<E30, M42, '91> Perf upgrades

[Mark Cory Davis <mdavis@xxxxxxxxxxxxxx>]

I'm considering a Jim-C chip.  Is there any reason to get a different chip
or none at all?  Has anyone experienced the difference in a '91 318i (E30
body, E36 engine (M42))?

I'm also considering a K&N air filter.  Is it true that this will decrease
the life of the engine by allowing more contaminants into the engine?

Does the Jim-C chip need to know about the air filter configuration?

I'm considering a switch from 14" to 15" wheels.  Will this make a
significant difference in the cornering?  I will only consider factory
original wheels, so 16" is out of the question.  So, for 15", what did BMW
offer in '91?  205/55 215/55?  Recommended tires?

Did I miss any other obvious upgrades?  I'm not willing to alter the
suspension at this time.  Also, what kind of HP improvement could one
expect from a perf. exhaust for this model vehicle?

Thanks for the insight.  Regards, Mark
- --
Mark C. Davis
mdavis@domain.elided

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