictly necessary in the UK).
So do you have a conversion thread?

What pedal box was used to add the clutch?
What master cylinder was used to add the reservoir the clutch system etc...??
Yes I gave in and sold my RHD S8 to buy a LHD manual
The RHD to manual conversion is not dead yet though, I gave my converted pedal box model, and pedal to fit RHD manual to Mike, the most recent news I heard is that he took it to his machinist who is going to make the custom pedal box. I gave him the master cylinder too, which is just a stock Audi A4 metal master cylinder. The pedal box is just a stock RHD A8 or S8 pedal box. It has plenty of room on the pedal pivot shaft for a Clutch pedal. My design is simply an additional aluminium casting or machined part to bolt or weld onto the stock RHD pedal box so that a factory master cylinder like the A4 cyliner can be used for easy replacement.

Here is the thread with some pictures of the wooden mock up pedal and master cylinder bracket. The pedal would need to be changed a bit to give more room for the foot where the rubber pad is. The stock LHD pedal is an aluminium casting so there is no problem to machine the RHD clutch pedal out of aluminium.

http://forum.a8parts.co.uk/showthrea...=pedal&page=10

Last edited by Goran; 25th October 2016 at 09:49 AM.
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  #15  
Old 25th October 2016, 10:08 AM
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Borys Borys is offline
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Welds look invisible, wow
Unfortunetaly when custom exhaust drones nothing much can be done about it.
It all up to silencers used. To fix this it will be a trail and error with different box sizes.
Been there, spent a lot of money to get it right but in the end went for original boxes at the back and drone was gone with perfect sound too
Cannot post here ha ha as I'm talking AMG
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  #16  
Old 25th October 2016, 10:31 AM
HPsauce HPsauce is offline
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Wasn't there a discussion about adding a Helmholtz resonator to control the drone?
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2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
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And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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  #17  
Old 25th October 2016, 11:05 AM
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Borys Borys is offline
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Yes it cures it
i reckon with the OP's such a nice set up would be a sin to modify now.
If I would ever go custom again it would have to be design with resonator before it goes on a car, so is nicely blend in to look like it meant to be there
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  #18  
Old 25th October 2016, 12:05 PM
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Goran Goran is offline
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Quote:
Originally Posted by HPsauce View Post
Wasn't there a discussion about adding a Helmholtz resonator to control the drone?
Spot on HP, that's what I'm planning to do, go back to the guy and ask him to fit Helmohltz resonators to each pipe at the back (starting just in front of the rear silencers and pointing back) and try to angle them so they aren't visible from behind. I did a bit of reading about them and the rpm resonance range vs length, so I'm thinking to ask to have them variable length and jubilee clipped so they can be tweaked. I'm going to guess 31" length for the initial try.

I am guessing its something to do with the resonance of the whole exhaust and its length and shape, and its temperature, because the drone is much less pronounced on cold start, but 5-10mins later when it warms up, in the same 1500-1900rpm range the drone appears.

Last edited by Goran; 25th October 2016 at 12:08 PM.
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  #19  
Old 25th October 2016, 12:42 PM
HPsauce HPsauce is offline
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Those pipes to the rear silencers are already different lengths so may be (more likely are) resonating differently already. Interesting challenge.
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2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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