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bigmoose 89 iX
11-30-2005, 07:38 PM
I figure I should go to the authority on German Diesels. Being the E28 524td was only in the states from 85-86, there isn't all that much information on them.

My neighbor has an 85 BMW 524td that he is putting up for sale. I did a compression test and 2 cylinders are about 25% lower than the others.

The body is flawless, garage kept, and the interior is spotless. What can I do to rebuild the engine, increase the hp/tq & fuel economy? I'm considering a greascar tank for the spare tire well, and I know a source for an alpina trunk tank that mounts on the rear shock towers. It woul be nice to go 1200+ miles on veggie oil & biodiesel. Stock tank is 13 gals, spare tire tank is 15 Gal, and the alpina tank is 9 gals I think. So if I could get 40 mpg or more out of the car (stock is 30-35), I would still have gas left in the tank and go 1200+ miles.

What would boring & stroking the engine do to it? Bigger turbo? Lowering the compression & cranking the PSI up? This engine uses a mechanical fuel pump. How could I get more fuel into the engine? I guess in diesel engine, power is made from fuel. Larger intercooler? Camshaft, BMW had 2 or 3 different cams, depending on euro car and turbo/non-turbo What about the exhaust? The intake manifold? What about a variable geometry nozzle turbo? What about the exhaust manifolds? Any way to increase efficiency from those? A TCD manifold? Equal length tubular? Propane or water/methanol injection? Larger intercooler/aftercooler & maybe mor CFM cooling fan for the radiator?

The biggest drawback with this car is the steel block & the aluminum head.

I'll go with Amsoil synthetic lubricants and their bypass oilfilter to keep the oil cleaner & lasting longer.

A 5 speed conversion, lightweight flywheel, and diff swap might
give this decent acceleration. But then again, swapping the diff might kill the fuel economy I'm looking for. Being diesel engines have a much smaller sweet spot than gasoline engines do. But I can find a 6 speed BMW transmission from the E36 M3 engine that will bolt up, I just have to adjust the shift linkage to compensate for the 10 degree rotation.

Any thoughts? Waste of money/time given the materials of the block & head?

Possible sollution for reducing heat in the head is ceramic coating the pre-combustion chamber, pistions, and exhaust ports. Any other ways to lower head temps & EGT's?

More info on the engine http://www.bmwworld.com/engines/m21.htm

Thanks,

~ryan

dembooks
01-20-2006, 04:49 PM
figure I should go to the authority on German Diesels. Being the E28 524td was only in the states from 85-86, there isn't all that much information on them. === I have serviced them (I work at a BMW dealer since 1990 - master tech)and I'm a former Star Technician (2 time award winner) with Mercedes-Benz dealer fron 1970 to 1990)

My neighbor has an 85 BMW 524td that he is putting up for sale. I did a compression test and 2 cylinders are about 25% lower than the others. === not good for cold starting, or optimum power. it should have a cylinder leak test next.

The body is flawless, garage kept, and the interior is spotless. What can I do to rebuild the engine, increase the hp/tq & fuel economy? I'm considering a greascar tank for the spare tire well, and I know a source for an alpina trunk tank that mounts on the rear shock towers. It woul be nice to go 1200+ miles on veggie oil & biodiesel. Stock tank is 13 gals, spare tire tank is 15 Gal, and the alpina tank is 9 gals I think. So if I could get 40 mpg or more out of the car (stock is 30-35), I would still have gas left in the tank and go 1200+ miles.
=== slow down Charlie! - first by adding a Aux Fuel tank in the trunk adds another 200+ lbs of weight slowing the car and hurting the balanced handling of the suspension. You would need to change the rear springs to correct the lowered ride height as 'we' did in the late 1970's when all the M-B diesel owners added Aux Fuel Tanks to their trunks. First thing to do is restore the motor so it produces the original pereformance. The automatic trans would also not like you feeding it more power into its 20 year old body!

What would boring & stroking the engine do to it? Bigger turbo? Lowering the compression & cranking the PSI up? This engine uses a mechanical fuel pump. How could I get more fuel into the engine? I guess in diesel engine, power is made from fuel. Larger intercooler? Camshaft, BMW had 2 or 3 different cams, depending on euro car and turbo/non-turbo What about the exhaust? The intake manifold? What about a variable geometry nozzle turbo? What about the exhaust manifolds? Any way to increase efficiency from those? A TCD manifold? Equal length tubular? Propane or water/methanol injection? Larger intercooler/aftercooler & maybe mor CFM cooling fan for the radiator?
===forget all that krap - just restore it back to gettinig full throttle opening, clean filters, fresh injector nozzles, a cylinder hear overhaul, new - free of carbon exhaust system - and yer good to go. But when the BMW 524td is running good - it's still no match for my 1984 W123 300D Turbodiesel on accelaration. The BMW DOES have a huge edge on handling and braking!


I'll go with Amsoil synthetic lubricants and their bypass oilfilter to keep the oil cleaner & lasting longer.===MOBIL 1 DELVAC is good to drink also.

A 5 speed conversion, lightweight flywheel, and diff swap might
give this decent acceleration. But then again, swapping the diff might kill the fuel economy I'm looking for. Being diesel engines have a much smaller sweet spot than gasoline engines do. But I can find a 6 speed BMW transmission from the E36 M3 engine that will bolt up, I just have to adjust the shift linkage to compensate for the 10 degree rotation. ==== still not listening - lightflywheel in a diesel!!?!?!??!?!

Any thoughts? Waste of money/time given the materials of the block & head? === buy an E30 M3 and be happy ! then you bore, stroke, turbo, no flywheel, 6-speed yerself to xtasee.

....just my $20.02 wurth


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