Blow Off Valve Help, Please

piperporsche180 · piperporsche180's Garage

I decided to go out and buy a nice blow off valve to replace my stock one.

It is very nice but Im not sure how to mount it. Im planning on keeping the stock air density unit as well as the stock air box.

The BOV pipe and the hard pipe are nearly the same size, 2" for the hard pipe and 2 1/8" for the bov pipe.

Should I get a pipe made like the one below, but have the BOV on the opposite side?

I got the picture from the link below:

SFR Hard Pipes / Godzilla Blow-off Valve

Thanks guys.

Techno Duck · Techno Duck's Garage

Is that a Greddy clone or an actual Type RS, never seen it with the gold body before.

Anyhow you need to get the correct matching flange, then weld that to your IC pipes. I am sure if you contact Tim at SFR he can do it for you. You can get a different sized inlet, it does not have to be the same 40mm that came with the valve. Also you should recirculate the valve as it was done from the factory, the discharge fitting on the valve now is setup for dump to atmosphere. You need to get the 19mm recirc fitting to mate up with the stock j-boot.

Your probably going to have to mount it the same way as that Turbnonetics Godzilla valve because there is very little space on the other side being crammed up against the expansion tank.

My take on this, its going to be alot of work to get it to fit especially if you want to retain the stock airbox and airflow meter. There is just zero space with all that stuff still in place. Typically you would want to go with routing similar to what was pictured (essentially going with a MAF) to have enough space to plumb that bypass valve in. With the stock airbox and airflow meter, that is basically taking up all the space on that side of the IC pipe. Personally, i would go with the usual Evo Motorsport or Forge piston type bypass valve. They are direct replacements for the stock Bosch valve and require no modifications to work.

A buddy of mine has the older version of that valve, the Type S (purple top). Its a very distinct sound from it due to it being a diaphragm type rather than the typical piston type most people upgrade too. I have been thinking about getting one to put on my car but they are all second hand (Greddy lost rights to manufacture it apparently, the Type RS is the replacement and not as good i hear). They also need rebuilds due to the diaphragm tearing..which is like $80 to replace!

wild man · 01-05-2010, 05:50 AM

I agree with TD that you should have gotten one that is direct fit for what you have (stock setup). Basically, you purchased the wrong one. You got a blow-off valve, when you should have gotten a by-pass valve.

piperporsche180 · piperporsche180's Garage

My friend John and I bought one of these each, they were only $30 brand new from a guy on ebay. His ebay listing ended the 31st of Dec. Ill tell you if he reposts them.

Thanks a ton guys for your quick responses!

choinga · 01-05-2010, 04:41 PM

This is all you need...high quality and a stock fit:

http://www.lindseyracing.com/LR/Porsche//99-0609-100.html

p-talk · p-talk's Garage

Or an 034 Motorsports one - billet aluminum, polished silver or black, stock fit, and cheaper:

Bypass Valve, 034 Spec - 034 MOTORSPORT

Quote:

Originally Posted by choinga

This is all you need...high quality and a stock fit:

BYPASS VALVE BILLET REPLACEMENT NON-DIAPHRAGM at LINDSEY RACING - Your Porsche Performance Parts Center

alxdgr8 · 01-06-2010, 02:27 PM

Throw that greddy knockoff in the trash! They are junk! Spend the money and get a good recirculating valve (034, Forge, Bailey). They can be bought for $50-75 used. If are you going to use a Greddy, get a real Type S and recirculate it. There is a 3000GT VR4 parts manufact. that makes a flange that bolts to the bottom with a "nipple" that allows you to mount it in the same position as the stock Bosch valve. You can even use the stock hoses.