Ram air scoop fitted

Who gained 10bhp? I certainly wouldn't expect that.

I suppose you gained bhp by getting a personalised plate? That's all this is for me, a cosmetic product.
 
10bhp is what RPI claim so that gives you an idea of their credibility. I wonder how much computational fluid dynamics went into the design compared to BMW.

I don't have a personalised plate, it's semi blanked out for cloning reasons.

Seems odd to buy a performance modification for cosmetic reasons when you hardly see it and it's not exactly a thing of beauty but maybe that's just me.
 
Steve84N said:
There's nothing wrong with the size of the standard opening, at no point does my engine feel breathless. In fact it feels like it wants to rev beyond 6,600rpm.

If BMW could get more power simply by increasing the size of the opening they would have done it. Think of a vacuum cleaner with a normal large attachment on the end of the hose compared to the crevice tool with the small nozzle. It still flows the same amount of air but the smaller nozzle has more powerful suction because to get the same volume through in the same amount of time the air must travel faster. So in actual fact a smaller opening will accelerate the air into the intake more than a larger one. Another example is a supersonic jet engine which has a convergent to divergent airflow. By having a large space for air to enter (area behind grill), a small aperture (air intake opening) and a larger space behind it (airbox) you create two low pressure areas that accelerates the air through the smaller opening. Jet engines cannot go supersonic without this concept as simple convergent nozzles do not work. Go figure...

These forces are far greater than what is in essence putting your hand out of the window and creating a dirty airstream. The scoop is directing air towards the wing where it will deflect back and create turbulent vortices. It's not taking an opening on the surface of the car and funnelling that directly enclosed into the intake.

Consider what happens when a pressurised plane breaches it's hull, the air is very quickly sucked out the small opening without someone having to deflect the airflow with a poxy scoop...
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This is very interesting, thanks for the information.
 
Steve84N said:
There's nothing wrong with the size of the standard opening, at no point does my engine feel breathless. In fact it feels like it wants to rev beyond 6,600rpm.

If BMW could get more power simply by increasing the size of the opening they would have done it. Think of a vacuum cleaner with a normal large attachment on the end of the hose compared to the crevice tool with the small nozzle. It still flows the same amount of air but the smaller nozzle has more powerful suction because to get the same volume through in the same amount of time the air must travel faster. So in actual fact a smaller opening will accelerate the air into the intake more than a larger one. Another example is a supersonic jet engine which has a convergent to divergent airflow. By having a large space for air to enter (area behind grill), a small aperture (air intake opening) and a larger space behind it (airbox) you create two low pressure areas that accelerates the air through the smaller opening. Jet engines cannot go supersonic without this concept as simple convergent nozzles do not work. Go figure...

These forces are far greater than what is in essence putting your hand out of the window and creating a dirty airstream. The scoop is directing air towards the wing where it will deflect back and create turbulent vortices. It's not taking an opening on the surface of the car and funnelling that directly enclosed into the intake.

Consider what happens when a pressurised plane breaches it's hull, the air is very quickly sucked out the small opening without someone having to deflect the airflow with a poxy scoop...
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Ram Air Scoop for Sale. LOL
 
Ant said:
Steve84N said:
I don't have a personalised plate, it's semi blanked out for cloning reasons.
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lol alright Jack Bauer way to stay off the grid
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Mock all you like but I've seen it on a number of occasions through various forums. If you're a criminal why go hunting for a car to clone when you can easily browse all the colours etc on forums.
 
