At what boost levels does the stock Vortech bypass valve become overwhelmed. I'm planning on starting with 14 psi and possibly going to end up at 16 psi. Will the bypass valve that comes with the T-Trim kit work?

 

the stock Bosch bypass valve is good for 10 PSI...I dont believe this due to alot of people saying that they wont even hold 6 at times. I decided to go all out and got the Vortec Race version bypass valve from vortec It was somewhere in the neighborhood of 300 with valve, flange, gasket and shipping

Hope this helps
Matt

 

My stock bypass valve was working fine with a 7" crank pulley and a 2.95 blower pulley. I was seeing approx 14 psi. Motor had plenty of vaccum cruising on the hywy at 3500rpm (no overdrive)

 

The problem with the stock bypass isn't pressure its volume. It only has a 3/4 inlet outlet, when you pulley up you move more air then its meant to deal with and when you shift at WOT the air has no place to go and you will damage the imput bearing.
How do I know ? a 7.2/2.95 pulley combo a 11.0 131.25 timeslip and a damaged vortec SQ V2 head unit, at least vortec replaced bearings under warranty because the LT1 has a auto tensioner if it had a manual tensioner they would not have repaired it.

John

 

No disrespect, but it seems like belt tension would play a bigger role in input bearing problems than the air volume and pressure that wasnt being bypassed by the stock valve. How do you know your damage was caused by the stock bypass?

How many other people have had input shaft problems due to the stock bypass valve? My s-trim has over 30k miles with the stock bypass.

 

I'm hoping the stock one will work for now, I have an A4 so there won't be any sudden throttle closing for shifting, might happen on deceleration though. Is it possible to use 2 of the bosch style bypass valves to achieve the necessary flow? Another stock type bypass valve is only 120.00 compared to 230.00 for the race bypass valve and 300.00 for the mondo.What options do I have? If I had to I could probably scrape together enough for the mondo BP valve, but I'm building a complete blower motor right now and I'm just a broke *** firefighter. I am going to get the mondo BP, but it would be nice if the stock one would work without damaging anything for a coulpe of months.

 

The stock bypass valve is a Bosch part that you can by for $30.

 

Stock Bosch bypass valve that came with my Vortech S Trim kit, P/N 0 280 142 102. Upgrade Bosch part 0 280 142 110 (same size just better internal construction to extend diaphram life).

 

Cool, I was looking at the prices on proficientperformance.com. Where do you get them for that price, directly from Bosch? Would 2 of these take care of the bypass duties or does it not work that way? Does anybody know about this?

 

the "110" valve is also known as a 710N, see this link:

http://www.ecstuning.com/stage/edpd/...ategory=Intake

Two should work in parallel.

 

The belt tensioner is automatic so you can't overtighten belt, what does happen is when you release the throttle at high rpm between shifts and the air has no place to go the belt starts to slip and the chatter kills the bearings. Turbos also fail for the same reson if you don't have a blowoff or bypass.
If a supercharger does live with the small bypass is only because your not moving enough air to need a larger bypass.
Also I spoke to a engineer at vortec after my bearing problem and he actually told me the same thing, change my bypass which I did.

John

 

i'm only running 8psi but i'm running a BOV from a eclipse.

 

John - A short belt can cause more belt tension - not saying that's your case, just that it's possible...