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'74 620 KA24E swap. Powder Pr0n inside


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This is my truck: A '74 620 with what I think had 32.5k original miles on it. It came to me with a 3-speed auto, no carpet, and pretty decent paint. 



A friend of my father's said his brother had died and had this truck he used once in a while on the farm that was part of the estate sale. My brother picked it up and buffed the paint, cleaned up the interior, painted the stock wheels and grill black, and put some 3" lowering blocks with the front torsion bars wound down on the stops. It rode a little rough.









Of course he had to try his '88 911 seats in it...Recaro snob


/cry. Wish I could have kept these seats!!!


About the same time my wife and I decided we wanted a truck and I looked high and low at about everything, but fell in love with this Datsun when I saw it. My real passion is BMWs, and my e30 is undergoing a rotisserie-bound, full restoration for fun, and the color choice I had in mind for the Bimmer was an old 80s color called Inca Orange. Enter the orange 620.

e30 with M50 turbo swap fitup for brother on my car (read: I have many tools, he does not)

24175539075_1d422084c8_b.jpgUntitled by Brad Buccambuso, on Flickr


I snatched it up and drove it 190 miles from Twin Falls Idaho to Layton Utah. That 3 speed sucks! I replaced the fuel fill neck and all the vacuum hoses under the hood, air filter, and fixed a short in the coolant temperature sensor and I was back in business. Then the driver-side wheel cylinder went out and was leaking like a mad man, so I replaced the one side...then the passenger side sprung a leak...drums can kiss my ass.


I also picked up these Yota wheels he had on his '02 Tundra, and had to test fit while at his house (because lift) so I'll be powdercoating those



We have loved this thing so far (aside from 3 speed). Took it to a local, monthly car show. The kids love riding in the back of this thing.



I daily this thing to work everyday. Worked late one night last summer and thought I'd snap a quick pic



It's not all clean though. I kept getting water in the cabin and assume the culprit is this:



To remedy the 3 speed, my 280z-nut brother in law, who is also my automotive spirit animal. Hooked me up with one of his many 5-speeds



I found out the hard way '74s have the 5-bolt flywheels after spending hours disassembling a 4x4 D21 at the yard to harvest a clutch and flywheel...but I found an awesome old timer in Arizona with everything I needed, grabbed a 280z master cylinder from my bro-in-law (BIL), and off we go with this awful shift knob but I DON'T CARE BECAUSE THE CAR IS 5 SPEED AND DOES 80 ON THE FREEWAY ALL DAMN DAY.



Well, now I want more power. I really like how this thing sings at who knows what RPMs in 2nd and third, and originally planned on going the EFI (Megasquirt) & FI route on the L18 using some aluminum injector bungs and a home-made intake and turbo exhaust mianfold, but I found this lurking in a local drift classified and decided on a swap.

I even played with the plasma table at work to get a working flange template made; took me a couple of tries.








It's a KA24E from a '90 240sx that just came back from the machine shop with a 3-angle valve grind, block and head deck, .050 bore & hone, crank polish, head port & polish, and flywheel resurface. Came with trans and Exidy stg3 clutch. Couldn't be happier...at the time...

The seller mentioned he couldn't get oil to the head. I'm thinking: "Oh simple, I'll check out the pump and oil galleries and throw it in with ]2eDeYe's KA swap mounts. 







Pieces of timing chain guide all over inside the timing cover, cam key and cam sprocket key had a collision, each piston gouged. Funsies!


Ordered the following so far:

  • goforitoffraod.com centerlink flip kit bushings24274692522_2f28d4d2ea_n.jpgUntitled by Brad Buccambuso, on Flickr 24015131629_8519603710_n.jpgUntitled by Brad Buccambuso, on Flickr
  • euro tail light lenses
  • all new exhaust valves
  • eBay inline fuel pump (have the stainless and bungs to do the surge tank thing, but going to try the mechanical fuel pump > filter > HP fuel pump > fuel rail for now)
  •         Please comment if this doesn't actually work!
  • Maxima fuse box
  • oil pump
  • head gasket and bolts
  • timing guides
  • cam sprocket
  • swap mounts
  • late 620 engine bushings
  • oil and oil filter
  • associated gaskets.

It's all returnable, so I'm bringing the parts cannon to the table to make sure, once the rebuild is again done, I can swap it into the 620 in one weekend. I already have the MSI if I end up going that route, but I'm going to stick with the stock ECU till it's running.


Also powder coating. The valve cover is runny purple spray paint. It's gotta go. I just finished reinforcing, welding, blasting, and coating my brother's e30 suspension, and I think this color, which I liken to Bianchi's celeste green, will look fanfriggintastic on the orange. So that color and this color called cannon grey for the bumpers and chrome light surrounds.


