It seems to me that if the wastegate sees manifold pressure, then when the throttle is slammed shut, the wastegate will also slam shut, which will cause the turbo to go way up in rpm, which will require less of a restriction to throw it past the surge limit. Basically if the wastegate goes shut, the turbo will make more pressure, and combined the throttle being shut, without a bov there will be problems (well more problems than with the wg referenced to the tube before the TB). Any problems with the wg seeing tube before TB?

 

BTW right now my WG is referenced to the manifold and there is considerable surge.

 

you can hook it up anywhere evan right off the turbo compressor housing. i run it off the manifold that way it monitors after the pressure drop that occurs through the intercooler. but you can hook it up where ever.

Rob

 

I think you are ignoring the problem. I know you can run it off the compressor housing, but I am just not sure about the intake manifold past the TB. Like I said above, I believe it would cause problems.

 

What I think should be done is hook the wastegate in before the the throttle body. Thats where the pressure is gonna be before and after the throttlebody is closed and probably the most acurate. Thats how stock internal wastegates work as well.

 

ive seen alot of people hooking up the vac source off the compressor housing and alot hooking it off of the brake booster. there has been several arguments about one another.

what i want to know is, why dont they just get a T splitter and hook the wastegate up to both sources, the compressor housing and brake booster?

 

hook up the waste gate to the compressor, buy a bov and a profec-b and you are set

 

I've had both an internal waste gate and my new tial wg both hooked to the charge pipe before the tb and never had any problems

 

[Modified by spooled b16, 8:01 PM 12/18/2002]

 

Why would I hook up the wastegate to the compressor? I want to read boost after the pressure drop, right? If I want my engine to see 6.5 lbs, and I have an intercooler, then running the wastegate off of the compressor would result in my engine only seeing about 5.5 lbs due to pressure loss. If it's hooked up before the TB, then the wastegate will only open if my engine is actually seeing the full amount.

 

exactly

 

i agree

 

Heres why your wrong. If you dont have a boost controler, its gonna regulate on the spring anyways giving you the correct amount of boost. If you have a boost controler, your just going to adjust the controler to what the boost gauge reads anyways which will be off a boost gauge operated from the manifold. My HKS EVC has to see vacum/boost before the tb and after to work.

 

[Modified by ImAcracker, 3:00 AM 12/21/2002]

 

Because this would cause a vacum leak.

 

Mike, are you saying that it doesnt matter where you hook up the wastegate

 

It does matter...just depends on how your controling boost. If your just running it off the wastegate spring...thats really whats controling it, not the vacum line. Every setup is gonna be different.

 

If you're not running a boost controller then the wastegate will open at the preset amount of boost (spring) seen by the vacuum line. Hooking it up at the compressor will make it open at 6psi (example) at the compressor. You may have a little pressure drop across the ic so the motor would only see 5psi (example). If you have it going to the manifold, it will open at 6psi in the manifold. With a boost controller, it really doesn't matter since you have control over it.

 

" It does matter...just depends on how your controling boost. If your just running it off the wastegate spring...thats really whats controling it, not the vacum line. Every setup is gonna be different. "

What? The spring doesn't do much... the WG is referenced on both sides - one side to atmosphere, and one side to compressor outlet or wherever you want to reference boost from. This might be what you are calling the vacuum line, but it also sees boost, and it doesn't even ever have to see boost. I'm not sure if you fully understood my problem/question.

 

Just hook the vac line between the I/C and the TB. You'll never see a problem like you're describing again,ok?

Sometimes the way people word things don't make sense to someone in a different area, and it causes turmoil between the two parties. Which in turn creates flaming. I think we're all saying the same thing, but in different ways. He just needs to run the vac line between the I/C and the TB to eliminate his surge problem with-out a boost controller. A boost controller would be a wise purchase though.