blowers, compression, ect...

[Stacy Faught <slfaught@domain.elided>]

Just a thought provoking question here....

If someone were to attach a roots-type supercharger to the front pulley, and rearrange the
airbox/sensor setup on a Bosch equiped 2L, would you be able to leave the pistons alone at their current
9:1 compression ratio while running 5 or 6 psi boost on the blower?  Of course you'd have to have higher octane
gas to prevent predetonation, but I'm wondering if you could get away with 91?  Any thoughts or experience here?
I'm aware that a turbo-d Alfa has to run lower compression pistons, but turbo boost is normally in the 10-15 psi range...

It might be a handy way to add 30-40 HP without a lot of heavy mods....roots-type blowers don't require any lines
to be tapped from the oil supply, and it would save the hassle of custom designing a header...

Of course the other issue is if the L-Jet system will allow for the higher air flow---the computer should be able to 
calculate the proper injector opening time, but will the stock airflow meter open to maximum before full throttle
has been realized, and will the injectors flow enough fuel?  If the thing pegs out at 4000 rpm, you'd have a nice low
end boost in power, but the top end would be flat as a pancake, and you'd proabably only get 10-20 extra horses 
out of the system...

I think the airflow meter might be the limiting factor here, since you *should* be able to replace the injectors fairly 
easy---I believe the Bosch injectors use standard fittings across most of the line, but I could be wrong here too...
Heck, you could probably even take the injectors to a good shop and have them modified...

Or mabye you'd have to replace the whole injection system, which then
doubles the cost (easily) of the modification--still not out of the question but a much more involved project :)

I was rummaging around in my spider the other day, and suddenly realized that it wouldn't take much to fit a small
blower on the left side of the engine, where the current airbox/meter is...the meter would fit under the blower, and a 
cold air intake could be fitted to the current airbox mounting points...it would be easy to route a new belt off the existing 
pulleys to the blower, so the only real hassle is making brackets that will hold everthing in place without straining the belt.
A roots or screw-type blower would be great(IMHO) with the Alfa 2L, because it makes most of its boost by 2000 rpm, so
you'd get a very nice low end----a turbo would be better for racing, since the revs are high and you can generate 
amazing amounts of boost, but for street driving, a blower seems more apropriate...OK, your mileage will go down the 
tank, but you can't have it all :)

Has anyone done this, btw?  I've got bigger fish to fry right now (a grindy 2nd gear, whining rear diff, and a tangle of a 
passenger power window regulator that looks like something run through a blender, not to mention the most bizarre 
vibration that occurs only when the planets are aligned properly and I have a blue shirt on), but mabye someday...lol
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