Datsun 620 With Z24 Block and L16 Head Swap

[Beastlikethat1]

Hello all, I just finished my 1977 Datsun 620 engine swap from an L20B to a Z24 with a L16 head! I want to make a "build thread" with picture thumbnails but can't seem to figure out how others take the image link and get it to pop a thumbnail up!? Anyways here's a few pictures of the process and once someone helps me with the way to get the thumbnails to pop up on here I'll go into details below!

https://imgur.com/a/rEqCW

[banzai510(hainz)]

WHAT WAS WRONG WITH THE L20?

I think you went backwards putting that L 16 head on there.If anything people put the L20 head on a Napz Z block

[Stoffregen Motorsports]

Cool. Let's see those pics.

[datzenmike]

Just to be clear your L16 head says 210 just behind the fuel pump???

 

 

L16 head is not a good idea. First the compression will be about 10.3 and will ping like hell. Second the L16 head has small valves and ports... the last thing you want for an engine that is 50% larger than an L16.

 

Use the U67 head from the L20B. Compression will be about 9.4 and more manageable. The U67 has much larger valves and intake ports and has a very slightly hotter cam that the 210 head. Use the L16 exhaust manifold.... perfect.

[Beastlikethat1]

First question: I liked the L20 but it felt gutless. Granted I do want to rebuild it and do some modifications to it. The deal was, my hitachi carb was in need of a rebuild as the car would barely run anymore. It had the intake style where the exhaust manifold was built into it and the manifold was leaking bad. Long story short it was either buy a weber, intake and headers for probably $500-800 or get mikunis, built motor, 5spd trans, gauge cluster and about 5 boxes of new parts for $850. 

 

Also I posted a link with pics but I have many more

 

And yes I thought it would have all sorts of problems but strangely running on 93 octane and after tuning there's no misfires, knocks, pings ect. the pickup and torque is amazing on it. I've accidentally spun tires in 2nd without trying. I'm not sure if it's the cam grind or what but I was going to put my L20 head on it but I have no plans for that now.

[Beastlikethat1]

Of course I will make a walk around video of the truck for you guys and let you hear it run and put my gopro on it and drive it around so you guys can see what you think!

[datzenmike]

The U67 head will do the same and more.

 

That 5 speed will work if you take the front case off your 620 transmission and swap it onto the one from the 720. Right now it will bolt up but be leaning toward the driver's side. That's no good

[Beastlikethat1]

I'm using the stock L20B 5spd right now and everything bolted up as stock also here's a little clip (backtracking) of the first time it had ever started. https://www.youtube.com/watch?v=2VnJXwf10Zk

It has a full SS exhaust on it now, and of course timing wasn't set and carbs weren't tuned or jetted yet.

[banzai510(hainz)]

If its running good just  leave it.

[datzenmike]

Didn't know you had the optional 5 speed. '77 was the first year. Keep that one as a spare. Did you use the L20B oil pan? Because the Z24 will be on an angle.

[Crashtd420]

Didn't know you had the optional 5 speed. '77 was the first year. Keep that one as a spare. Did you use the L20B oil pan? Because the Z24 will be on an angle.

One of his pics shows the block is at the lseries angle and the bottom of the pan is not level .... I questioned if that was ok or not....

[datzenmike]

It will work but the dip stick will need to be calibrated or you'll read full but be lower than indicated. L20B pan will fit.

 

What timing cover did you use????

 

 

 

There is no replacement for displacement.

 

Hmmmm... I have a spare Z24 sitting in the back yard and a U67 head and a spare reground cam

[Crashtd420]

I thought maybe the oil pick up tube or something might be effected....

What about the crank vs the oil level?

I read if to full you can turn the oil foamy or something...

I only ask out of caution.. I would hate to see the motor get starved for oil or something happen after all that work..

[datzenmike]

That amount isn't that radical. Like driving with two wheels up on the curb. Might be different if you were rock crawling or auto-Xing.

[Beastlikethat1]

It will work but the dip stick will need to be calibrated or you'll read full but be lower than indicated. L20B pan will fit.

 

What timing cover did you use????

 

 

 

There is no replacement for displacement.

 

Hmmmm... I have a spare Z24 sitting in the back yard and a U67 head and a spare reground cam

If I have to be honest I'd have to ask the guy who built it about 13 years ago lol. I know that it was extended and welded on. He made a "custom" dipstick for it but of course it was for the Z24 oil pan so I swapped oil pans and looked up the recommended oil capacity and drill pressed holes in the dipstick accordingly. I do wonder what the L20 head would be like on it, though I have that perfectly good engine in the shed, kind of thinking about finding another truck/ sedan body. Maybe even a roadster and build it up first.

 

I myself need to do more research on everything but thank you all for the questions! I've been driving it on 10W40 synthetic after I ran the break in oil for about 2 weeks now and driven on and off highway without issue so far!

[Farmer]

[Farmer]

Hello all, I just finished my 1977 Datsun 620 engine swap from an L20B to a Z24 with a L16 head! I want to make a "build thread" with picture thumbnails but can't seem to figure out how others take the image link and get it to pop a thumbnail up!? Anyways here's a few pictures of the process and once someone helps me with the way to get the thumbnails to pop up on here I'll go into details below!

https://imgur.com/a/rEqCW

I just went to the account. right click on an image, find " copy image location" Click on it..  Go back to ratsun, find the image icon (looks like a tree in a square). click Icon and paste in url bar. Press ok.  Done

[wayno]

I just go to the account(click on your link), right click on the image I want to post, select "copy image", come here and paste it in the field.

 

I was unable to find a photo of what you use for a front timing chain cover, that would be very interesting for several on here.

To me it appears the Z24 cover was used, it's nice that Nissan didn't change all the little parts and they interchange like the lower radiator hose fitting.

[datzenmike]

I think Sealick used the Z24 timing cover and was able to reconfigure the head gasket enough to seal it. The bottom rad hose inlet will probably work but is not the same as the L series because the 720 alternator has more room because the idler arm is on the outside of the frame. The 720 rad inlet sticks out more directly, the L series is swept back more.

[distributorguy]

Ditch that restrictive carb and put the twin side draft Hitachi's on.  Or SUs with #7 needles.  The performance gain is stellar and well worth the effort and cash.    I've wanted to build the same street engine, but it appears they are pretty rare in these parts - most were scrapped.  There's a LOT to be gained by porting that head as well.  Tons of material can be removed safely.  

[wayno]

Well that has an L series water outlet on the Z24 timing chain cover as the Z24 outlet doesn't have the fitting for the heater core that points back towards the firewall.

[datzenmike]

I think they have the heater hose but not the bypass hose from the thermostat housing (which is on the intake on a Z series and is plumbed into the heater return). Some or all L28 have the heater return and no by pass either because they are EFI

[wayno]

Well that one has an L series fitting on it, but it appears to be a Z24 timing cover.

[datzenmike]

What picture are you looking at wayno??  

 

 

 

Is the black block with the orange fram filter the Z24??? because that is not an 210 L16 head. Looks like W53 (import JDM) or W58. The W53 has huge valves same as the W58 No wonder it goes so well.

[banzai510(hainz)]

Yeah that not a 210 head. U67 if I can see correctly.  I see a U