arlockstedt

I'm running around 12-15 lbs boost on the vortech setup and was wondering if i need to replace the bypass valve that came stock with the kit. I don't think the valve is staying closed under boost.....and causing me to only see around 10-11lbs. I know it can and will do more because it did when i got the car back with the motor rebuild in it. Any clues or suggestions?

I have seen people change them to the "HKS Bypass valve." are these better than stock?

JoBy

I don't know what the Vortech valve looks like.

It should have a vaccum/boost reference port connected to the plenum.

During WOT both sides of the valve see the same pressure and the spring forces it closed, regardless of boost pressure.

With the throttle closed it is the engine vaccum that opens the valve.

arlockstedt

so than whats the point of the race valves?

JoBy

If you need to dump more air faster you need a bigger valve. Att types SHOULD be closed during WOT unless they are faulty or a very bad design.

I think the most common reson for people changing them are the fast and furious bling factor.

But as I said, I don't know anything about the vortech bypass valve.

arlockstedt

anyone running a vortech setup with a different than stock bypass valve? if so why did u upgrade?

RVY

I did it to blow off some boost in 1st gear and keep some rubber on the tires.

AKS Racing

Not Vortech, but the principal is the same.

I run a different set-up (twin Vortech Mondo Race valves), to allow the SC ducting to stay together and to keep from "hanging the MB throttle" between gear changes. 2300CFM will blow connectors apart regularly and will allow you to keep accelerating when you really don't want to.
Aaron

arlockstedt

ok so if its not the bypass valve not closing...what are some possibilities for the boost decrease? I do note some belt slipage. also would there be a gain from a 48 to 58mm tb or a larger mass air flow sensor with a supercharged setup? thanks for any input

JoBy

You van temporarily block off the bypass valve to verify if that is the problem or not.

Belt slipage is a common problem.

You can have another leak somewhere.

Clogged air filter?


You would probably not notice any gain from a larger TB or MAF. With boost they flow a lot more air.

LPDesRoche

If you are still running the cheap plastic bosch bypass valve that comes stock with your kit this may indeed be your problem. I have seen them start bleeding boost above 10#. It's just not what they were really intended for. If you do infact have one of the better Vortech (aluminum bodied valves) it's probably something else unless yours just happens to be faulty.