Renich Carbon fibre Ram Air Duct

[Doug_S2]

IIRC correctly, Richards car with the dms map was dynoed at 412ish ps, when he had a previous dyno sheet for 470bhp from DMS? We couldn't find anything wrong as such that would have caused it to lose that much power so we put one of our maps on and it did 427 but with intake temps rising (becasue the gruppem was sucking in air from the aux rad that had opened the thermostat while the car had sat there for 40 minutes when we flashed the ECUs). When we cooled the car for 10 minutes to get rid of heatsoak and close the thermostat in the aux rad, it did 442ps.

The cold air feed is their to keep intake temps at a consistant ambient temperature. The gruppeM is particulary bad for this becasue it is not shielded underneath so you get heatsoak and it sucks in warm air - sonny helped this a lot with his shielding.

Any cold air feed is going to help and keep intake temps at ambient temps. If you want a ram affect I think you should block the top snorkal so the only air that can go in is forced in 1 inlet tract.

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i thought the idea of using a CAI on our motors was to do just that feed cold air(or cooler air) into the engine.
if CAI are adding bhp its surely just whats already been robbed due to the engine breathing hot air and retarding timing as opposed to say adding 20bhp through the effect of ramming more air in.

Yup, I agree - CAI isn't going to add any intrinsic power on it's own but rather allow the engine to maintain power for longer under hard use.

[P_G]

Doug, instead of a CAI do you think it is feasible to fit the RS5 twin air intake onto the RS4 from what you have seen of both cars? I have seen pics of one in Germany but never one since.

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Any cold air feed is going to help and keep intake temps at ambient temps. If you want a ram affect I think you should block the top snorkal so the only air that can go in is forced in 1 inlet tract.

Thats' another very good point - if you have an airbox with multiple sources of outside air then any ram effect (such that it is) would be lost as it would dissipate down the other feeds.

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Doug, instead of a CAI do you think it is feasible to fit the RS5 twin air intake onto the RS4 from what you have seen of both cars? I have seen pics of one in Germany but never one since.

Interesting - looking at some pics Audi have relocated the water header tank far to the left out of the way and they can do this as the separate airboxes (no doubt containing the filters) are slightly smaller. However you'd need an RS5 monifold as this has two intake pipes that look slightly narrower. You'd also need to mess about with the maf sensor as the RS5 still looks like it has one mounted on left intake but not one on the right so it must double it up in the ecu.

Personally looking at the work involved I don't think it would be cheap and wouldn't add that much.

[Rick_RS4]

RTS BRAT wrote:I kept the Vanes as removing them causes the sensors to error. They can't read the posistion of the vanes... .

Hmmm.... not strictly true. Keep the shafts and sensors, ditch the vanes.

+1, had this done on my car as well as other, remove the vanes but keep the shafts and sensors; if anything doing this means the shafts move more freely and no don't throw P2015 / P2020 codes as there are no vanes that stick.

ill be taking the inlet mani off mine in a few weeks is it worth removing those while its off? or is this a later along the line mod?

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might need a remap to make the most out of it but it'll only affect low revs.

[Rick_RS4]

might need a remap to make the most out of it but it'll only affect low revs.

ah ok thanks i might whip them off while its out then map it

[RTS BRAT]

IIRC correctly, Richards car with the dms map was dynoed at 412ish ps, when he had a previous dyno sheet for 470bhp from DMS? We couldn't find anything wrong as such that would have caused it to lose that much power so we put one of our maps on and it did 427 but with intake temps rising (becasue the gruppem was sucking in air from the aux rad that had opened the thermostat while the car had sat there for 40 minutes when we flashed the ECUs). When we cooled the car for 10 minutes to get rid of heatsoak and close the thermostat in the aux rad, it did 442ps.

The cold air feed is their to keep intake temps at a consistant ambient temperature. The gruppeM is particulary bad for this becasue it is not shielded underneath so you get heatsoak and it sucks in warm air - sonny helped this a lot with his shielding.

Any cold air feed is going to help and keep intake temps at ambient temps. If you want a ram affect I think you should block the top snorkal so the only air that can go in is forced in 1 inlet tract.

