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Hey there, there's no genV forum, so I assume this is the right spot. I'm getting started on swapping an L83 out of a 2017 Silverado into my '77 280z. Progress will be slow as I'm working on a masters away from the car right now, but I figured I'd post what I've gotten so far. Info seems pretty scarce on these engines as well, so maybe someone will find it helpful. I'll be keeping the engine stock and mating it with a T56. Here is what I'm starting with: Here is the engine and transmission, T56 is out of an 06 GTO. The L83 is a bit weird and the crankshaft is not meant to accept a manual transmission so requires a 3/8" spacer on the bellhousing (not shown, but where the gap between tranny and bellhouwing is. Apparently leaving that out will result in a broken block 😕

Ill Put some more pics of the diff mount/cradle and the trans mount. Yes, doing all my machining on a 3 axis using SolidCam. I buy the Aloding coating and the acid prep/wash from Aircraft Spruce. Its easy to do everything just has to be spotless clean and degreased. I designed and made this diff cradle so many years ago I had to dig up pics. Dont think anybody had something available back then This pic dates back to 2001, thats how long this project has been going. All the turned parts are done on a manual lathe and I did not have CNC back then so its all done on a manual mill as will. All 4130 steel, pretty light actually. Just a hobby so no hurry I guess Front diff mount is two OEM mounts cut in half and weled together, I integrated the solid mount into it as 1 pc. Here are some CAD pics of the mount. I actually have moved the engine back about 1 inch so I needed to make a new trans mount. Wanted something to go with the new design front motor mounts Ill show soon when I finish up the cross member. The bushings are from the outboard rear control arm urethane kit. I Its steel and aluminum contruction. I still need to put a finish on it. But I wont probably use it now as I am going to replace this S15 Trans with a Nismo 6 speed. So Ill have to modify the design and make some new parts. Front crossmember and Front suspension coming soon

Maybe its time for an update. Car is doing well, mostly working on less noticeable things. The transmission I had was completely shot. Most gears anywhere near the synchros were pretty worn. With the price of replacement parts for the T56 lately I decided I might as well just buy a new magnum for slightly more. With the engine still mounted forward from other LS swaps, the F-body shifter was a bit too far forward compared to the GTO shifter. The GTO shifter was also just slightly too far back in its original location where 4th gear would hit the console trim. It looks a little sketchy, but I was able to drill new holes and flatten out some features in the GTO shifter to match the magnum shift cup and seal correctly. Original holes were plugged. I also welded on the bad dog frame rails over my existing rails. The rails weren't terrible, but had a couple bad spots that I wasn't totally comfortable with. I installed the 240z e-brake cable in as well. Welding on some washers to work with the larger 280z mounting points. To match the new engine, I installed some 300zxt cv axles that I found for cheap a few years ago. Since mtnickles adapter plates that don't add any extra hub thickness are no longer available I had some machined using a similar design. Also replaced the wheel bearings while I had things taken apart. The silvermine rear brake calipers are a fairly tight fit around the cv axles. I had to bend the e brake mounting point to avoid the flange. The sway bar was also a tight fit. I had originally purchased the T3 rear sway bar but it had no chance of fitting with this setup. The ST suspension rear mount sway bar fits with the spacer on the end link shortened. Swapped in some GTR AP3 side mirrors while I was waiting for the CV adapters to be machined. The ones on the car when I purchased it were some cheap plastic and tended to fall over if I looked at them. Back to some genV related stuff. I didn't have a clutch sensor wired in and apparently the ECU needs to see it. Helps to avoid the ecu getting confused when the load suddenly disappears. GenV engines seem to use a position sensor rather than a switch, not sure why. Engine is running fairly well now on a 2017 Camaro OS. Still have some rev hang issues and needs general tuning, but totally driveable. A lastly I made an airbox for my intake as I try to get things ready for some dyno tuning. First time making a fairly complicated shape from a cardboard template cutout, fairly pleased with the results.

One last thing, the hood just barely fits, but probably wouldn't without modifying the engine mount to let it sit lower. Maybe if the engine was further back it might be ok, but that would still require modifying the vacuum pump flange or the engine mounts to allow the engine to move back further on the mounts. The aluminum foil on top of the throttle body is the room I had left. You can see the foil in a couple other spots was pretty close as well. I had to rotate one of the intake pipe hose clamps as it was just barely touching the hood.

