Re: Discussion Topic: DIY 320 Turbo (archive)

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: Second, I see turbocharging a 320 as a pretty simple (and maybe not too expensive) task. If you plan to run low boost YES AND YES EVEN IF YOU RUN LOTS OF BOOST.
: pressures (i.e. no change of CR required) it fabricating an exhaust manifold and related exhaust, for intake components you can buy mandrel bent intake tubing and silicone hose from TEP, strapping an MSD Boost computer on to account for timing issues, and adding additional manifold pressure actuated injectors NOT REQUIRED to increase fuel input. Of course this is way simplified and doesn't account for the pains involved in tuining it so that you don't lean or detonate and melt a piston, but it is enough to get some discussion. Presumably a turbo could be accomplished with a blow-through system and carburator ICK. Also, there are obvious improvements like an SDS SDS IS THE WAY TO GO or Tech-II programmable ignition and higher flow injectors to take the place of the add-on injectors (ensures the additional fuel is atomized). Any comments? LOTS SEE BELOW

: Third, what practical problems is one likely to run into. For example, how do you get oil pressure to the turbo? OIL PRESSURE SENDER NEAR DISTRIBUTOR Mount a remote oil filter and tap off that? Are vacuum driven components affected by the positive intake pressures? YES GET ONE WAY VALVES How much does the increased cylinder pressures affect the cooling capacity of a 320? IF THE RADIATOR IS IN GOOD CONDITION NO CHANGE SHOULD BE REQUIRED How do you accurately monitor lean/rich conditions in time to save your engine? EGT AND O2 MIXTURE METER When does a cutting ring head gasket become necessary? DEPENDING ON YOUR TUNING BUT IT SHOULD GO ON ABOVE 8PSI.

: Keep in mind that I studied combustion in school, and was involved in designing the spark and FI maps for our supercharged FSAE car, but it might be helpful for others to discuss the problems with detonation, etc.

: Is this enough to disucss? Is this above the skill level of the board or too off-topic? Lets here some discussion.

Over the last 4 years I have done just that, build a turbocharged system for my '78 320i. I am in the process of building a website which will detail what was learned by my experience.
I started out with the stock efi, modified with a warm-up regulator from an audi turbo. This allowed the car to run around 9psi in the manifold before leaning out. My next step was going to be either a 928 fuel distributor/air flow sensor or a programmable efi. Before I went further I installed two injectors per cylinder and doubled up the fuel lines. I believed the fuel flow was being restricted by the injector, this turned out to be false. I went with the SDS efi system, and bought a '84 318i intake manifold with efi. I have just finished installing the crank triggered distributorless portion of the SDS system.
If your looking for mustang 5.0l (late '80's) performance then 8psi of boost will be enough, this can be achieved with a simple bolt on kit without an intercooler.
If your looking for more, drop me a line I will try to help you decide what parts are needed.

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