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So after a long 6 weeks here is the finished result, these will be on sale for around £200-250 prices to be confirmed.

But my oh my they look good very excited to get them on the car 100x more ridged then the stock pipes so this should help with pressure drops and swelling of the stock hoses.
Big thanks to Forge for developing these with myself and Ian H.

Same sizes as stock I take it

Looks good! Same size as stock, pretty easy to fit too once the under-tray is off but a access to a smaller set of hands may be an advantage to the top of the IC (one end of the "Ribbed for her pleasure" pipe).

Tom - I forgot to ask at the time but can I assume they come in the usual variety of Forge colours?

On a price point they do seem Quite expensive for what they are if I am honest

Unfortunately there's only two companies making these (Forge & KWE) so unless other companies start making these and bringing some competition (which is what I was hoping would happen between Forge/KWE), the price will remain the same.

I have a source that I can get silicon hose made up for probably not much money, last time I checked tooling was about 250 dollars then cost per build depends on the spec you Build it too

"pressure drops and swelling of the stock hoses"

I am shamefully unaware of this. Where does the pressure drops ocurr (explain or show on dyno) and what's the issue with swelling hoses?

Not taking the piss, just unaware.

This is my understanding which may not be 100% accurate but here goes (figures picked at random as an example) -

The turbo is trying to create a set level of boost pressure at the engine intake but because of all the OEM pipes & intercoolers there will naturally be a drop in pressure between the turbo and the intake so the turbo must create a higher boost level at the turbo to take into account those loses i.e. If the engine needs 1BAR of boost and there is a set 0.2BAR pressure drop in the system from the intercoolers and pipes (say 0.1 from the intercoolers and 0.1 from the pipes) then the Turbo will have to create 1.2BAR of boost to allow for the drop. Now that's fine if the Turbo wastegate (via electronic Boost Controller or ECU) is allowed to run 1.2BAR however if the amount of boost the turbo can create is limited by the turbo itself, the cars ECU or a Boost Controller to only allow 1.1BAR then the engine performance will be lower as the 0.2BAR pressure drop is still there so it'll only be getting 0.9BAR instead of 1BAR.

So if you can reduce that "constant" pressure drop of 0.2BAR to something lower it will allow the Turbo to run less boost, which is better for the Turbo and less boost also means the air temps won't be as hot. As the pressure drop caused by the intercoolers can't be changed without replacing them (at great cost) the only thing left is the pipes. Now the thin OEM rubber pipes on the RS6 are quite soft when warm (and the engine is stupidly hot!) and when you make rubber warm it becomes softer so when you mix a warm, soft rubber pipe with pressurised air what happens is that the OEM pipe expands slightly (swells). If you expand a pipe which has a set amount of pressure in it then the pressure drops so if you can stop the pipe expanding then you remove the pressure drop they cause.

This is where the Silicone pipes come in as they don't expand under heat & pressure meaning there will be no pressure drop, so now our 0.2BAR pressure drop has been reduced to leave only the 0.1BAR drop created by the intercoolers, with all those benefits mentioned above. As a bonus, if you've now reduced your pressure drop you now have the option of turning the boost back up 0.1BAR giving you the potential to increase engine power. Plus they are less prone to damage/splits, better for heat control, and look better than OEM.

So thats my understanding of why Silicone pipes are a benefit. I'd say they wouldn't make any performance difference on a stock car but they may allow a stage 2 car to either run a little less boost at the turbo (better for the turbo) to run the same amount of boost at the engine (less drop) or alternatively, run a little more boost at the engine (more power) for the same amount of boost at the turbo. Now what those figures would be I've no idea as I don't think anyone is running silicone pipes on a stock or stage 2 car yet.

Hope that wall of text helps - again those figures above are just picked at random to give an example, I've no idea what the actual pressure would be.

You should eat that banana before it goes off. Or is destined for a smoothie ?

Cheers Ian,

Edit: Updated my post. Read your message again, in detail.

I believe that the friction created in the IC tubes, together with the rubber expansion, will have minimal impact on the boost pressure... if even measurable. (I'd be happy if someone can prove me wrong here!). Please note: prove me wrong on OUR cars. I know other cars have issues with pressure drops that can be remedied. But remember we have (relatively) large ID tubes, and they are (relatively) short as we have 2 SMICs close to the turbos instead of TMIC or FMIC - which require a lot more tubing, often with bends building up additional friction.

When it comes to the temperature - yes certainly silicone has very low thermal condictivity - meaning that the charge air will be (slightly, possibly measurable) cooler than with stock rubber tubes - which is good.

I'd love to hear a sales pitch from the manufacturer, hopefully backed up with some data. (Which in the end could possibly motivate me to purchase these tubes... which are.... quite... expensive.... thb... )

Edit: What I'm saying is this: There is absolutely nothing wrong with these tubes - they will improve your car's performance. But how much/little? A brief cost/benefit analysis, for me, today, tells me it's not worth it. I'd love to be proven wrong.

To the questions about improving power, this is something that will have to wait until i can get a dyno run before and after with the new hoses fitted.
This was a gamble in contacting Forge to see if they'd work with us making the pipes, as we obviously supplied the pipes and they gave us "test" samples etc i had no idea what the cost was going to be until the marketing was done.

Obviously if i was on the flip side id want some evidence too, but time will tell as no tests have been undertaken yet, so i will update as this information becomes available.
My main reason for the silicone route was simply after squeezing my bottom boost pipes whislt under the car i realised that they were horrifly soft and just looked old and worn, i didnt want to spend the silly money on oem rubber pipes as this tallies well over £300.
So the next route was to look into silicone hoses which was found and done, and being honest they look a hell of a lot better than oem and if they help with lowering the pressure drop (no matter how small) and bring down the intake temps thats fantastic, but as said my main reason for this was to replace my oem pipes with something that would actually last and would cope with any possible increased power in the future.

Well put! Will look forward to any update!

Ungjaevel wrote:Well put! Will look forward to any update!

Hopefully some good news, i need to find a local dyno that will let me do a same day run and let me swap over the pipes to try and keep things as accurate as possible,

Just a quick update of prices from Forge, these are now £155 so around £80-100 cheaper than others - http://www.forgemotorsport.co.uk/Silico ... -1498.html

Well done Guys. A positive is that these can only be better than the originals that will deteriorate over time (normal for rubber). At £159 they are well priced given the design and materials and I guess cheaper than the OEM equivalent? From a preventative maintenance perspective they are a good option.

Many years ago I helped develop and re-design the silicon intake hoses for the TVR Cerbera 4.5 AJP engine, these were a different design to the OEM version and there was 8 of them (whirlwind induction hoses), price wise they ended up at £500 a set. They sold like hot cakes!

Well done Guys.

Julian