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So I have the RPi intake scoops on. I also have the RPi Block off plates that close the bottom hole in the factory intake box..

Im wondering if the block off plates really make a difference.. I know by closing them off, it creates an even great vacuum inside the box.. Im just not sure if the ECU is happy with this setup.. When I have them in, it feels like a stronger grunt and perhaps a bit more torque, when i have them out, it feels like the car revs happier and perhaps there is more up top.. its really hard to tell if its worth it to keep them in or not..

Your guys thoughts?
 

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My opinion is go with the plates for slightly better dyno numbers...maybe
5hp/5tq?. On the dyno there seems to be a benefit. On the streets
it's too negligible to make any significant difference...that is until someone
proves otherwise.

I've been running with the plates for a while now. I had taken them out
and didn't really feel any difference but my dyno butt doesn't work very well.
They are in there right now but I don't really think about them.
 

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My beast feels "beastier" with them in. No apparent loss in low/mid but feel a slight gain in top end, hence beastier
 

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Hey Rambino, RPI has tested the Block Off Plates and they can give you an estimated 5-7 whp in the range of 4500-6800 rpm. I'm very confident with the RPI's engineering and I don't think that your ECU is unhappy with this set up. May be RPI can give you a more comprehensible explanation.

You have the sole right to inquire about this subject. Personally, I believe that a simple low-priced mode like the Block Off Plates that can be easily removed at anytime is quite an impressive mod to actually give you an approx. 5-7 whp gain.:applause:

My verdict is to keep them & forget about them unless you're really uncomfortable with them.
 

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looks like for the money the rpi setup is king

i am disappointed at the info provided by av8tir on the afe intake which looked so promising
 

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looks like for the money the rpi setup is king

i am disappointed at the info provided by av8tir on the afe intake which looked so promising
+1 :blink:
 

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Someone correct me if I'm wrong but do you make the same rwhp gain without the block-off plate.
I thought the gains are made with the plate.
Reason being, I use to have the ram air funnel behind the grills that came with the Gruppe M intake. I removed the intakes but kept the CF funnel which diverted more air supposedly to the boxes but it never showed any rwhp gains. It was a useless piece.
Now it's gone because of the ASR intakes.

Ranger
 

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Nope, Juan you make more with the plates. I have yet to try it though. But 5hp is 5hp...
 

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What does that air hole supply air to?

I tried searching and couldn't find the answer in a RPI Block-Off thread. But doesn't that hole supply air to the brakes?? I thought I had read that about a year ago when people started talking about the scoops.

My desire for additional cooling on the brakes of a 4,100 pound car trying to stop from 150mph would trump my need for 10 extra horsepower in a 500hp car. But that just applies to my needs and is not a shot at anyone here. And maybe I'm wrong about what that hole is for?:dunno:
 

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I have the block off plates as well. If you remove them, is there an issue with the screw holes that now exist in the factory airbox? Can they be left alone or do they need to be filled in. Always wondered about this.
 

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Someone correct me if I'm wrong but do you make the same rwhp gain without the block-off plate.
I thought the gains are made with the plate.
Reason being, I use to have the ram air funnel behind the grills that came with the Gruppe M intake. I removed the intakes but kept the CF funnel which diverted more air supposedly to the boxes but it never showed any rwhp gains. It was a useless piece.
Now it's gone because of the ASR intakes.

Ranger
I have seen the Gruppe M intake, it has similar concept, but ineffective. The 1" wide piece that run across the front grill to the Carbon Fiber airbox on each side was useless. It was designed to re-direct the air into the boxes. When the wind hit it, it created turbulance instead of re-directing air into the airbox due to its angle being flat parallel.

Back to the block-off plate, I think it will be useless without ram-air scoop. With the plate, the only way an air feed into the airbox was from the front through the scoop and it make it air-box seal since no air can be leak and out to the bottom through the brake duct which create more pressure inside the box. Initially, I thought at high speed, the airbox will be pressurized enough that block-off plate is not necessary, but I guess I was wrong. I'm going to get mine done ASAP
 

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I'm really not sure about the science behine the airbox pressurizing, however I know the scoops will feed potentially cooler air to the airfilters, resulting in lower IAT's and more power.

My theory was more or less proven by the M6 scoops and Dinan airfilters (another thread).

With the scoops, it should also pump more (and cooler) air to the front brakes if the plate is NOT blocked off. I also don't believe the plates to be worth much power-but again if the box sustains a pressure, it could work.

Either way, I believe the scoops to be a sound improvement to performance.
 

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I thought these plates blocked off the bottom of the airbox not the brake duct entrance?
 

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I thought these plates blocked off the bottom of the airbox not the brake duct entrance?
Yes, it's at bottom of the airbox, and sorry if my sentence misled anyone

it make it air-box seal since no air can be leak and out to the bottom through the brake duct which create more pressure inside the box
 

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I thought the bottom of the airbox was a route for air to get to the brakes? :dunno:

I guess I just need to get in there and look when I get home.
Tom, you are talking about the inlets on the bottom of the bumper. Where the block off plates are located is right under the air filter inside the actual airbox.

RPIers correct me if I'm wrong.
 

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I thought the bottom of the airbox was a route for air to get to the brakes? :dunno:
The connection between the brake duct and the airbox provides a secondary path INTO the air box. A similar "snorkel" was used on the European E36 M3, and was a common retrofit to US models.
 

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see the link attached inside the quote, the block-off plate go inside the airbox (part#16 on the last link) not the brake duct portion (part24 on the first link)

...The blockoff and intake tubing is interesting. Looking at
realoem I notice that the brake-duct -> airbox path is different
on an M5 vs M6:

For the M5 part 24 is the brake duct:
RealOEM.COM * BMW E60 M5 M FRONT BUMPER TRIM PANEL

For the M6 part 12 is the brake duct:
RealOEM.COM * BMW E63 M6 M FRONT BUMPER TRIM PANEL

The M6 clearly shows the path to the bottom of the air box (part 16):

RealOEM.COM * BMW E60 M5 INTAKE MUFFLER/FILTER CARTRIDGE/HFM

While the M5 doesn't. I assume the M5 must have this as well. But it
does seem that the construction is a little different. The airbox for
both cars are the same though. Perhaps the different setups explain
the different dyno numbers? Maybe there is more to gain for the
M5 vs the M6?
 

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The connection between the brake duct and the airbox provides a secondary path INTO the air box. A similar "snorkel" was used on the European E36 M3, and was a common retrofit to US models.

This is correct. A tuft test (putting small pieces of yarn in the duct and seeing which way they blow) shows the air flows up into the airbox through this duct, so the blockoff will not affect brake cooling.
 
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