Injector drive circuit mods?

[John Andrianakis]

Dear all,
I have a Weber ecu :W45.06/L20_67. It drives 4 2.5 Ohm injectors. I want to
add another four injectors. I am aware of the special chips by Cherry and
Motorolla that can drive peak and hold injectors correctly but I do not have
the time to source them at this moment. The injectors are driven by BDX53M
power darlingtons with some smaller transistors all controlled by some ICs I
cant recognize.(This might be not correct, I just figured it out looking at
the pcb.)
I think I could possibly try  two options :
1)Install the secondary injectors(they are peak and hold too) in line with
the primaries thus doubling the resistance and inductance seen by each
output transitor. Probably would have to add inductive kickback
protection.Could anyone guess how thta would change the range of the
injectors?
2)Use another set of four same spec output transistors(BDX53M) to drive the
injectors. Connecting the bases of the additional transistors in parallel
with the ones in the ecu. I have no idea how that would effect the driving
IC and or the current regulation.

I am mechanical engineering student so my understanding of electronics is
basic.
I would appreciate it if someone could help me out correcting my thoughts or
pointing out a different-better way.
Thank you very much.
John Andrianakis.

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org