We just weighed one of the completed intakes that is heading off for a special finish and so I quickly put everything on the scales. Here is the break down on weight of the RIS.

Stock plastic "lid" that is removed from the stock set-up weighs - 1.75 pounds
Complete Pressurized filter box that replaces the stock "lid" - 2.75 pounds

The factory "grill" that is removed from the scoop and the insulation piece that is removed from under the hood weighs - .5 pounds
The Ram Air Scoop weighs - 3.5 pounds

Let us know what else we can do for you!
Dave

 

+4 pounds. Not nearly as bad as I thought. Carbon fiber would cost too much (although I'm sure some would be willing to pay the price). Have you considered using some lighter material ie: fiberglass? Again, probably a production cost problem.

 

There is always the possibility that we can do something out of other materials like fibergalss, carbon fiber, plastics,etc., but it comes into a cost vs. benefit analysis. Can we make something lighter that will work as good, sure, will it cost more, sure, is loosing a couple pounds worth a couple hundred dollars, probably not in our book. The Groupe M intake is pretty similar in functionality to our intake and you can see what they are charging for that. Although a special edition carbon fiber version of ours, hmmm.......

 

Sure.... keep all the trick stuff for yourself

 

Don't worry if we make a carbon fiber version, we will gladly share them with the MINI community.

 

Ima need a carbon one for my Clubman Dave!

 

Tuls - You know we can take care of you on that!! Can't wait to see it

 

And you know all this-how? By CFD of the engine bay? If so, let's see the plots. By talking to the BMW engineers? Let's see the calculations that show how much radiator efficiency you MIGHT lose by opening up the scoop.

 

Thanks for your reply, it is obvious that you are an engineer and I think it would be very beneficial for people like yourself to ask questions like this of not only our products but also other manufacturers products also.

As to the answer to your straight forward question about how we "know all of this", lets look at what has happened to the hood scoop since the R56 was first introduced. When the car was first introduced, the hood scoop on the car was completely sealed with no openings. Later, we have been told for engine bay cooling, they opened the hood scoop slightly, but not all of the way.

So we set out testing our intake and some of the baseline tests we did tested the stock intake with the hood scoop blocked and it was no surprise that we measured the lowest engine bay pressures with the scoop blocked, but also the highest engine bay temperature. Once we switched to the current hood scoop design that BMW switched to, with some of the vents open on the hood scoop, we measured a decrease in underhood temperatures, but with an increase in engine bay pressures. Lastly when we removed the grill completely from the hood scoop we measured the highest engine bay pressures but the lowest engine bay temperatures, all of this testing done with the stock intake in place and no other variables changed.

Now going back to our textbooks on air flow there is the simple equation: V=CK(square root of P) where:

V= Velocity in feet per minute
C= Orifice coeficient
K= constant 4005 when measured in inchs of water (That constant is based on the assumption of an air density of [FONT=Arial, Helvetica, sans-serif][SIZE=-1] 0.075 lbs/ft)[/SIZE][/FONT]
P= Pressure differential across the orifice

Once we solve for V we can then plug it into the other formula Q=AV to solve for flow rate in cubic feet per minute where:

Q= flow rate in cubic feet per minute
A= Total orifice are expressed in cubic feet
V= Velocity in feet per minute

Looking at this equation it is pretty obvious that the flow rate for air through an orifice is going to be affected by the pressure differential. If we lower that pressure diffential we get less flow, if we raise the diffential we get more flow.

So I plugged in some of the numbers that we saw while testing and on these simple calculations we are looking at approx 6.5% decrease in cfm between the hood scoop partially blocked and hood scoop open all of the way.

Now we both know that there are many variables that would affect the outcomes of these calculations and this is just a quick explanation to show how a decrease in diffential pressure, decreases flow through any orifice, things like fin efficiency on the radiator and intercooler, internal efficiency of the radiator and intercooler, pressure differential between the intercooler and radiator and also between the radiator and the A/C condenser are just some factors. We would also want to gather a lot more pressure measurements behind the radiator and also infront of the vehicle to get a lot more accurate picture of the decrease we would see.

