911 Ease of Supercharging or Turbo Charging

I am considering the purchase of a last 70s early 80s Porshe with the idea of modifying it to suite. Perhaps put a slan nose kit on etc...
I have some experience with expensive cars having a Jaguar XJS for many years of which I have been reasonably pleased and is my daily driver.
My mechanic used to work at Down Town Fine Cars (Toronto) where they serviced mostly Jag's, but also Porshe's and Ferraris and he now builds a lot of custom cars.
I discussed with him buying the 911 as above, he recommended buying a late 80s model the rational being that cars with electronic fuel injection and mass air (???) are easy to turbocharge / supercharge. He indicated other models could be turbocharged / supercharged with not as much horsepower increase. In other words words without the mass air I could only expect a 50 hp increase, whereas with the increase could be has high as 200 hp.
My idea is that if I am going to go to the trouble of upgrading to a Turbo body, I would like to get turbo performance. The suggestion was made to go to a supercharger and not turbocharger as there would be little performance differance but less engine modification would have to be done. Appearently the enginee compression should be reduced in an Enginee if it's turbocharged in order to avoid damage to the head gasket which usually involves replacing pistons.
I have tried to read a Porshe buying guide but it doesn't seem to indicate which model of Porshe 911 I can expect to meet the modifications (ie. the earliest year).
If I am going to partially butcher a car I don't want it to be an expensive one.
Mark
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On Sun, 16 Jan 2005 13:36:51 -0500, "Mark K. Lathem"

    First, let me point out that this is unnecessary - Porsche already made the car you're looking for, and it would be cheaper to get a 911 turbo and upgrade it's performance than it would to take a N/A 911 and start from scratch. Good as your guy might be, I don't think he's the equal of the engineers in Stuttgart. You could also get a 944 turbo and upgrade it or take a 928 and add a supercharger kit, and both would stomp most any 911-based turbo into the dirt for half the money.     However, if you're going the hot-rod route, the usual route is to take a mid-70s 911 coupe - these are lighter and less complicated, frequently have bad engines and can be found cheaply, and have the beginnings of galvanization for rust-proofing.     Lastly, the current Porsche hot-rodding formula is to skip forced-induction altogether and go for cubic inches, swapping in a later model 3.8L engine into the older, lighter, simpler bodies.     Emanuel
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I heard rumors of someone putting a 2.7 litre Carrera motor into a 914 that had previously had the 1.7 litre Volkswagen 4-cylinder. The claims made it sound very fast although I'm not sure if any of it was true.
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wrote:

    Definitely true - the 914-6 had a Porsche 2.0L six cylinder in it and people have put in 2.7 and 3.0 liter engines, as well as some small block V-8 engines, into the 4-cylinder models to upgrade them.     Emanuel
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1983 Porsche 944 Guards Red/Black
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We have owned one of the V8 911 conversion cars and it was a nightmare. Over $45,000.00 was spent on this car by the time it was sold and it still had problems.
There are always the "exceptions that prove the rule" but most of the V8 converted cars we saw when we had one never worked correctly either. Every one was "Oh, It's the greatest thing in the world", but after talking for a while it was clear they just didn't work.
Stick with the Porsche engine, and go for the bigger displacement.
Just my .02
CCC

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Buy a late 80's factory turbo and go from there. You have all the factory engineering parts required and can safely increase boost with a larger intercooler and a different pop-off valve spring...and maybe a revised chip.
The body work required for a slant nose would apply equally to any project car...but at least the turbo already has the wide body and suspension upgrades.

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