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The 71B truck 4 and 5 speeds are borrowed from the z an 810 L series six cylinder cars. Any 5 speed from these vehicles will fit right in no modifications.


'77-'78 280z

'79-'83 280zx (non turbo)

'77-'80 810

'81-'84 Maxima (gas and diesel)

'77-'79 620 truck

'80 2wd 720 (non diesel)


That's a lot of transmissions out there.

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The 71B truck 4 and 5 speeds are borrowed from the z an 810 L series six cylinder cars. Any 5 speed from these vehicles will fit right in no modifications.


'77-'78 280z

'79-'83 280zx (non turbo)

'77-'80 810

'81-'84 Maxima (gas and diesel)

'77-'79 620 truck

'80 2wd 720 (non diesel)


That's a lot of transmissions out there.

Oh snap.


clean truck. wish i could find 5spds easily...

No excuses. Get 'er done.

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Thanks for the compliments, ya'll. I love the orange a LOT.


My brother in law came up and we got started. He was engine rebuild duty, I was on engine pulling duty. It was rainy and cold and oh so much "fun."

Well, here we were, all prepped up to put this thing back together...seems easy enough...



Prepped the headgasket PO put on but never drove or even heat cycled the engine. We changed to a new head gasket after the head bolt fiasco. New head bolts.



I read the head bolt torque sequence incorrectly by calling out 82ft-lbs...not degrees of rotation. It's 52ft-lbs boys and girls. 52. Fifty-two. 

Math problem for the day:



2 hours later. I would like to attribute our success to vulgarity, BIL tenacity, and multiple approaches to problem solving:



  • Drill it out
  • Drill a hole for the ez out
  • Break the ez out
  • vulgarity
  • Buy 2 mor ez outs
  • Drill out the ez out
  • Fail at drilling ez out metal
  • vulgarity
  • Try to reach in there with a shaved screw driver and a crap ton of tungsten stickout to turn it
  • vulgarity
  • Resort back to drilling
  • Cut multiple ez outs as the pilot holes degraded
  • Vulgarity
  • got the ez out to bite, removed the bolt

Sorted. Thank you BIL.


On with the engine assembly. As I've' mentioned, the PO of this engine was a retard on wheels, and stripped out 3 separate bolt holes in the head: Oil pan, timing cover, exhaust manifold. And started a few bolts in crooked. I bought a tap and die set and got to work. 


Drilled out the oil pan bolt from m6 1.0 to m8 1.25



Exhaust manifold bolt from m8 1.25 to m10 1.5




Was accidentally sent two passenger-side swap mounts (sounds like something I'm supposed to do, Redeye, much love, the mounts are amazing quality)



The replacement and a shipping voucher was sent, that's super nice/responsive/awesome. I ain't even mad (read: I have multiple days left to complete this swap yet..)


Multiple head-to-timing cover bolts missing. At this point, I hadn't tapped the stripped holes yet. I just decided to go to the hardware store and buy long versions of m6, m8, m10, and m12 (incorrect, there aren't m12 bolts on this thing ;) and cut them to length, as needed. Worked out great. I mean, who doesn't love putting bolts in vice grips and using a cut off wheel for that custom fit Nissan can't give you.



Decided to address the 240 trans.

It was, disgusting, but you can see the aluminum shining through like a beautiful sunrise. Took paint thinner, a nylon brush, and a wire wheel on a drill, followed by a gasoline shower to get the metal automotive part visible again. This was after 5 minutes of scrubbing that area. Need an after shot when I get home but it was midnight, I wreaked of gas, and it was cold.



Centerlink time! My BIL tried to get the joints apart with my HF ball joint separator, which is tough as nails, but it was a no go. I'm sure he loosened it for me. I changed the pivot point on it and hid behind the grill like the wussy boy that I am and held the impact on until BANG. Driver side came off clean.

Then the passenger side, which may have been a little bent, went 2x as long with the impact, and broke at the threads, and shot the centerlink 5 feet up in the air, landing here


Too close for comfort.


Here is the joint, and the Goforitoffroad.com flip kit, finger tight. Ordered a new inner tie rod from Autozone Performance Parts and More.


Bog monster. The alternative to filling the joint with grease is baptism by immersion.



I hope this has room to be squished on a wee bit more.



I also test fit my BMW E30 rack out of morbid curiosity. It's about 6" too long...rack & pinion dreams...


This is shiny. I like this.



Soooo, the next two days will be EGR delete, transmission beautification, fitup, and driveshaft shortening, wheel powder coating and tire mounting, and over the weekend, if all goes right, wiring and fuel. Hoping to drive this thing next week!