Personally, I find that there is a slight raspier noise when under hard acceleration. It may not be +10bhp, but frankly I don't care - that wasn't what I bought one for. its a nice piece of kit, and very well made by Dan.
 
performance increase or not, once painted red it will look better than my current broken OEM scoop so its going on anyway, its good to see peoples opinions/advice/concerns but on this instance i will respectably ignore them :)
 
Did some little mods to mine too. Still to fit though. Probably incur the wrath of the M Police as well..... :D
Cheers Dan. I like mine. There will always be some party poopers around... :poke:
 
jakblade said:
Did some little mods to mine too. Still to fit though. Probably incur the wrath of the M Police as well..... :D
Cheers Dan. I like mine. There will always be some party poopers around... :poke:
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Cool 8) :thumbsup:
 
jakblade said:
Did some little mods to mine too. Still to fit though. Probably incur the wrath of the M Police as well..... :D
Cheers Dan. I like mine. There will always be some party poopers around... :poke:
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Looks great, are they decals or paint? :thumbsup:

Talking of party poopers, I have fang protectors (also useless)spare so advertised on the German z4 forum. The second comment on the thread said "they weren't suitable for use on German roads" and that "if fitted they would be a hazard for animals and humans"!
 
dans6490 said:
jakblade said:
Did some little mods to mine too. Still to fit though. Probably incur the wrath of the M Police as well..... :D
Cheers Dan. I like mine. There will always be some party poopers around... :poke:
Click to expand...

Looks great, are they decals or paint? :thumbsup:

Talking of party poopers, I have fang protectors (also useless)spare so advertised on the German z4 forum. The second comment on the thread said "they weren't suitable for use on German roads" and that "if fitted they would be a hazard for animals and humans"!
Click to expand...

Cheers Dan. The stripes are vinyl I cut from sheets I got from eBay. Bleedin expensive too... £2.97 for 3 A4 sheets. :rofl: bmw was vinyl cut decal from eBay too. Can post you some strips if you interested.
German TUV approval will be what's stopping the fang tectors. Think I'm going to take my "flipper" fang tectors off. I keep catching 'em. Do have any of your stainless ones left?

And cheers Marlon. :thumbsup:
 
cossie si said:
Took off kidney grill. Removed the original plastic air scoop. It's held in place with a plastic rivet. Used a pair of pliers to pull out centre pin and rivet, then pull out original scoop! Offered new scoop up! Marked top hole first! Pretty much the furthest point up on the trim in the top corner. Used small drill bit to pilot hole. You can just get it in at angle, which is ideal for getting a long Phillips in at the same angle (easier than using a stubby). Fitted the top screw, then marked up the second hole. Remove scoop, same as above for bottom hole. Re fitted scoop with both screws, bent bottom leg in to meet side plastic trim, marked up hole, removed scoop again then repeated the above. You will have to open up the holes for the supplied screws to fit or use smaller screws. I opened them up slightly as smaller screws may not be enough to support it. The fit is very good, as i said easily as good as any other aftermarket product I've fitted. Scoop is very hefty, but not heavy, and the three screws are more than enough to support it. I was surprised how rigid it was when done.
Before last fit i gave the rear of the scoop and the screw holes a blast of black Waxoil then the heads of the screws when fitted. will get out later in the week to see if i can see any difference.
15-20 minute job max with the right tools. One thing i did do was rubbed a magnet across my screwdriver to make fitting the screw on the bottom leg a lot easier!
Very impressed Dan! Great job mate! Thanks for all your effort :)
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Thanks for this. Indeed a 20 min job.....once you've gone to b&q to get the right screwdriver....after an hour dicking around with normal one and drill heads that are worn out....one day I'll learn. And no need to drill guide holes btw
 
dans6490 said:
jakblade said:
Did some little mods to mine too. Still to fit though. Probably incur the wrath of the M Police as well..... :D
Cheers Dan. I like mine. There will always be some party poopers around... :poke:
Click to expand...

Looks great, are they decals or paint? :thumbsup:

Talking of party poopers, I have fang protectors (also useless)spare so advertised on the German z4 forum. The second comment on the thread said "they weren't suitable for use on German roads" and that "if fitted they would be a hazard for animals and humans"!
Click to expand...

I wonder if they were referring to TUV which does sound a little strict! For example, the chap who recently bought the modified Alpina has had to take all sorts of bits off in order to get it to pass as 'fit for German roads'.

Still, surely it's just a case of remove, test, replace!
 
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