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Vr6 BMC CDA Restrictive?

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I have spoken to a few vw tuners that have suggested that the bmc is s**t and I should put a normal cone filter on and make a heat shield around it like the jabba sport one that fits the g60?

 

they said its soo restrictive they removed it of a r32 and gained 5bhp side by side with the open cone and heat shield?

 

if anyone can shine a light on it as all the vr6 forums say bmc is one of the best?

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My old VR gained 7 bhp from the bmc! Who actually said this? An open cone in the VR bay would have to have an amazing heat shield to stop heatsoak. The best fitting heat shield you can get is already fitted to the bmc :lol: An open cone routed through the carbon can hole is a different proposition though...

 

I'd go bmc, carbonio or standard air box if it was me.

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The BMC being carbon keeps the air cooler when under bonnet temps are high. That much gain from any filter is a myth tbh. The BMC creates an incredible noise, and the inlet side of the filter is far bigger and less restrictive than a standard airbox. Put a cold air feed onto the BMC and your on to a winner in all departments.

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And some flood water :p

 

Yeah.... if you drive it through a flood, Which is not on my bucket list.

 

Never had any issue whatsoever in harsh rain

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Yeah.... if you drive it through a flood, Which is not on my bucket list.

 

Never had any issue whatsoever in harsh rain

 

Hehe was always put off them because of deep water low car problem but they do sound nice on full chat

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I stand corrected if cazza has figures to back up the gains. :confused:

 

It was dyno'd at Stealth before and after, although there was a few months between runs.

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BMC is spot on but there are two sizes and some numptys by the smaller one. Same diameter but shorter length and so smaller cone. The full size one is good for anything an NA tuned VR6 might need.

 

Consider though that a tuned R32 is almost 50% more power and due to te design of the head, flows more up top.

So for a 12v vr6 it is fine, but maybe no for an R32.

 

Also, the BMC needs a cold air feed to the intake end. It's supposed to shield the intake air from engine bay temps. But you see some folks running a BMC open to the bay at the intake end.....pointless!

 

I found that the open cone made the car run rough at idle. BMC idles solid and pick up from a stand still is better, cold air!

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I had a better run at stealth with std airbox when getting mine mapped. Was a marginal difference mind you. The noise is nice though!

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Hehe was always put off them because of deep water low car problem but they do sound nice on full chat

 

Still addictive to this day Jon! I see what you mean but we would be talking 40mm deep water before it would reach the cone. Maybe not so suitable for a daily especially as I love a good puddle in the company car!

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I don't think any of them give much in the way of power gains, but the BMC is less likely to lose power which some of the exposed cones will. It's the best way to get the noise without heat soak.

 

If you wanted to be creative run a pipe from the intake down into the bumper and maybe lose the fog lights for a vent. If you wanted a serious solution I would make a pipe out of fibreglass (or be lucky with some Pre cut hoses) rather than ribbed flexi pipe for a nice smooth airflow and minimal heat soak.

 

My 135i has no front fogs like the smaller engined cars have, it has vents to cool the brakes there instead.

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a bloke niki from R tech he told me to get rid off it and do something like https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash4/998605_10152968110880157_596697936_n.jpg

 

I thought it was R Tech who said that. They've told a lot of people that and it's unsubstantiated nonsense.

 

I suspect the R32 in question had the universal CDA85-150 fitted, which is what most, if not all, VR6s use. BMC do an R32 specific one, which is larger.

 

As Cazza said, he and Stealth have found a 7hp gain on a VR6. Stealth also saw a 14hp gain on an R32.

 

I used a BMC CDA on my VR6 turbo and it made 392hp with 11psi of boost. Restrictive? I don't think so :D With an open cone it made less power and just felt flat off boost, made a heck of a lot more noise and got dirtier far, far quicker.

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Plus most people seem to hang the cone filter directly off the MAF without supporting it, which cracks the inlet elbow and gives the MAF wires metal fatigue. Ask me how I know... ;)

 

Stone

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In the case of R Tech finding more power after taking the BMC off, how do we know the owner of the car had recently cleaned and over oiled it, thereby screwing up the MAF readings? Seems likely to me because I have never seen a stock airbox make more power than a BMC on a VR6 or R32.

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I've got an 24v specific BMC in the shed waiting to fit, it's even got a screw type fitment just like the standard airbox. I really need to get it sorted as the 24v just sucks in warm air with an open cone filter.... but what have people used for a cold air feed? I'm thinking a piece of samco type hose and a collector located near/behind a healight?

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DIdnt notice any power difference on mine but the BMC certainly sharpened the throttle response and pick up... then there's the noise!!!!!!!

 

That's what you notice the most, improved throttle response. If you have ~ 200hp to begin with, you won't FEEL another 5-10hp tbh.

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