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Re: EFI vs. CIS

Just a blurb here, maybe one of the Listers still has the magazine,

There was an article in an issue of European Car about a guy who did a
EFI conversion into a Jaguar, his setup was (if I remember) triple-turbo with
nitrous to light the turbochargers, all controlled by a very comprehensive EFI
system.  The article went into a lot of detail about what was required to get
the system to work  harmoniously, and obviously it was a project that was
"cost no object" (he had custom-fabricated intake manifolds, etc.), but the
guy who did the conversion also sounded like an expert on these systems, so he
probably saved a lot of money because of that.  The article left no doubt in
my mind that EFI can be very rewarding to someone who has the time, money, and
expertise to put into the conversion, and probably once you've reached the
upper atmospheres of what the stock CIS system can do, it becomes an option.
By that time you will have gained a lot of knowledge about the CIS as well and
be in a good position to judge the relative merits of scrapping all your hard
work and shelving it in favor of EFI.  

It sounds like Graydon has BTDT, decided not to further tweak the CIS, and had
the knowledge and the drive to put and EFI system into his car and get it
working right.

When you reach the power level where the stock CIS can no longer deliver
enough fuel, you've hit a point of decision:  do the hard work to get the CIS
to flow more fuel/air _and_ run well on the car, pass emissions, etc., or do
the hard work to get rid of it and put in an EFI system.  On the MC engined-US
cars, you reach this point at about 280-300 horsepower, from what I can
gather.  Up to that point, the stock CIS is inexpensive, reliable, well-
understood, and gives very good driveability.  

To me, it sounds like the difference between asking for a street car or a race
car level of power.  (Obviously I'm only talking about the relatively easily-
modified Turbo Audis here).  And there's a lot you can do at that point to
postpone the decision and get better acceleration as well as satisfy your
thirst for modifying things - try to get the car to lose some weight, for one.
Power seats are heavy.

Best Wishes,