dbw

with all this talk about superchargers,i thought i'd share my experiences with a factory installation on a previously unblown car.first it was decided to use a roots type positive displacement unit of local manufacture.obviously space was a problem which necessitated the relocation of several major under hood components,steering,radiator etc.of course a bulge or two had to be added to the sheetmetal.the engine itself required little in the way of external mods other than the required manifolding[including a prominent pressure relief valve.]the internal s though,needed more.a beefier crankshaft was installed,as were larger main bearings and a hi performance oil system.a lubrication system for the blower rotor bearings had to be plumbed in as well.as the unblown version had fairly hi compression,supercharging required a lowering of the cr.the factory found a good solution that allowed stock piston/rod assysto be used.the ignition system remained the same but adjustments in the timing were needed to prevent detonation.of course many other minor underhood mods were needed to make it a viable daily driver/racer.i had an opportunity to drive a factory unblown unit and found it a good strong performer but[as we all know]lacked low end grunt.i have had the pleasure of owning and driving a supercharged version on both street and track...it is a bit more of a maintaince problem,and requires more attention to monitor all the functions,but the performance is spectacular!!!it pulls hard from low range right thru to the redline.the extra noise[mechanical as well as exhaust] is most welcome and would annoy only a few.[as a note of interest,the cars were available to the general public thru delalships with a generous warranty,altho hard to obtain as they sold quickly ]the factory conversion was so successful that the unblown version was discontinued,and the blown car remains desirable long after it ceased production...just how long? the last one rolled off the line july 1930..[mine was made march,1930,registered for the street and driven to the monaco grand prix,april 6 1930,where as a factory team car it finished third.the car?? type 35 bugatti.

cdelena

I had an interesting conversation with a couple of mechanics about superchargers. These guys have some experience with aftermarket installs and thought the S2K would be a real challenge.

The first thing they talked about was the broad rpm range since most forced induction is sized for a relatively narrow 4500 rpm band. They though it would not be hard to have a positive affect from idle to 6K, or from 4K to 9K, but thought that idle to redline was too broad a range for off the shelf components. Speculated that a variable drive or dual system development would be big bucks. Conceded that the centrifugal setup (like Computech) would be the way to go but may just be in the was at low rpm.

A lot of talk about engine controls, thinking that they would like to have a lot of control to make it work well throughout the rpm range. Also a discussion about stuff they could not do in the shop because it was not emission certified.

In the end they told about personal supercharged cars. One was a Miata engine that after two years of development was ditched for a small block Ford. And the other was a Mustang that after several engine failures was scrapped for a bigger V8.

In the end this crowd voted for more displacement for a street car rather than FI.