ignition only ecu's are costly too.
iv just got one custom made for the 1ggte running lpg in the ke70. lookin at around 1100 AU$ for ignition only...so hmm
as bill says, you can get away with a unit with onle mach advance, but coz I'm turbo's i need boost retard. something to keep in mind if you have any future plans for forced induction.
also the price of twin webbers isnt gonna be much less than the price of setting a car up for efi in my opinion.
and then you have issues with having to tune, and your never get as gooder tune from carbs as you are an ecu. also an ecu will adapt to all conditions whereas a carb has to be tuned to the weather, so a retune for summer and winter is required if you want best performance.
remeber, carbs are old school for a reason.
but lpg carbs rock! its half the prive of petrol, it sounds like a carb'd engine, and you get the same power as fuel if you run them on dedicated lpg....
plus you can up compression and advance the spark :D
but i degress...
one thing i wondered is: isnt the 4a-c rad gonna be a little hard pushed when you have a 4age workin its titties off ?