As Doug said when we dyno'd the car initially it did produce the figures mentioned above 412ps, but I must add a critical fact that has been left out.
When MRC added their map it didn't achieve any more on the dyno! At this point they decided to open the bonnet and then cooled the car for 10 minutes to get rid of heat soak and close the thermostat ... as Doug said. But we did not treat the car in the same manor when the DMS map was in the car. The bonnet remained closed and the car sat the Idling for around twenty minutes prior to conducting the first runs. So heat soak definitely have been an issue.
I don’t like the fact that we are comparing Tuners and maps... This was not the intention of the blog. The reason I went to MRC in the first place was to find out why I had lost so much power. I also have previous Dyno charts from DMS proving that I had previously achieved similar figures to those finally delivered by MRC.


The concept is simple, the denser the air the more power, the colder the air less retardation and reveal the true power. To prove the concept is easy take a funnel and cut the small end off so that it is the same size a peace of tube. Hold both out of the window in turn and see which has the most resistance. The greater the resistance the greater the air pressure must be. The larger the leading edge of the funnel the more air is forced into the same space. Try this at 40 and the confirm that Ram air only works at 120mph. admittedly the faster you go the greater the effect, as I stated at the beginning the fans on a dyno only spin at 60 mph.... This is the exact reason that when you tune a turbo car you have to ensure that it receives enough cool air to perform. If anyone purchases the Kit simply do two runs, one with the standard fan set up and one with a fan pointing directly into the duct. I know you will see a difference. On the road you won’t have the issue of air displacement as the air will be uniformly hitting the face of the car. In fact Ricks homemade version should prove the point depending on the shape of his duct!

[RTS BRAT]

It's the exact same as what we all have from Mrc a cai system but in carbon so I reckon the go faster carbon fibre has done it sorry for being a doubter but with cats etc in place it sounds bollocks to me. Btw I run 450bhp on a dyno dynamics rolling road and I've got a supercharger, they struggle to pick up the b7 torque split plus your dyno doesn't mention which mode you ran in ie shoot 44 centre diff etc etc I can dig out mine it tells you all of if, what was your afr reading also?

Danny you are not making any sense, Doug already confirmed that I got 442 ps on his rolling road with his map-. So it sound more like you have an issue with your supercharger!!

Simple question... isn't the whole point of modification to make the car better? Someone has to be first! I have the Cats, I have the vanes and I have the power...

[RTS BRAT]

It's the exact same as what we all have from Mrc a cai system but in carbon so I reckon the go faster carbon fibre has done it sorry for being a doubter but with cats etc in place it sounds bollocks to me. Btw I run 450bhp on a dyno dynamics rolling road and I've got a supercharger, they struggle to pick up the b7 torque split plus your dyno doesn't mention which mode you ran in ie shoot 44 centre diff etc etc I can dig out mine it tells you all of if, what was your afr reading also?

Danny you are not making any sense. Doug already confirmed that I got 442ps on his rolling road with his map. So it sounds more like you have an issue with your supercharger!!

Simple question... isn't the whole point of modification to make the car better? Someone has to be first! I have the Cats, I have the vanes and I have the power...

[sar]

"first",lol...

[Rick_RS4]

my duct is very smooth and conical lol like i said ill get some logs soon, buttheres no way its added 30 -40 bhp,

it seems to me that the first map was a little ott to make you smile on the drive home, do you have Vag Com? could you do some logs?

rolling roads can be as good or bad as the guy doing it wants, if he sets the loading to minimal you could walk away with a graph for 1000 bhp, and if the guy is doing the map its more reason to to make him look good.

im not having a dig, even at MRC 440 bhp is bloody good.

[lengster1]

Sorry to burst your bubble but your spec is old hat on here,I ran that level of tuning and power ages ago,you have a 440ps level of tune which is very good and transforms a standard car for sure but 470 it isnt,perhaps it is on dms dyno in which case we could all add 30ps,I think we are all very aware of the principles you are explaining as some like myself have been running these mods and more for some time.

[lengster1]

My point exactly Rick rs4,CAI doesnt add 30ps as initially suggested