1953 GMC w/Chevy 235 convert to TBI

Hey everyone, as per the title I’m looking at converting to TBI with a late 80s 4.3 throttle body. I see lots of good info on here and elsewhere on how to do it. My question is - should I go with a 1227747 ECM for now or jump right to a Speeduino/Megasquirt setup? A stand-alone ECU setup would be new to me but I see it as extremely usable for future performance plans and also a bit more $$$. Has anyone converted a similar engine to provide some pros and cons? I would purchase the kit pieces this summer to get ready to convert over next winter. I have some experience with HPTuners and EFILive and have access to some nice Megasquirt training videos from HP Academy.

Thanks in advance!

Hello! Welcome to the forum.

There are advantages to using parts that can be found in wrecking yards and in parts catalogs. I would recommend matching the throttle body to the engine power level. A stock 235 does not need the same amount of fuel and air as a stock 4.3. A better match might be to use a 2.8 TBI unit. 7747 is a good ecm choice and they can still be found reasonable inexpensively. I used one in my '57 truck for years before moving to a later pcm. Are you going to buy tools to read and write chips?

Thanks I’ll keep the smaller throttle body in mind - on another forum I’ve heard mixed reviews about if they flow enough. Yes I would look into possibly getting the tools I would need for the GM ECM. I have a few for OBD 2 vehicles.