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Re: high altitude tips?



Walter asks:

>Date: Sat, 10 Oct 1998 02:29:38 EDT
>From: WKPII@domain.elided
>Subject: Who has high altitude tips?
>
>Hello,
>
>Other than a Jim C chip, what mods will help get back some of the
>power my '85 535i loses here in the mountains of Colorado.
>
>Walter

Well, Walter, Dinan (and others) make a nice turbocharger set-up for
your car that should give you back all the missing power, and then some!

OK, sarcasm aside, at Dinan's tech session a few months ago, Steve
Dinan explained that the formula for engine power had 3 variables:

Displacement
Cylinder Pressure
RPM

Most of the easy bolt-on, plug-in mods are intended to get slightly higher
cylinder pressure or RPM.  However, at altitude (Rocky Mountains) you
have a serious cylinder pressure deficiency.  Your atmospheric
pressure is lower there than it is for those of us that live closer to sea
level.  Forced induction gives you a real big bang for the buck by raising
your car's personal "atmospheric" pressure, so to speak.

The Dinan kit is quite expensive, and I don't know the prices of other kits. 
I haven't seen any supercharger systems for the E28 535i.  But, this
would be the best solution to your power loss.  Even an engine rebuild
that increased displacement would not increase power as much.

Scott Miller
Golden Gate Chapter
BMW CCA #44977

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