Thread: computer

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does anyone know what has to be done to eliminate any computer controls on a 454 in a chevy 350 chassis so I can put it in an old truck? specifically a 72 gmc. def want to get rid of computer and any emission stuff not needed for a 72 gmc.

Traditionally, the EFI is pulled and a carburetor slapped on.

I'm afraid I'm not a modern engine guru, but I suspect you need more info before a complete answer can be given. Please tell year make and model of the 454, and if it is complete.

Also your 72 may have some rudimentary black box to deal with as well.

From your question I'm assuming that the 454 is an ECU (Electronic/Engine Control Unit) engine, where the injection and timing are controlled by the computer/ECU. You'll need a new intake & carb, plus a new distributor and should be good to go unless I'm forgetting something.

Depending on the engine config you might also have to get a marked damper and pointer for timing purposes. Also, you may have to consider the accessory drive belt arrangement, you can't mix parts from a serpentine version versus the older V type (e.g. rotation of water pumps are typically opposite from one another)

ok heres another idea- what about taking the ECU out of motorhome with the tranny and motor and putting the entire mess in the 72! Is that even practical? The motorhome is parts only no title

Originally Posted by back in bus.

ok heres another idea- what about taking the ECU out of motorhome with the tranny and motor and putting the entire mess in the 72! Is that even practical? The motorhome is parts only no title

You bet!! You'll need the engine & tranny, as well as the ECU and all of the engine/tranny wiring harness. That's a slick way of doing it, and you end up with all of the EFI operational, as well as all of the tranny function. Not a bad way to go at all.

swapping the entire ECM and engine/tranny is possible BUT, depending upon the year, some of the dash/gauges are integrated into the computer. Does the engine currently have a distributor OR is it distributorless? The newer the unit, the more difficult it is to convert.....new motors dont have distributors, sensors feed to the ECM which drive the gauges, etc. Are you experienced at signal level electricity?

Originally Posted by robot

swapping the entire ECM and engine/tranny is possible BUT, depending upon the year, some of the dash/gauges are integrated into the computer. Does the engine currently have a distributor OR is it distributorless? The newer the unit, the more difficult it is to convert.....new motors dont have distributors, sensors feed to the ECM which drive the gauges, etc. Are you experienced at signal level electricity?

In another post it was mentioned that the donor is a '94 or '95 model, so twenty year old technology which I'm thinking was still a distributor, and not overly sophisticated. There's guys who will take the ECU and harness, and send it back minus all of the "extra" wiring, and even stripped of VIN and security information (or linked to the right VIN) on the newer stuff.

thx for info. the 454 is a 94 for sure. it is in a motor home that is a 350 chevy chassis.
It does have a distributor and a carburetor. I did notice computer sensors in the manifold. sending the ecu out for a cleaning sounds like a perfect option.depends on cost. anyone know who does that? If they do clean it I suppose I can install regular gauges ( not fed by ecu) so I would thing only motor and trans is controlled by ecu. since its a 72 truck it is exempt from emissions. maybe I can loose some smog crap too. I know nothing about the ecu era but learning a little bit. Sure would be nice to drop that 454 in the 72. Would actually save me $$ since the 402 needs work. I have been told I can sell that block for $$ on ebay. Who knows, might get a wild hair and rebuild it once its out.

Ditching the smog stuff can really throw the ecm for a loop. Research into it first.

Another slick option is to transfer the gauges too. Might not even be that tough.

Also, I saw a stand-alone throttle body injection unit, self-learning, for under $600. Complete kit, even including fuel pump. Considering you can pay easily $$400 for s carb, makes it really affordable.

Wait, that kit was for a Chevy 350. But there is bound to be something equivalent for your application.

thanks for info. What actually got me started on this possible engine swap in the first place was some guys on the forum (BBC) suggested that if I was going to fix the 402, I might as well do it to a 454. Just so happens I have one I can have for free along with a TH400 tranny. rsspears responded that it is possible to send the ecu out for a "clean job eliminating parts of the harness not needed or not being used. That seems to be the perfect scenario, if the cost is reasonable. should be less that buying a controller for the tranny or even the throttle body u mentioned, even though they both are possibilities. as far as using the motor home gauges, for me that is not an option because I am building a trick truck to sell. I do want the option to re-configure the dash with some new nice gauges. It might be possible to do that with the ecu and harness as is but I do not know if you can get replacement gauges that are stylish that will connect to the existing ecu harness. haven't researched that yet. I do want to keep this as simple and free of "potential bugs" in the future. Thanks a lot for your input. will check out that throttle body thing .