The statements that I made in my previous post is based on the pressure and temperature measurements that we made inside the engine bay while testing, and we know based on the equation above that a decrease in pressure differential equates to a decrease in flow through an orifice. It was a point that I thought people should consider when opening up the hood scoop on the car, as unlike you, some people blindly buy products without thinking about the consequences of the changes that they make to the system. The fact is there are also other things that will be affected with a higher engine bay pressure, front end lift will be affected and also undercar air flow will increase among other things. As you know a vehicle is a complicated system and to model every single change that would happen would take an amazing amount of time and computing power. Llike you said without doing a CFD on the entire vehicle with everyting modeled perfectly we would only be making a guess.

Is there a different reason that you can think of for BMW to originally send out the car with a closed hood scoop and then send the R56 out with a partially open hood scoop and not just open it up all of the way? As I stated in my earlier post, the fact remains that BMW will not just make a random change to a part for no reason, and they did make this change for a reason, as this change would have cost them time and money to do. These kind of changes are not something that manufacturers do unless they think it is needed. If BMW opened the hood scoop for underhood cooling, why do you think they didn't open the scoop completely? That will lower the engine bay temperature even more and if you are changing tooling anyway it is just as easy to do. Once again based on all of our measurements of pressure and temperature that we have done, the only reason we can see why BMW did not open the scoop all the way is because the increase in engine bay pressure only slightly decreased the engine bay temperature, however this would result in slightly less absolute cooling of the radiator, intercooler and A/C condenser. There may be another reason, and I would be happy to hear other theories that you may have.

Hopefully that didn't put everyone to sleep

 

just a thought based upon my physical observations......

I had a scoop that was partially opened from the factory, and I live in the rainy NorthWest. Before I removed the insert there was very little to no H20 getting into the engine bay. Now, after removing the insert, I do recieve some accumulation around the coils that sit on top the of engine. To me this probably wouldn't be seen as a good thing, and potentially hazardous, by the engineers at BMW....since they did take the time to apply a "warning high voltage" sticker there.

 

I am not sure if we will ever find out what the real reason was for MINI to change the hood scoop opening was, but you do bring up another valid reason.

Also wanted to post some pictures of a special version of the RIS that we did. We will be offering this full chrome version on the site, as it really turned out to be very nice looking installed on a dark car.







A little bit of bling

 

WOW!!

You have discovered a way to make a woman want to open the bonnet! a great big mirror =)

*ducks and hides*

 

 

Hey Dave,
I appreciate your explanation of pressure deltas calculated as above. Maybe I missed it, but what differences did you see in underhood pressure when comparing the RIS and your street setup?
Thanks.

 

Hi DDM guys

I received my intake yesterday and installed it this morning. Pretty good product.

First the things that weren’t great.
The intake box fits on the factory lower box fairly well, there is a significant gap on the right (passenger side) that could have been addressed with some rubber edging. The silicon elbow was a little long for the application but fit OK. One missing hose clamp and an extra piece of metal tubing.

DDM included both filters, K&N and UNI filter, I don’t know why but that solved the missing hose clamp issue, I used the K&N because the UNI filter kept slipping off the mounting tube when the hose clamp was tightened. This should have a flare or ridge at the end to keep the filter on.

On the positive side.
Some of the best packaging I have ever seen. Really, this was packed so darn good I can’t say it enough, some really good packing at DDM. The parts fit pretty darn good, not OEM good but still very nice. Nothing really special about something doing what it is supposed to do, but it does do it very well.

For other people installing this, the plastic retainers go through the tabs on the "V" shaped piece and then into the hood.

How does it work?
Cold air is good, hearing the turbo spool and hearing the blow-off airing out is pretty cool. There is a definite increase in low end torque and mid range highway acceleration (60-120mph legal) seems a little better. This is a good compliment to a cat-back exhaust, which went on last night. I saw a definite increase in low end power from the exhaust and that was increased by the DDM intake. RPM gains are definitly quicker. I would like to see the intake only difference over stock but I'm not pulling the exhaust to do it.

Having bought and used this intake I am confidant I made a good choice, I really wanted to make the scoop functional. Overall I’d give the DDM RIS a 95%.

Something to note, DDM punched their logo through the cover of the intake box where it is backed by the box, I put some aluminum tape behind the logo and it dresses the cover up nicely.

DDM packaging is top notch, really, I am impressed by the way they protect your investment. Pride of product shown through the shipping department, please DDM share this compliment with your people.