Engine dyno for EFI project

[Jonathan R. Lusky]

Bruce Bowling writes:
> 
> I had an idea a while back, but never followed up on it.  Why not use a
> calibrated alternator for a load device?  For instance, when you turn
> on the headlights, the engine RPMs drop down a small amount.  This
> drop is caused by the alternator "sucking" up some of the total
> energy delivered by the engine.  If one kept a constant current
> draw on an alternator, a table of rotational torque vs. RPM can be created.
> Even easier if one wants only relative power improvements:  make 
> switchable load that can be electrically switched on and off the 
> alternator (ie. alternator has either no load at all, or a fixed
> electrical load), at at a given no alternator load RPM, switch
> on the alternator load and watch the RPM drop and save this drop.
> Now, after a engine modification, repeat the above - better engine
> power means lower delta RPM (I think).

A standard 60amp automotive alternator can absorb about 2HP I think.
Not much use for an autmotive dyno..

We had a 250HP Eaton Eddy Current dyno at UTexas.  The absorber was a
giant DC generator that took up about twice as much space as my small
block Chevy did.  Water cooled, too.  And the associated power
electronics filled up three 3'x8'x3' cabinets.


-- 
Jonathan R. Lusky                        lusky at knuth.mtsu.edu
http://www.edge.net/~lusky/                 (615) 726-8700
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68 Camaro Convertible - 350 / TH350  \_/ 80 Toyota Celica - 20R / 5spd