dirtyTurbo

I don't want to steal the spotlight or anything but my boost is set at 14 psi but always falls to 10, is this because of the waste gate or the turbo(both stock)?

I have another stock waste gate sitting on the shelf I may fab up some shims for...when I get bored

elargentino

This is your wategate.
There is a reason that noone has ever made a wastegate in this configuration - it was done to keep the 951 slower than the 930 - and it barely/arguably worked.
I have thrown so many of these out over the years, can't even count that high.

azmi951

A benefit of the Tial is lighter weight and dual port which allows you more precise boost control when combined with a quality boost controller.

If you do upgrade do not get rid of the factory bracket that supports the wastegate to the torque tube. If you do welds on the exhaust will crack given enough time....ask me how I know.

choinga

i dunno...made a big difference for me - currently still running the stock turbo.

TurboTommy

You blatantly put out a statement and don't know what you're talking about; that's what the real problem is on forums.
You put on a higher flowing turbo (hot and coldside), a Maf and exhaust, and all of a sudden you don't have the boost fall off any more. So then it's not the wastegate then, is it.
The wastegate is only partially responsible for lower than desired boost and if anything it affects spool-up time, not so much max power.
You should have sent all your probable good wastegates to me.

elargentino

Why would you assume I only used a larger turbo?
That is a strange response to my statement.
I have seen only one wastegate in my years of turbo car mechanics (I am old), and it was a 951, to the best of my reccollection.
I have used these wastegates with all kinds of turbochargers.
They open with backpressure, not control - because they are designed to be used with a very restrictive turbine/hotside combination that, in 5th gear, makes tremendous heat load.
Are you under the impression that a 951 safety valve wont open without control under the conditions you described? That is not true, believe me.

MooreBoost

lindsey racing uses the stock wastegate but modified to handle moore boost. why would one of the best racing companies for these cars use something that sucks if what you are saying is true?

i noticed that most of your posts state thatyou have a different opinion on everything...

choinga

For people that want something better than stock, but still meet PCA regulations?

MooreBoost

woudnt a modified stock wastegate and a aftermarket be classified under the same regulations?

elargentino

Choinga is , of course, correct.
Lindsey makes a good wastegate using the mandated OEM wastegate to abide PCA rules.
I am talking about their "clubgate" - we know where the word club comes from in the product - that would be the Porsche CLUB.

MooreBoost

fail on my part.

TurboTommy

????
I can't make out what the heck you're trying to say.

I don't know where my post implies I'm assuming anything about what YOU'RE doing with regards to turbchargers.

Opens without control??
There's a boost line running from the compressor discharge, through the cycling valve (or not), and to the wastegate diaphram.
So again: what are you saying, exactly?
As back pressure in the cross-over rises, it contributes to opening the gate, yes. (Lower the back pressure and boost goes up; I can't think of a healthier way of making power)

Oddjob

Clamp or disconnect the WG control line to the diaphragm and see how much boost pressure the motor/turbo will make. You will see over 20 psi on a stock K26. The stock WG does not push open much from back pressure in the crossover. Force from pressure acts normal/perpendicular to the surface, and the backside of the valve and stem has very little flat surface area for even high pressure to develop enough direct force to push the valve open.

Boost drop off after peak is primarily a function of the turbo efficiency/flow curves and the control system.

If you have the ability to custom map the KLR chip, you can run a lot of boost and a relatively flat boost curve (at moderate boost levels) with a stock turbo and a stock WG.

The dual ports are nice because they allow manual boost control, which is much easier and cheaper than aftermarket electronic boost controllers or trying to get a tuner to mess around with the KLR mapping (name one that does).

slap929

You need a dual port to use a manual boost controller? I bet Rogue_Ant has some clue or has done the KLR mapping you speak of.

Oddjob

You can use a manual controller on a single port WG, but because of the poor system response with either the pressure relief type or pressure regulator type, its near impossible to get a flat boost curve - you end up with the large mid range spike and high rpm drop off. Which is not a terrible thing. But for various reasons, many prefer the ability to hold the boost flat from midrange to high rpm.

I have not seen or heard of anyone in North America successfully custom mapping KLR chips to run higher boost using the factory CV. Aftermarket DME chips all require some external/mechanical modification to the boost system to increase boost (jetted banjo bolt, WG shims, drilled cycling valve, manual boost controller, aftermarket WG, etc).