Peter Carroll/Toronto

Years ago I replaced all that stuff with a computer. Way better...

ossie308

Resurrecting this thread as I am dealing with a similar issue. Does anyone have a simple diagram showing what the wastegate plumbing should like on an original 930? It wasn't clear to me on the previous diagrams on this thread if any of them were showing the original setup/components?

mel_t_vin

The diagram Peter uploaded in post 13 is close to the OE set up.

On the diagram, follow the "6mm supply line" from the IM plenum [from the intercooler on the OE system] toward the waste gate. If you remove the small control line going to, and leaving, the "manual air regulator", and remove the regulator, the diagram would be representative of the OE system.

Note: intercooler not shown in diagram.

ossie308

Many thanks. Are there's two lines going to the Intercooler, one underneath and one on the AC side, correct?

mel_t_vin

There are three ports on the intercooler...one on the left side and two on the right side.

The one on the left provides a pressure signal to the waste gate. One on the right is capped off, and the other goes to the AAR.

ossie308

Thanks, that was helpful. If anyone has a photo of the top of a stock 930 engine with the Intercooler removed then that would also help me a lot. there's a few on the web but hard to tell what is stock and what is not.

The previous owner made so many "mods" and added lots of pretty red and yellow tubing (some which goes nowhere!) that it's difficult for me to tell if I have any components replaced or missing.

mel_t_vin

You would probably get better results by posting center-left, on-center, and center-right photos of your motor here, and let folks peruse over its current configuration.

ossie308

Sure, here's some photos I have on me at the moment, can send more later. Turbo is a K27, boost controller is (or more correctly was) a AEM Tru Boost. Please excuse the bling, this was the previous owners creation not mine!

mel_t_vin

You didn't really say what your intent was. Go back to 100% stock? Inventory what is/is not factory?

K27...not stock. OE was a KKK 3LDZ.

AEM...not stock [I would toss that in the waste bin]. OE boost controller was simply a spring in the waste gate. How much boost is your motor running...15 lbs?

From the photos, you still have the factory: 1) compressor bypass valve assembly [large cast aluminum housing] between the fan shroud and air box, 2) vacuum limiter [60mm circular part with attached red vac hose between shroud and CBV housing], 3) boost pressure sender [to right of vacuum limiter attached to CBV housing], 4) aux air regulator [to right of CBV housing with attached blue vac hose], 5) ignition coil, 6) turbo compressor discharge up pipe [to left of distributer cap], 7) intercooler, and 8) waste gate.

If you don't like the red/blue vac hose, you can still find black, cloth-braided, hose to un-bling the engine compartment.

ossie308

Actually I did say earlier that I am taking the car back to stock. I realise the KKK isn't stock but I can live with that given it reduces the lag.

Yes already done that with glee, never trust those buggers, Motronic is the only way to do that properly from my past experiences (968 Turbo RS) but not intending to go down that path with this.

Don't know at this point as not hooked up the test gauge. Stock boost gauge on the dash goes beyond 1 bar and you can make it hit the cut out when pushed hard in 1st.

Thanks very helpful, so can I assume from this there isn't any obvious component missing from what you can see?

It's more the yellow fan I was referring too!! Thanks for your help

mel_t_vin

This would worry me...a bit.

More boost [>15 psi] + stock intercooler + stock headers ---> lean AFR and/or detonation. Have you removed all manual boost control? So, the waste gate spring is the only mechanism controlling boost pressure?

Until you get this car on a dyno to verify AFR throughout the rev range at full boost, I would be very careful with the go pedal.

The rest of the engine compartment looks mostly stock, save for the colorful vacuum lines and what appears to be the boost controller piping.

ossie308

Yes have removed manual boost control and blocked both lines that were going to it. Plan to take it to a local Porsche specialist to will heed your advice in the meantime, thanks!

mel_t_vin

You've taken the manual boost controller out of the equation...and the boost gauge still climbs past 1 bar?

Is the vacuum hose from the left side of the intercooler connected to the side port of the waste gate? If not, that could be the problem. If so, then someone has either replaced the OE waste gate spring with a stiffer one [e.g. 1.0 bar or 1.2 bar] or shimmed it to increase its resistance.