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More problems:

Was accidentally sent two passenger-side swap mounts (sounds like something I'm supposed to do, Redeye, much love, the mounts are amazing quality)



The replacement and a shipping voucher was sent, that's super nice/responsive/awesome. I ain't even mad (read: I have multiple days left to complete this swap yet..)






Sorry about that.  :blush:

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Enjoying this, especially the bit about drilling and ez outs.....been there. In fact I almost feel like I was just then too ha ha.cool truck too btw

Thanks Jay. It was pure pain.


Got the engine about all buttoned up. Not sure if I'll bother with the EGR delete before I get it running.


Tonight was wiring night 1/don't want to think about how many days it will take me. I'm a wire-tard, but with some guidance, YouTube, and the '74 Factory 620 wiring diagram pdf, I may just get this done successfully. I would appreciate any input. There are some decent write ups, but none with a ton of detail.


My approach will be:

  • Wire in 3rd-gen Maxima fuse box I got of eBay for $15 because it has:



I'll map out the top side once I get further along with my wiring and add the key-on wires under the dash and mount everything up.

Again, an input is appreciated. 


  • 3 relays built in
  • lots of circuits (needed for fuel pump, efi harness, coil, injectors, etc)
  • These are all the output wires that are possible connections


  • 2 larger power input wires on the bottom (10g from battery to box)




  • Internal circuit paths so some fuses are constant power, some are switched through the ignition (accessory, on, start) wires.
  • Splice into ignition column wires and run to the 3 ignition column wires on the Maxima box
  • Affix the fuse box up high in the driver's side footwell, get it running, and eventually tie in the whole truck harness to the Maxima box
  • Still figuring out the starter wiring and how to run things for the internally regulated alternator and the engine harness/body harness wiring necessary, and where to power the ecu from (just a circuit on the fuse box?) but it's a decent place to use as a power distribution post


Cut a hole (that was too big for the harness firewall grommet...sonnofabitch  :poop: Measure twice, and remember your measurements...



Make the hole smooth



Testing the connection by putting the battery back in place, connecting the positive and negative clamps, and testing my 10g power supply wire (solid 10g home wiring, getting changed out for 10g auto wire), with ground going to a known good ground chassis bolt (tested with multimeter from battery + to the bolt)




Placed the ecu here. I plan on fixing it to the firewall up as high as possible with some rubber o rings, nuts & screws.



For your reference and mine, this is the factory diagram for the ECU pinout. If you're unsure of a connection, set your multimeter to Ohms and connect your test leads to the pin and the connector to see if it reads 0 Ohms (the pin is connected to the connector). If your multimeter doesn't give a reading, the pin and that connector are mismatched.


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A couple of updates today.



First, I was just going to slam the engine in and then I saw the EGR rats nest, and...nope nope nope.


Grabbed a piece of scrap aluminum, the egr tube mount thing, and "fabbed" one up with an angle grinder and a drill press. Add copper spray gasket maker and some cereal box and voila.







I read the exhaust manifold bung has a Nissan factory M24 x 1.5 tapered plug, but I got 4 or 5 from Fastenal and have leftover aluminum. If any of you SOHC boys and girls want a plate I'd be happy to make a few more for pretty cheap. Can powdercoat them as well. It really ties the room together with how clean it is







This appears to be a tee off a coolant line. Where does it go?






Am I doing this right? I see a nekkid nipple. Can I just cap that one since I've connected the two near it, and the FPR to another nipple on the back of the intake?






FPR to nipple 24598924265_b12c4cba70_b.jpg



Connected fuel supply with a new e30 filter I had laying around, and return, which still needs a hard line bent back to the tank fill hose vent line for rail fuel return





Got the inline fuel pump wiring laid out with some heatshrink lined up to be positioned for the sharp areas its near on it's way up to the firewall






Larger particulate filter right off the tank





Turned to the transmission next


I had no idea the 2 mounts were so different, but after a no go on the x member when I removed the driveshaft, and found a thread mentioning the 620 trans mount bolting up to the s13 5 speed, I had a go, and took some pics of the differences


Crossmember width:




Quite the mount-height difference!











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IN (but we're in a fight, because it smashed my thumb)

Got the clutch, flywheel, and PP bolted up. Exedy sprung 6-puck outta be interesting.


I want to put the engine in and get it in place so I can measure the driveshaft for shortening, but the throwout bearing felt really really dry, so I've got one on order.
Replaced the shifter box gasket. No spare parts rattling around inside the trans, that's a + amongst the shit

PowderPr0n and Turbo Fantasy Bonus items:
Manifold flange template drawn and transferred to CAD and cut out on some thin sheet for a test:

Can't wait to see the gold Hardbody calipers on this truck and decide on a powdercoating color scheme for the wheels and bumpers
620 pedal set in Canon Grey

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