richierich8434 Posted December 26, 2018 Report Share Posted December 26, 2018 Hi Guys, New to the forum and to owning a 720. I just got this truck for free from a friend and want to fix it up. (not for everyday driving lol) I would like to swap out the engine since this one has a blown head gasket. What engine could I put in this truck with it bolting up to the current mounts and transmission? I would like to make this fuel injected. Would i need anything besides the engine and ecm? The engine that is in the truck now was rebuilt however they did not do it right so water is in the oil. when we got it back from the shop it was out of time. I fixed the timing issue and then it blew the head gasket. Anyway, what would be my best options? Thanks in advance for any help. 1 Quote Link to comment
datzenmike Posted December 26, 2018 Report Share Posted December 26, 2018 Cheapest, easiest, is to replace the head gasket, after all, the engine was rebuilt and should have lots of good miles left in it. The water in the oil is from the blown gasket, which may have been from incorrectly putting it on or torquing the head or not checked for warp. The Z24 is commonly known for blowing the head gasket which is unfortunate because it's easy enough to prevent. If you are not doing this yourself, don't go back to the place that did the work for your 'friend'. If you do it yourself and have a socket set you can do for the price of a NAPA gasket, about $25. The head can be checked for flatness with a straight edge and you easily can hand sand it level in under an hour yourself with a sheet of glass and a couple of sheets of sand paper. There is no other engine that will fit your engine mounts. But the KA24E or KA24DE from a D21 Hardbody is the closest and will bolt to your transmission. A member here sells pre-made engine mount brackets for the KA that should bolt to your 720 rubber mounts. A rebuilt KA is not going to be cheap (used is no better than the Z24 you have) and you will need a high pressure fuel pump, match to your exhaust down pipe. Probably your rad will work. The D21 Hardbody EFI wiring is part of the Hardbody truck's wire harness and very difficult to separate, and then you have to graft it into the 720 harness. There's another member who makes a Can Am box that makes the connecting easier. Replace the head gasket. 1 Quote Link to comment
Stoffregen Motorsports Posted December 27, 2018 Report Share Posted December 27, 2018 Richie RIch. If you are rich, then go engine swap. Even the basic EFI motor swap, done by yourself, will cost $3500 in parts. $7500 to have it done in a shop. That's just a guess, but time adds up. No engine other than the Z series will "bolt in", but the KA24E truck motor is the easiest EFI motor to swap in. And with about 50 more HP, stock, not a bad way to go. 1 Quote Link to comment
richierich8434 Posted January 14, 2019 Author Report Share Posted January 14, 2019 Really i just want to change this thing to EFI. Im looking for anything to make it a little faster. could i just keep the same engine and add the EFI parts? What would I need? 1 Quote Link to comment
bottomwatcher Posted January 15, 2019 Report Share Posted January 15, 2019 Nothing makes the Naps z any faster. It is dead nuts reliable in stock form with a installed and maintained head gasket but nothing can add any real horsepower due to head design. 1 Quote Link to comment
datzenmike Posted January 15, 2019 Report Share Posted January 15, 2019 EFI won't make it faster. It may improve the mileage a bit. After April '85 the Z24i was EFI. 1 Quote Link to comment
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