My EFI is alive!

[DFN Doe]

This computer sounds like quite a doit yourself project... I'm sure if
you could put it together as a kit, with a pre-etched board and such,
there would be a some buyers on the list for it... 

I sure am interested.

-Dave Pratt
1970 Datsun 510 2-door
Lafayette, CA

Chris Vondrachek wrote:
> 
> Dimers,
>         Well I did it!  My totally homebuilt EFI project lives.  After fouling 3
> sets of plugs, the engine fired early friday morning, and boy does it purr.
>  I still have lots of tuning to do...the fuel map is really rough and the
> O2 sensor correction doesn't work right....oh yeah there is no acceleration
> enrichment...yet.  But other than that it is totally functional, it really
> does work well.  So like I promised...here are the details:
> 
> Engine:
>  Block/Head-
>         Z-22S block (+0.020), U67 head, 270/0.450 cam, ~10.6:1
>  Intake/Exhaust-
>         280Z intake cut and welded, Z-22E throttle body, L-16 cast manifold (O2
> sensor in down pipe)
>  Ignition-
>         stock breaker points - a really wacky distributorless igntion is in the
> works though
> 
> EFI System:
> 
> TYPE:
> Batch firing Speed-Density (uses manifold pressure and rpm w/ air temp to
> get mass air flow....no MAF box needed, 2 injector events/revolution, all
> four injectors go at once (soon to be changed))
> 
> COMPUTER:
> custom designed by me, based on Motorola 68HC912B32 16 bit/16 MHz MCU
> 32 kbytes Flash EEPROM, 2 kbytes RAM, 768 bytes EEPROM.
> 
> SOFTWARE:
> also written by me, over 5 pages of assembly code plus 2 fuel maps
> 
> SYSTEM HARDWARE:
> Motorola MC33293 quad fuel injector driver, misc signal conditioning, power
> supply and filtering circuitry all in a Radio Shack metal project box :)
> 
> SENSORS:
> manifold abs. pressure (MAP), manifold air temp (MAT), coolant temp, Lambda
> (O2) system triggering/rpm signal from coil.  (MAP, MAT, and CLT are GM, 02
> is Bosch)
> 
> INJECTION STUFF-
> 4 Bosch injectors out of a Z-22E, also a cold start injector in the plenum,
> Nissan fuel injection pump (~60 psi), system pressure 40 psi, pressure
> regulator, custom tube fuel rail, idle air valve set for about 5 minutes
> from cold.
> 
> FUEL MAPS:
> 2 maps: base map and correction map, user defines base map used for open
> loop, computer modifies correction map to compensate for above map and
> "other" factors when in closed loop operation. user can modify and reload
> base map in 10 minutes max. allows sloppy rich or lean and clean A/F
> settings.  10 MAP levels, 15 rpm levels (will be 15 map levels and 10 rpm
> levels soon), maps stored in EEPROM for easy modification.  lots of changes
> to come in this area....
> 
> Next step is finshing/refining the system including testing, bashing,
> dropping etc to see if I can get the system to hicup.  If not the next
> phase is to pull the engine off the dyno and drop it into my 2dr for some
> serious performance analysis :)  It will be at Shasta...heck, I might even
> have the turbo on then too...ah we'll see (10.6:1 + 7 psi = knock, knock,
> clank!).
> 
> Well those are just a few of the details :)  If anybody has any questions,
> comments, political statements etc I'd be happy to hear 'em.  And yes I do
> have some pictures of the more important processes...when I get them
> developed and scanned....I'll post.
> 
> Chris "EFI'd" Vondrachek
> 
> 
> /////////////////////////////\\\\\\\\\\\\\\\\\\\\\\\\\\\
> \\\\\\\\\\\\\\\\\\\\\\\\\\\\\///////////////////////////
> Chris Vondrachek
> chris at egr.up.edu
> 
> winter: EE student (junior), University of Portland
>          President & Founder of the U of P Formula SAE Team
> summer: Datsun 510 nut, in my garage: Newberg, Oregon
> 
> '70 2dr 510 - (soon to get a EFI'd LZ-22)
> '71 4dr 510 - (will get hand me down L-20B from above)
> '71 2dr 510 - (race car project...someday)
> '73 2dr 510 - (parts car)
> '85 VG30E - (twin turbo EFI engine by Shasta '99.....or I own Kelvin a pizza)