Heatshield and GruppeM including cold air feed Development

[sonny]

Think i'll stick with my standard air box then with CAF, was thinking about upgrading to a gruppe M to see if I could get more. Maybe wrapping the standard air box would make more sense. I got the following with only stage1 manifold CAF and full milltek no cats.

[img]http://i1084.photobucket.com/album ... .jpg[/img]

Very good results,esp as you have the standard cats. What time of the year did you do the run?

I did think about wrapping the underside of the oem air box (part that's closest to the exhaust manifold).

I will mention that the valves was not clean when the run took place.

[thedoluk]

I have no cat Milltek DP's not OEM. 18th Jan top left of the print out, was pretty chilli. Thou ambient temps should not matter I thought as it is corrected?

[sonny]

Just seen date, well the ambient air will be cooler so lets say it was 10c, intake temp prob around 20c, correction is est from wheels power (iirc)

Ok so your cateless, explains it, very good figs. Have you put a sound meter to your exhausts, as im curious to see what the read out is for he catless exhaust

[thedoluk]

I've not measured the sound, I've got res Milltek valved with the valves disabled now as not that loud. Just sounds like sweet music, especially the pops on over run. Tempted to try non res like Doug but think it might be a step too far.

[kiwi_mtm]

Are those dyno runs done in 4th gear ?
Would there be much of a difference if they were run in 3rd ?

[adsgreen]

In theory they would be the same however the lower gears have more chance of causing tyre slipping on the dyno throwing off the measurement

[P_G]

Temper that with the maximum speed of the rolling road, often 4th the RS4 exceeds the maximum measureable roller rate which is why some roads do runs in 3rd.

[RSKiwi]

This is all interesting reading, good figures too sonny. The OEM airbox possibly being better in certain conditions is especially interesting. It is a real shame as the GruppeM has a sound that scares children and would suck to remove. Any pics of the cold air feed MRC put in? When I was there they hadnt done one for a GruppeM and needed to work out how to fit it in effectively and its next on my list.

Again good work sonny, all the effort definitely helps increasing the pool of knowledge on here.

[sonny]

I think there done in 4th, certainly sounds it.

RSkiwi, thanks fella. If you could rework the GruppeM filter, maybe fabricate some more CF making the filter housing more round at the base and directing it toward the air source then this might be the option(and only real option). Other that that is to have a bonnet scoop directly above the filter to help expel heat. However there not everyone's taste and may create drag.

I think the OEM airbox with the 3 air sources including de-flapped and the cold air feed will be the best option. However you will lose the sound of the GruppeM and the throttle sensitivity (throttle blips are easier).

One thing I have noticed. in this recent hot weather and driving in stop start traffic, I can smell I plastic burning type smell. I believe this is the glue on the tape heating up. The tape is new and has not yet been exposed to very hot temperatures so will be interesting on my next track day (Castle combe 16th July).

[rs4head]

Thanks for the feedback, Sonny. Very interesting reading. I am off to MRC tomorrow for CAF, gut precats and remap. I am standard currently apart from milltek non res non valved. Can't wait to see what power/torque I am putting out currently (30k on clock) and what i get to....

[sonny]

Thanks for the feedback, Sonny. Very interesting reading. I am off to MRC tomorrow for CAF, gut precats and remap. I am standard currently apart from milltek non res non valved. Can't wait to see what power/torque I am putting out currently (30k on clock) and what i get to....

You wont be disappointed thats for sure.

[Steve_C]

Thanks for the feedback, Sonny. Very interesting reading. I am off to MRC tomorrow for CAF, gut precats and remap. I am standard currently apart from milltek non res non valved. Can't wait to see what power/torque I am putting out currently (30k on clock) and what i get to....

Will be interesting to see what results you get. Have you got an OEM air filter?

[rs4head]

I have a BMC filter as well - forgot to mention - so using that instead of MRC filter which would normally be used with CAF installation

[adsgreen]

Instead of a draggy and quite chav bonnet scoop, maybe a naca duct would help a not be so obvious.

I'd log the inlet temps on the road rather than on a dyno. Very few get real airflow through every where

[sonny]

Instead of a draggy and quite chav bonnet scoop, maybe a naca duct would help a not be so obvious.

I'd log the inlet temps on the road rather than on a dyno. Very few get real airflow through every where

Yes a naca duct, would never put a "proud scoop" on the bonnet, but in theoretical terms it would be a benefit.

I agree with you about on the road air temps, as we all know its better, a rolling road is just a interpretation.