Engine Upgrade - Factory Restrictions

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
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RS6...
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Engine Upgrade - Factory Restrictions

Post by RS6... » Sat Apr 23, 2011 6:36 am

Gents,

I am embarking on a semi-major uprgade of my '6.

I have done much reading and researching and the general consenses is that the exhaust/turbo manifolds and intale pipe become a restriction at ~600hp.

I would like to know who has actually found this to be the case in practical testing ie flow testing? Or if anyone has upgrade turbos etc and then changed the manifold to gain 50-100hp gain without any other change?

I would also like to know if there is anyway to modify them to increase flow or is the only option to fabricate new units?

Thanks in advance and Happy Easter to all!

RS6...

Ceveman73
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Re: Engine Upgrade - Factory Restrictions

Post by Ceveman73 » Sat Apr 23, 2011 11:11 am

You asked this before mate. Speak to MRC, they have lots of experience! :)

Cheers,

M.
C6 RS6 Plus with a few sensible mods...

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Re: Engine Upgrade - Factory Restrictions

Post by RS6... » Sat Apr 23, 2011 1:07 pm

I have asked again because I cannot get a definitive answer.

Also MRC I am sure are helpful but I dont want to hassle performance shops directly as they have spent time and money learning things, if they are willing to reply that would be great.

I am also interestd to hear the thoughts of other '6 owners who have gone down this road even thought I am sure it is very few....

Thanks for taking the time to reply thought mate!

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posterboyj
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Re: Engine Upgrade - Factory Restrictions

Post by posterboyj » Sat Apr 23, 2011 3:10 pm

I would;

Hybrid turbos or single Garret GT40 Turbo (custom manifold required)
Upgrade Turbo down pipes
Manifold is optional, rather port the manifold to increase the exhaust gas flow
upgrade intercoolers or custom front mount intercooler

Upgrade turbo intake

Custom remap + gearbox remap
Cornishmoocher wrote:Buying an RS6 and then worrying about the fuel consumption is a bit like buying a boat and worrying about getting it wet.

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Re: Engine Upgrade - Factory Restrictions

Post by paulm846 » Sun Apr 24, 2011 10:17 am

buy mine, its on pistonheads. 778ps, and manual

Paul
c6 rs6

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Re: Engine Upgrade - Factory Restrictions

Post by RS6... » Sun Apr 24, 2011 11:45 am

Where is the fun in dong that paul?.... :)

By the why you selling and have you got any performance figures from it?

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Shoppinit
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Re: Engine Upgrade - Factory Restrictions

Post by Shoppinit » Sun Apr 24, 2011 11:55 am

All the pleasure, none of the headaches! And probably a lot cheaper, too. You'd spend that much just on the mods - without the car.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
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Re: Engine Upgrade - Factory Restrictions

Post by RS6... » Sun Apr 24, 2011 11:57 am

Can we please stay on topic?

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Shoppinit
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Re: Engine Upgrade - Factory Restrictions

Post by Shoppinit » Sun Apr 24, 2011 11:59 am

RS6... wrote: By the why you selling and have you got any performance figures from it?
You stay on topic.

Good luck with your mods.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE | RR Classic V8 flapper
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

bam_bam
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Re: Engine Upgrade - Factory Restrictions

Post by bam_bam » Sun Apr 24, 2011 5:10 pm

shoppinit wrote:
RS6... wrote:Where is the fun in doing that...
All the pleasure, none of the headaches! And probably a lot cheaper, too. You'd spend that much just on the mods - without the car.
Ahhhh, I see where he/she actually asked to go off topic...

You're limited by the amount of torque the 'box can handle and there's very few ways to get around that issue (man conv being the best workaround). Paul's manual conversion is running 778PS and enough torque to tear the fabric of time, it's the ultimate RS6 with almost everything custom fabricated. Whatever you do it'll not better Paul's example.
Another nice one is RS6_Dave's - take a look at the spec to get an idea of what a C5 can do on std manis and std blowers.
No matter where you go, there you are.

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Re: Engine Upgrade - Factory Restrictions

Post by RS6... » Mon Apr 25, 2011 4:15 am

The driveline issue has already been resolved.

