[335togo]

Greeting all, looking for one of these....please assist if you have one I'm in dire need! thx Jeff

https://burgertuning.com/products/up...intake-coupler

[drwillb]

I bought one when they first came out. Tried installing it but never fit quite right as it didn't seem to have the correct length of angle built in.

It's in a landfill somewhere, now.

BTW, I also ditched the BMS filter and went with a K&N drop in.

[wheela]

Hey, not sure if you're still looking, but this is finally back in stock at Burger Motorsports, just ordered one!

[Ozzie335i]

This piece is especially necessary if you have a port injection plate, which pulls the accordion apart, thus makes it easier for the thing to collapse in on itself. 24 psi here. The darn thing drove us crazy until a brother here at epost pointed the need for it, and where to get it.

[TheGoodTheBadTheUgly]

Originally Posted by Ozzie335i

This piece is especially necessary if you have a port injection plate, which pulls the accordion apart, thus makes it easier for the thing to collapse in on itself. 24 psi here. The darn thing drove us crazy until a brother here at epost pointed the need for it, and where to get it.

Nah I am not understanding this since the accordion is part of the air intake system which is at atmospherical pressure no? How could it be subjected to a high boost?

[wheela]

You're correct that it's not under boost, but the higher the boost, the greater the vacuum is present in the intake tract (atmospheric pressure at the inlet of the intake, but vacuum at the inlet to the turbo with a gradient between the two points). At high enough boost, the vacuum in the intake is great enough to pinch the accordion piece shut. They also see this happen with some of the turbo inlets on n54's.

[wheela]

At my power level, i'm guessing I won't notice a difference once I put this on. But for $25, I don't mind throwing it on in the hopes that a partially collapsing accordian coupler is partially choking off flow, and contributing to my horrendous boost fall off at higher rpm's.

[anjuna]

Originally Posted by wheela

You're correct that it's not under boost, but the higher the boost, the greater the vacuum is present in the intake tract (atmospheric pressure at the inlet of the intake, but vacuum at the inlet to the turbo with a gradient between the two points). At high enough boost, the vacuum in the intake is great enough to pinch the accordion piece shut. They also see this happen with some of the turbo inlets on n54's.

Nah, it's -0.2psi max (or for my friends who understand that negative psi cant exist, it's -0.0137 bar)

[TheGoodTheBadTheUgly]

I guess the applied vacuum makes a difference that is big enough to have the external pressure on the coupler dominate is noticeably bigger than the internal one. It's not a closed system so I can't see the vacuum alone, being big enough to collapse the accordion on itself, but having the vacuum create a lower pressure in the inlet and making the external pressure press on the inlet and coupler makes more sense in my head.

[wheela]

You're right, vacuum can't actually suck (don't get cute with that or pull, just like we don't actually suck a drink through a straw - it's the higher relative pressure that pushes towards the area of lower pressure. So it's not technically correct when I say the vacuum pinches it shut. It's like you said, the exterior pressure is higher than the interior pressure; the exterior pressure pushes it closed, since there's less pressure inside to balance the force from the outside.

Vacuum is realative, there's always atmospheric pressure at the entrance of the intake, but the pressure differential between atmospheric pressure at the intake inlet, and the lower pressure (vacuum) at the compressor inlet is what pushes the air into the turbo inlet. The more air your turbo is moving, the bigger the pressure differential between the intake and the compressor inlet has to be to push all that air to the turbo inlet. I've never measured the magnitude of this pressure differential, but many people, both n55 and people with silicone inlets on n54 struggle with inlets collapsing shut at high (25 ish psi?) boost levels. They resolve the issue with stiffer components that don't collapse under the pressure differential. On n54, they actually started making silicone inlets with metal coils in them (just like a stadard vacuum line) to prevent them from collapsing.

[Street of Rage]

What would be the inner diameter measurement if I buy a large silicone coupler on ebay? I wonder...

[Ozzie335i]

Originally Posted by Street of Rage

What would be the inner diameter measurement if I buy a large silicone coupler on ebay? I wonder...

Get the one from Burger, above, it's only 25 bucks, and form shaped to fit properly.

[wheela]

I just put mine on from Burger last weekend, it fit perfectly.

I wish I could say the same for the vrsf turbo inlet. It was a bear wrestling in, then once I got it in the turbo's hole, the bolt hole in the inlet didn't line up with the threaded hole in the block well enough to get the screw through. So I took the inlet back out to drill out that hole a bit and discovered a quarter of the first sealing o-ring had sheared off trying to get it in the turbo hole. So I just put the stock inlet back on, and the vrsf inlet is collecting dust. Not sure I want to get more o-rings and try again now that I realized I have no way of knowing if the o-rings will survive installation.