[Gmecm] Reasonable configuration?

[Jay Vessels]

Hi there!

> collecting donor parts for a Stalker V6 kit car. I have a 3.4L V6 from
> a 93 Camaro I'll be using and would like to run TBI on it. I know a
> number of people do this swapping this engine into S-10s, running
> either a 4.3L V6 TB on it or at least swapping the 4.3 injectors into
> the 2.8 TB. Either way they keep the stock 1227429 or 1228062 ECM and
> chip.

The 1227429 isn't well hacked and wasn't used for very long, so I'd 
avoid it.  I happen to have two of those ECMs, and The Plan is to go to 
the '8062.

The 1228062 ECM is a good choice for a stock 3.4 Donormaro engine. 
Start with the 2.8 cal, adjust it for the displacement change and 
injector size change (if you use 4.3 injectors, regardless of the TBI 
used) and start from there.  The '8062 / 2.8V6 combo is supported by 
TunerCat so if you plan to use that software you're set.

You could use the 1227747 ECM but it's more tuning work since you don't 
have a reasonably close baseline, and I'm not sure there's any benefit 
to using that ECM either in tuning flexability or cost.  Why not make it 
as easy on yourself as possible?

An advantage of using an '8062 with (almost) no chip changes is that you 
can duplicate the 2.8 TBI setup's wiring and get the engine running as 
good as stock.  It's a lot easier getting a conversion working if you're 
not fighting custom changes to your installation as well as the 
conversion itself.  Once you get the system running and the bugs out, 
you can dial it in.

> Also, can I use the DIS from a 3.4L Camaro? From what I've been able to
> gather, it seems that the interface is the same as the HEI distributor
> interface.

There is stuff in the archives about this, but if memory serves the DIS 
reference is 60 degrees out of phase in relation to the distributor. 
So, yes it can work but you'll need to adjust the base timing in the 
chip to match.

> One final question - is there a good reference for learning how to
> tune? 

Check the GMECM page for Bruce Plecan's documents.  That's a good place 
to start.

Jay Vessels
1982 Chevrolet S-10 Sport, 2.8V6 TBI
1984 Chevrolet S-10 Sport, 3.4V6 (TBI pending)