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Over the past few months I’ve become concerned by the threads relating to oil/carbon build-up in B7 inlet manifolds. I've also been interested in SilverRS4 & Anto's threads about developing the inlet manifold to help increase airflow and performance.


As I plan to keep the car for the long haul, I wanted to be sure that everything was as it should be inside my engine as well as seeing what could be done to improve an already great car - further.


Not having the skill/experience /time/ knowledge etc to do this sort of work myself, I needed to find someone capable of doing it for me. Since I’ve been around the Audi scene, I’ve heard nothing but good things about MRC Tuning so got involved in a conversation with them around what could be done.


These conversations culminated in me dropping my car off at MRC last Saturday for a week of work, focusing on:


• Investigating and cleaning any build-up in and around the inlet tract
• Testing a ported and polished inlet manifold
• Improving exhaust flow
• Custom mapping all of the above into one neat package.


MRC wanted to approach the work as a development programme, so it was important to have an independent assessment of results as the week progressed. Surrey Rolling Road was chosen for this so I took my car there for a benchmark dyno before any work commenced where she came in at 390.4bhp.


With the maker set, MRC took the car to their workshop and proceeded to take off the original manifold, only to be confronted by quite a mess:


http://i10.photobucket.com/albums/a140/ ... 3437-1.jpg
http://i10.photobucket.com/albums/a140/ ... 3439-1.jpg
http://i10.photobucket.com/albums/a140/ ... 3441-1.jpg
http://i10.photobucket.com/albums/a140/ ... 3442-1.jpg
http://i10.photobucket.com/albums/a140/ ... CN3443.jpg
http://i10.photobucket.com/albums/a140/ ... CN3445.jpg


Although the build up looks sticky, this was only surface deep and underneath it was rock solid and baked on.


Around 10 hours and some serious elbow grease later the guys had managed to clean up all of inlet and valves leaving them good enough to eat your dinner off!:

http://i10.photobucket.com/albums/a140/ ... clean1.jpg
http://i10.photobucket.com/albums/a140/ ... clean2.jpg
http://i10.photobucket.com/albums/a140/ ... clean3.jpg


We plan to monitor any further build up in the intake by taking off the manifold in 1500 miles before sorting the problem once and for all.


With the valves cleaned, MRC continued by fitting a ported and polished inlet manifold they had prepared and headed off to Surrey Rolling road to measure the difference, firstly with just the stock map and then by applying their own custom map.


The results were:


http://i10.photobucket.com/albums/a140/ ... dman-1.jpg


Blue line – Car in stock form
Red line – Clean inlet, modded manifold, stock map
Turquoise line - Clean inlet, modded manifold, MRC map


So there it was the magic 414bhp with torque improvements to boot!


Buoyed by the good results the guys took the car back to their workshop and focused their attention on the exhaust. A day and a pair of free flowing downpipes later the car was finished and ready to go back to SRR to measure the final results – here they are...


http://i10.photobucket.com/albums/a140/ ... ective.jpg

Red line – stock car
Pink line – Clean inlet, modded manifold, stock map
Blue line - Clean inlet, modded manifold, MRC map
Green line - Clean inlet, modded manifold, free flow downpipes & MRC map


At this point it’s probably worth reminding everyone SRR is completely independent to MRC and has no interest or benefit in artificially inflating these results.


To say I am pleased is an understatement. The car is noticeably stronger all over the rev range and much more responsive than before with increased torque that almost feels like a mini turbo has been bolted on – oh and the soundtrack


I’d like to thank Anto, Silver & Caldy for your help and advice along the way, but most of all I would like to thank Lucas, Doug & Minea at MRC for doing such a great job. They are a top bunch who are true enthusiasts and will be the only people to work on my car from now on.


MRC will be launching their new website in 2 weeks or so and will be featuring my car and all that was involved in a step by step blog. I’m sure they will do a far better job than me in detailing the work but in the meantime if anyone else is interested in following a similar path, give them a call – you won’t regret it!!

Thanks for the write up, it's great!

Could you give us an indication of what the cost would be for this work? What miles were on your car before you had this work done, and do you still have any warranty on your car? I'd like this kind of work done to mine but dont want to invalidate the warranty.

How do you find it to drive now?

Thabnks again for that blog, very handy.

Nice one, look forward to seeing it at the RR day

Awesome work!!

Glad you are happy with the results Rob. What do you mean by free flow down pipes; cat-less, gutted?

defo looks a good job rob... you say you are going to put 1500 miles on, then look inside again. are you going to give it the wynns treatment during that time to see if it does stop the build up of the jank. because we know by caldys there was a lot of jank on his with 3k on her. so we will be able to see if the wynns stuff actually helps to or prevents the jank build up... surely the best time to see if it does what it says on the tin

Nice work. Thanks for the great write up and something I think should be of interest to all of us.

Thanks for the comments guys, to answer a few questions the car is a 56 plate with 19,000 miles on the clock and up until now has been fully serviced by Audi in accordance to their service schedule.

As for using Wynn's in between now and opening her up again - probably not. MRC have a plan to stop the buildup from occurring in the first place so we will be sorting that next time they have the car, and we are keen to see how quickly it builds up so won't want to help it inbetween.

How does she drive? I’ve just come back from an early morning drive where I found myself laughing out loud at certain points! It's only now I have driven her on roads that I am familiar with that I have properly noticed the difference.
The engine no longer feels like a lazy V8, instead is now aggressive and very responsive with much more torque , the drone famous milltek drone at low revs has gone and part throttle driving and fuel consumption is the same as it ever was.

I've attached another graph which is a little less busy than those above showing before and after performance. I have gained up to 50bhp iand 40ftpd of torque in places over the rev range - not bad for an N/A engine!!

http://i10.photobucket.com/albums/a140/ ... esults.jpg

I love my car

And the best thing about the car?

It pops and crackles on the over-run which is great in tunnels.

You didn't mention how many old men in Surrey you scared Rob...

Fantastic !! Will in the future follow your lead in this , on the exhaust side did they bypass the cats or fit free flow ones? How much is this costing?

grats on the car... id be interested to know how much this costs, happy to get an idea on a pm if prefer

Well that explains why our cars have never made the manufacture performance quotes, so it seems there is light at the end of the tunnel then for us. I will def be looking into this at some point, even with out the free flow exhausts, 414bhp is impressive. have you got a sports filter on or induction kit, or was that with std air box?

Will be interesting to see how much they charge for the package upgrade

I have just dropped MRC an email, despite being 3,500 miles away I really hope they can help me out with the same superb results as you have experienced.

I am really interested to hear how they plan to resolve the intake buildup occuring.

From the comments already received on this thread I reckon MRC could be onto another 'winner' here with this package.

Very interesting post. When you have done the 1500 miles or so are you going to put it back on the rollers? When I used to mess around with mini's, the engine builder I used told me that the engine only starts producing real power when everything has sooted up a bit as this aids heat transfer in the engine.

At least we now know where the oil these engine drink is going..

Good result Rob .. well impressed ..

You need to put at the end



Did MRC write the map while on the RR ?




They did a good job cleaning it