Electrical Supercharger

[Steve Meade]

----------
> From: LotusM50 at aol.com
> To: diy_efi at coulomb.eng.ohio-state.edu
> Subject: Re: Electrical Supercharger
> Date: Friday, May 09, 1997 8:59 AM
> 
> In a message dated 97-05-09 02:26:41 EDT, smeade at deltanet.com (Steve
Meade)
> writes:
> 
> << On my car, a BMW 325is (relatively little
>  displacement of 2.5liters) a regular supercharger kit costs around $6K! 
>>
> 
> That's, of course, becuase they think that BMW owners have lots of money
to
> throw around.  Kits for Miatas, Hondas and American V8's by Ford,GM and
> Chrysler usually cost between $2000 and $3000.

	That's kind of an interesting remark. On the BMW digest many times the
discussion of "Why does a supercharger / turbo setup cost so much more?" We
all put our (often hard) heads together and pretty much realized the
following reasons:

	1. The kits are produced in much lower quantities and fabrication costs
more. This is why Mustang kits are so much cheaper.

	2. *Most* (not all) kits on other cars are less sophisticated
	
	3. BMW owners can usually (not me) afford to pay more

	Sebring, which manufacturers a lot of supercharger kits for Miatas came
out with a setup for the BMW 1.8/1.9L engines at about the same price as
the Miata kit. But we found out several key flaws in the kit that make it
not the best way of boosting power:

	1. Doesn't change engine rom at all!
	2. Relies on knock sensor to "save their butts -- Land Shark" and doesn't
retard timing by itself.
	3. Uses an adjustable rising rate fuel pressure regulator for extra fuel.

	These are serious technical flaws, in a Dinan Supercharger ($$$) one gets
the following:

	1. New higher rate fuel injectors
	2. Custom made and dynoed engine fuel map and timing for the kit
	3. Recalibrated mass air flow sensor.

	It is for this reason and lower volume that the Dinan kit costs so much
more. 

=-=-=-=-=-=-=-=-=-=-=
Steve Meade
smeade at deltanet.com