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48Njim
11-21-2023, 08:31 AM
Newbie here, trying to get back into an old project. It's a '65 Toyota Land Cruiser with '69 Camaro motor/TH350 AT. About ten years ago I tossed the Quadrajet and installed a TBI from a '88 Chevy Astro Van. Its been good enough for the old Cruiser that doesn't get driven to far or to fast but I think it could be better.


If nothing else my understanding of this set-up could be better.


Facts:
'65 Land Cruiser FJ40 with
'69 Camaro engine(HB) 350(5.7L)/300hp w/TH350 auto using TBI from
'88 Chevy Astro Van ECM
SVC# 1227747
Prom: AKMH


Obliviously the engine is 5.7L V8 and the ECM/prom is for a 4.3L V6. If I understand correctly, it would have been better to have used a ECM/Prom for a 5.7L engine. Again, the engine seems to run fine but I suspect I'm not taking full advantage of the bigger engine. This isn't much a problem consider the little Cruiser's original engine was a small inline six cylinder.


Question:


Should/could I swap out installed Prom for a variety more appropriate for the 5.7 engine? Perhaps an ASDU?


Or could tuning the existing chip get similar results? Sorry I haven't dipped my toes in the tuning pool, but I'm interested in trying.


Or leave it and swap 5.7L injectors?


I'll appreciate any thoughts or direction.


Thanks in advance,
Jim

dave w
11-21-2023, 05:01 PM
Gearhead-efi link for 1227747 information: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?304-1227747-ECM-Information-42

Often starting with a chip that is as close as possible (displacement, injector flow rate, and timing table) is a good plan. ASDU is a 5.7 displacement with 5.7 injector flow rates and 5.7 timing table.:thumbsup:

19553

19553

48Njim
11-21-2023, 08:52 PM
Thanks. Makes sense. I really have been reading and searching but..

Can I change the chip only and keep the installed ECM or better to get another ECM with the ASDU installed?
I assume another 1227747 ECM with the ASDU chjp would be plug and play.

Jim

dave w
11-21-2023, 09:52 PM
I recommend replacing both chips as a married pair. Likely the easiest way to get a married pair of chips will be from a used ASDU ECM.

19554

48Njim
11-21-2023, 10:33 PM
Seems like this would do it. Should I move chips or simply swap the whole unit. I assume the wiring and connectors would be the same.

thank you,
Jim

dave w
11-21-2023, 11:25 PM
Either option works, move chips or swap the ASDU computer.