Ok, so things went much easier than I feared. I only had one small issues in my wiring harness. I had wired in one wrong O2 sensor. I've updated the doc I posted. Exhaust went in without issue. That was my first time back-purging and welding stainless. It doesn't look great, but its leak free and shouldn't rust. E Everything else went in fairly straightforward on the hardware side. I had a driveshaft made, dropped it in and was able to get the car moving. All in all, not much different from any other LS swap. On the ecu side I had a little more trouble. When I bought the engine it was out of a 2017 Silverado, but the ecu ended up being out of a 2019 cadillac escalade. Since the cadillac was never offered in manual the engine would run, but it was always expecting feedback from the tcm and even changing settings to a manual transmission didn't help. I had to buy more hp tuner credits, but I eventually got a 2017 camaro OS installed and things worked much better. I also needed to hook up the VSS as several of the ecu tables relied on vehicle speed. The only remaining issue now is that my transmission seems to be pretty worn out. Grinding in all but 5th and 6th gear. So it will need to come out and be repaired. Then I can get back on the road and tuning things up. I also haven't put the hood back on yet, so that remains a potential issue, but I'm crossing my fingers I've got the engine low enough.

Quick trip home, got a little work done. Clutch master cylinder went in with no issue. Nothing too exciting there. Swapped the push rod for the 280z original one and went in fine. Corvette accelerator pedal is in too. Made an adapter to use the original pedals mounting points on an aluminum plate. The plate is fairly thick, so it doesn't flex. I had to space the pedal forward about 0.4" as it doesn't stick out as much as the original one. On the more interesting side, I bought some 2016 camaro headers to see if they would work on the Z. Passenger side needed some work, but I think it is manageable. I made two cuts along the inside of the header to let me bend the header in slightly to get it to fit inside the frame rails. I will have them welded back up. Also removed the flange. It comes out directly above the tension rod mount, but I think I will be able to cut it a little shorter and have enough room to turn the pipe and get around it. I also had to remove the plastic connection cap on the starter solenoid. to make a little extra room. Drivers side fits pretty nicely except for the same issue of the tension rod mount. Again I think I have enough room to route around it.

Here is the picture of the modified engine mounts, you can also see another reason I couldn't move the engine back. The vacuum pump flange on the LT block interferes with the mounts so the mount has very little adjustment to move the engine back on the driver side. I would assume it would be possible to modify the mount to fix this, or maybe even trim off the vacuum pump flange. I made up a transmission mount and got it installed today as well. Its bolted to tabs welded to the frame rails. Here is where the shifter sits with the GTO shifter. No interference in any gear, so I'm happy with where it's at.

Looks like the GTO shifter is about 3.5 inches back from the camaro shifter plus the 3/8 spacer. If the engine is in that neighborhood further forward it will be close. The 2.5 looks good too. I wouldn't slam the hood yet but a good start. HTH, Richard.

Good to know Richard, it looks like the shifter is a little forward of where it was with the old transmission, it would work where its at with the camaro shifter I believe. I'm hoping with the GTO shifter it will be just a little further back as I'd like it a little closer to me than the original position. Forgot to snag pictures of the modified mounts, but I was able to drill new holes in the engine mounts to lower the engine about an inch. From the fender line I'm about 2.25" over, so maybe that will be enough. If not, I should be able to make a spacer to move the throttle body away from the water pump which will allow me to flip it upside down.

Not using the same engine but we are using the same trans (04 GTO LS and T56) The shifter will likely need to be changed. Can't remember how far the GTO shifter is behind the Camaro one I used but it was a lot. This may help with the more forward engine but it will be something to consider. lowering the engine seems mandatory although the Datsun hood has a lot of clearance in the middle, solid 4 inches above the fender line. Looks high in the pic. Keep us posted, cool project, hope problem solving is fun. I found a lot of good info here even not following the 'recipe'. HTH, Richard.

I got the engine in today, I'm using the Dirty Dingo motor mounts and I'll be making my own transmission mount. So first difference between this engine and an LS. It has connections on the back of the engine for the high pressure fuel pump. This means it can't get as close to the firewall as an LS. Theres plenty of room in the front, so engine position is no big deal, however I assume LS engines do need to be near the firewall to allow the transmission to fit around the original transmission mounts. Since I couldn't get this engine too close. I had to cut them off. I'll likely still try to use them as a mounting point for the transmission, but the original flanges wouldn't work. Once those flanges were cut, the engine went bolted in without any interference. I haven't made a transmission mount yet, so time will tell if it will be a problem, I don't think it will be though. That being said, the Dirty Dingo mounts are rather high with this setup. I'm using their adapter plates to use LS mounts with an GenV engine. I'm also using the Holley oil pan, so it has quite a bit of clearance. Clearance is good, but the engine sits a bit high. I'm using a camaro intake and the throttle body sticks up too high. I'm not sure if anything else will also be too high. Headers will be interesting, but I'm probably not doing longtubes. The OEM manifolds won't work, but they aren't too far off, so I think I will be able to find something that works. Anyway, just wanted to get a thread started to at least help me keep some record of the project. Hopefully will finish up a few more things while I'm on break.