Megatron-UK

Hi guys, I've currently got the car up on the ramp and have all of the exhaust system soaking with release oil in prep for total replacement before the yearly MOT test... but I wanted to ask if anyone had fitted a simple mechanical boost controller instead of a fixed spring or electronic controller?

I fancy the idea of dialling the boost up a little (with a new gauge and fuelling to suit), but don't like the idea of fitting a fixed spring in the wastegate. How would a simple ball + spring type controller be fitted with the setup we've got in the 964 Turbo? I've used them in the past with 'standard' turbos that have integral wastegate actuators (fit between the vacuum hose between the turbo housing and the actuator), but the 911 setup is very different, is it not?

Metal Guru

I installed a Joe P mechanical boost controller that could control two wastegates when I installed my M&K exhaust.
I didn't want to end up buying a lot of springs and constantly be changing them since I didn't know where the boost would end up being with the new exhaust.
I've pretty much set mine up to .85 bar and left it there but I suppose you could do the dial-a-death thing with one.
The nice feature to a ball and spring controller like the Joe P one is that it holds the wastegates completely shut until the desired pressure is achieved, or so it is claimed.

turboholic

I ran a ball and spring type BC before I switched to electronic boost control. Worked fine. It connects into the line leading from the IC to bottom of WG. No earlier spool up though, at least not noticeable. Only difference between manual and electronic is that with the electronic unit I can control the boost from the cockpit while driving. MBCs are cheap and work good

Megatron-UK

Thanks for the info guys, I wondered were it was going to fit!
Sounds like a simple job (other than adjusting it until the right level is found) - I was thinking of an overall boost of .85-0.9bar; the 1bar springs I've seen for the stock wastegate will probably be too much when combined with my existing decat and new headers.

turboholic

with a 0,7bar spring, decat and headers you will probably already achieve ~0,9bar of boost. This was the case with my car. I added a boost controller for additional 0,1bar to get a solid 1bar of boost. With a 1bar spring, decat and headers you will see more then 1bar of boost and wont be able to dial the boost back until you disassemble the WG.

Megatron-UK

Yep, that's the reasoning behind not going for a spring rated at 1bar - I thought it would be just too much; with the mechanical adjuster you can always dial all of the adjustment out and be left with the stock wastegate setting.

JBL930

It's defo the way forward, just never adjust abover 1.0bar, and check on a dyno that your fuel is ok. I never understand why anyone would fit a new spring when this way is so easy, more controllable, reversed in minutes, and arguably helps to build boost a little quicker, a complete no brainer it seams