I am simply asking for people experience but I appreciate your reply.

With regards to Pauls car I am sure it is good but I am not sure of engine specifications other than its bolt ons and power output nor do I know its torque/power curves or performance figures.

Thanks again for taking the time anyway.....

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JCviggen
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Re: Engine Upgrade - Factory Restrictions

Post by JCviggen » Mon Apr 25, 2011 7:12 am

RS6... wrote:The driveline issue has already been resolved.
Do tell us more. Information can be a 2-way road ;)

No offence but this is just one of those threads/projects that tend to go nowhere in the end :)

If you want to do this properly you are looking at investing significantly more money than the value of the car, as Shoppinnit already remarked. Basically you'll be burning a lot of money that will never be recovered if you try to sell it, so you need to be up for that.
Also, do not try to re-invent the wheel. Many knowledgeable people have spent a lot of time and money understanding what works and what doesn't, and you can't just come along and think you'll be able to improve on whatever they came up with without using their experience.
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Cornishmoocher
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Re: Engine Upgrade - Factory Restrictions

Post by Cornishmoocher » Mon Apr 25, 2011 7:18 am

RS6, In your original post you have asked if anyone has done practical testing on BHp v stock manifolds.
People have given you their valued opinions based on our experiences.
As you rightly say on stock manifolds the restictions will hinder large outputs- we know this, we have been around these cars for a long time, we also know that to get reliably over 550hp not 600 you need to go big turbos AND manifolds. Although I know a few cars have made 550+ under certain circumstances on stock. We also know that "bolt on" bits are pretty good at increasing power... rather than magic ingredients and Stickers.
There are people who have done practical testing, Paul being one via MRC, and a few others via unit 20. And I feel the very fact that these people have not responded to your question is telling you something.
Any tuning house that reckons they can get 600hp from an RS6 without manifolds is either A) Lying, B) need to invest in an accurate dyno or C) be in America
I too am slightly perplexed at the goinig off topic comment, strawberry bird table ash cloud.
It's all Bollox.
Half of what you read is bull and the other half is all <beep>.

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Re: Engine Upgrade - Factory Restrictions

Post by bam_bam » Mon Apr 25, 2011 10:37 am

RS6... wrote:The driveline issue has already been resolved.

I am simply asking for people experience but I appreciate your reply.

With regards to Pauls car I am sure it is good but I am not sure of engine specifications other than its bolt ons and power output nor do I know its torque/power curves or performance figures.

Thanks again for taking the time anyway.....
Wow you sure are endearing yourself well on this forum! That's a handy gift you have, and probably best summed up in the username you've chosen - RS6 with ellipses isn't going to get annoying at all, is it?

Why don't you start out by telling us where you're located, how long you've had your car and what you plan on doing with it. Your budget would be interesting too. Since you've said this is only "semi-major" upgrades, that means 'no engine pull' to most people on here i.e. Intercoolers, filters, Milltek and a remap.

If you wanted to see Paul's power and torque curve you'd have found it by now, it wouldn't be hard to find on MRC youtoob postings. Also, I wouldn't really call that car's modification list 'bolt-ons', as I said, there is a lot of one-off fabrication to accommodate those GTs.

I think one of the best case studies for low power output due to standard manis is Amanda's engine. Her car is a work in progress and she might get upset at my assumptions, but with LO650s, thicker head gaskets, Loba cams, no-CAT downpipes and a Viper MAP (amongst other things). The HP output is considered a little low, I'd like to think this is due to the std manis, but I could be wrong, it could be the injectors and fuel supply. Although I don't think fuel and injectors become an issue until 600+.
No matter where you go, there you are.

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Gravitypilot
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Re: Engine Upgrade - Factory Restrictions

Post by Gravitypilot » Mon Apr 25, 2011 11:23 am

Paul, just seen the advert.. 40k car, 1 picture? I might be interesed in this but need to see much more and videos, the last car i sold had a few videos walk around car engine start and running maybe in car footage?
03 Mugello Pearl Avant 32K
MTM Tuned, Vreds, Miltek 520+ :-)

Need any parts? just give me a shout on PM

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