maglev_disaster

Hello!

I remember reading somewhere that the early 3 liter 930s had a manual boost control **** located inside the cabin. I can't seem to find any evidence to support this and have tried searching all over the internet for things like "930 manual boost control", "911 turbo boost ****" and for the owner's manuals for the early 930s, all with no luck.

Could someone confirm that these boost ***** did exist and how they function?

Thanks!

Arnie1

The manual boost controller was not a part or option on a 930. It was an aftermarket dial used to increase the boost manually over stock. I have seen the dial placed under the dashboard or in the engine compartment. When I bought my used 89 930 the previous owner had installed the yellow dial in the engine compartment. The manual boost controller is very dangerous and turning the dial too much will cause over boost and destroy your engine. It is called the dial of death.

I immediately had it removed and installed an electronic boost controller where you can set a max safe boost limit.

Maltese Falcon

Yes these boost ***** did exist as factory equipment, but only on the 934, 935 turbos
Marty

mel_t_vin

Safe boost limit...explain that to my friend and his grenaded 2.8L. When his [GReddy] EBC failed, his modified K27 spooled to 2.2 bar before intake pressures were "vented" through the bottom of his block.

Personally, I would never run a remote boost controller, MBC or EBC, on my 3.3L. Track car, sure...but the original motor in my street car is much, much, too valuable.

IMO, anything besides a waste gate spring is fraught with danger. And while waste gates can, and do, fail, most of those failure modes result in little or no boost.

YMMV...

Arnie1

I disagree there are many reasons why your friend's engine blew up. What was the controller set at in your friend's car? First of all 2.8 will definitely do that. Are sure it was not the Waste gate that malfunctioned which did not open causing the over boost issue? This is a common waste gate failure. My electronic controller is set to 1 bar and has a fail safe for protection. I have had it in my car for 8 years and never a problem. But I always keep my eye on the turbo boost gauge just in case. 1 bar is the recommended safe boost to use if you do not go with the stock controller which is set for 0.8 bar. You could use a 1 bar spring but they are not very accurate. You should also use common sense watch the turbo boost gauge if you pin the needle just let up on the gas.

mel_t_vin

There is one, and only one, reason my friend's 2.8L grenaded...his GReddy EBC, set to 0.9 bar, failed.

Huh? Most motors will grenade when the [pos] EBC fails and subjects the internals to 2+ bar of manifold pressure.

Maglev, feel free to roll the dice...it's your car.