Re: personal D-Jet opinions (long)

["Gregory M. Merritt" <gregm@engin.umich.edu>]

On Wed, 28 May 1997, Dirk Wright wrote:
> I believe I can say that. Since I work at the Patent Office, I looked up 
[snip]
> Documentation: There is no schematic for the ecu box - it's proprietary, 
> so you can't repair it and you can't diagnose it. Weber carbs have lots 
> of documentation for both diagnosis and repair. Additionally, if you want 

	Fair enough!  You're quite right.  On the other hand, *if*
you're lucky enough to find them, people often practically give away
ecu's...

> to increase the performance of your engine, you'll need to change the 
> fuel system. Since there isn't much information on D Jet, you're 
> basically guessing in order to get more fuel out of it (or change it's 
> responsiveness). Jetting for Weber carbs is a well known science (and 
> art). 

	I agree with you 100%; modifying your D-Jet engine is inviting
a heap of trouble.

	On the other hand, a company does sell high-performance D-Jet
modification equipment; I'm attaching info from an ad of theirs at the
bottom of this message.  I'd be curious to know if anybody has experience
with this company!  (Standard disclaimers apply.)

> Cost of repair and availablity of parts: D Jet parts are becoming hard to 
> find and are much more expensive than Weber parts. For example, both the 
> wiring harness and the auxiliary air valve are unavailble new for my 914. 

	I agree that availability of new parts is a dismal situation.
'Tis why I collect spares from swap meets to keep mine going... and
for every carb conversion, a nearly complete set of f.i. components
becomes available... (until they're all gone;)

> After 20-odd years, the wiring harness in any engine will be a mess. 

	Can't argue with that.  On the other hand, a while back somebody
posted here that virtually all of the connectors were available from
their local auto parts house (was it Beck-Arney???).  ...but they weren't
cheap...!

> If the law in your state allows it, I recommend switching to carbs. Fuel 
> injection is great, it's just expensive and not well supported anymore. 

	Thanks for the well thought-out response!  Your points are all
quite valid.  Just the same, I would caution folks to think twice before
pitching their entire system for carbs.  Do it if you must, naturally...
but be informed.

-Greg
'71 squareback
'63 Beetle


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(Grassroots Motorsports, Nov/Dec '95, Vol. 12, No. 6, p. 20)