Z24 in a '67 520

[MrGable82]

Hi guys. So I purchased this sweet patinad machine from a guy in KY out of a field. He gave me one extra J13 and 4spd tranny and my delusions of having a nice, simple, slow, classic mini truck were fulfilled. It was only later that I discovered how nearly impossible it is to get an engine rebuild kit, pistons, etc. for the J13. "No big deal." I thought. I've done many-a-swap before to include cutting, welding and fabricating whatever I need. So I began looking for an engine. I saw all kinds of KA24, SR20, L16 swaps that had been done, but there doesn't seem to be many of those around my area. And even when they are, I really don't want most of them because of EFI or an ECM and harness upgrade that I'd like to steer away from. I'm no stranger to electronics, I'd just like this truck to be carbureted and have as few sensors and little wiring as possible. That being said, there's a local guy selling 3 Z24s on Craigslist along with a number of both auto and 5spd trannys. 2 of the Zs are carbed and one is a Z24i. My questions are these: Are these decent engines? Will they fit easily under the hood? Will I have to do a lot of fab work? Is it worth it?

[wayno]

You can get it in there, but it's not going to be easy, the 520 engine compartment is the same as a 320 engine compartment, small.

First thing you will notice after the engine is in there is the heater hoses, the Z24 will be almost touching the firewall and the hoses are in back of the head although the Z24 tilts towards the driver side, so that will be difficult, but it can be done as I have done it, and it is best to do the heater hose mods when the engine is not in the engine compartment.

Next issue is the radiator fan, I like keeping stock fans myself, I will go to extremes to keep them as they do not fail, electric fans do fail.

You will also need to figure out the radiator, I use stock 521 L16 radiators, but I have used a J13 radiator to cool my SD25 diesel engine and it did fine, but I eventually changed over to a 3 core L16 radiator with the radiator hose fittings relocated, I have used this exact radiator to cool a 1970 Datsun 521 with a Z24 in it I built and then sold as I was not impressed with the Z24, my LZ23 would kick that Z24s ass on any given day, but maybe the new Weber on it was not tuned properly.

It can be done, but it is not going to be easy, easy would be to find a J15 out of a forklift and install that, you can use MGB SU packages on it for performance and you can get parts, you also can possibly get parts for your J13 engine at forklift places also. 

[datzenmike]

If you get the KA24E or KA24DE from a D-21 Hardbody (should be lots of those around) you can remove the EFI and make an adapter plate for a weber carb and fit an L series distributor.

 

Story starts around here.... http://community.ratsun.net/topic/3811-my-77-kc-620/page-19

 

 

[Rjawm]

I just can't see why anyone would want to purposefully install a Z24 into anything. 

 

They are not known for their high performance capabilities, without throwing gobs of money at it, although when maintained correctly they will go forever.

 

If going through the trouble to cram/fit a bigger motor into your vehicle it just seems more prudent to go with the newer, more supported, more powerful, more reliable choice.  I get the possible aversion some have to going EFI but as Mike posted above, that's fixable too. 

 

I would suggest not bothering with the Z24 at all, but that's only my opinion and you are free to do as you wish with your own truck :thumbup:

[datzenmike]

Torque is over 130 at  2,800. That 's way over 30% more than any L series 4 cylinder, closer to KA torque. Problem is when the revs get above 4K and looks like it's going to get interesting, uhhhhh it doesn't. If going with a Z24, first loose that 4.875 differential, it's way too short for all the torque you have. Try a 4.11 or lower like a 3.889.

 

A KA will give you slightly more torque but way more out and out HP to 5,500, and beyond capability.

[Lockleaf]

I play with z engines often. I have a z22 swapped in to my 510 and a z24 powered 720. That being said, i would agree with the above. For how hard it will be to shoehorn in there, i would go a different route.

 

I think the j15 would be a great option. They were used in tons of forklifts so parts are still fairly common. And i believe it bolts right to your transmission.

 

2nd to that, the carb conversion on a throttle body injected ka from a d21 Hardbody truck would be next best in my opinion.

[MrGable82]

Any good diesels to look for?

[MrGable82]

So aside from a dreamy turbo-diesel, which KA should I search for? I know they made some with individual main caps and others with girdles. Some with L-series type distributors and oil pumps and some without. Am I correct in saying that the early 240sx had a girdled block coupled with the dogleg 5spd?

[wayno]

Putting a Nissan SD22 diesel in a 520 has been done, but again a lot of work, here is a link to that build.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&cad=rja&uact=8&ved=0ahUKEwj4qK3npqnSAhUN8mMKHUcEAdkQFgg-MAg&url=http%3A%2F%2Fcommunity.ratsun.net%2Ftopic%2F21772-1968-datsun-520-sd22-diesel-build%2F&usg=AFQjCNFFeJyk0r4sC1-UZRPxgWW1OBTRSA&sig2=g6cmpAaR5rf4EUWnwbQxqA

If you cannot find parts to rebuild your J block at a forklift place, I would look into the B210/210 A14/A15 blocks, they made a shitload of them engines and I believe parts will be around for a long time, but you have to fabricate everything to put one of them in a 520.

[Lockleaf]

So aside from a dreamy turbo-diesel, which KA should I search for? I know they made some with individual main caps and others with girdles. Some with L-series type distributors and oil pumps and some without. Am I correct in saying that the early 240sx had a girdled block coupled with the dogleg 5spd?

You want to get a d21 Hardbody truck ka.

 

And no, all 240sx have 71c style transmissions which have reverse below 5th. But yes 240sx are girdled main bearing caps.

[MrGable82]

Is there any advantage to having a girdled block strength-wise? Will it affect clearance?

[datzenmike]

Avoid the 240sx KA engines. The girdle is in the way of modifying the oil pan and the block is larger and including the girdle, is much heavier.

 

The dogleg 5 speed was only used on the first gen S10 200sx '77-'80. It would never survive a KA engine, ever.

[MrGable82]

Ok. So a KA24E with matching 5spd is ideal. Anyone ever turboed one?

[Lockleaf]

Yes. Often. Very often.

 

Ka-t.org is dedicated to turbo ka24 engines.

 

Yes the girdle block is stronger. But to use it will require SIGNIFICANT additional work that likely will be of little overall benefit.

 

Just go 2wd truck ka24 and trans.

[wayno]

I think before you buy anything, you need to start measuring, a L20b barely fits front to back in the engine compartment, how long are KA24 blocks?

[datzenmike]

It's a good question. L,Z and KA cylinder spacings are the same. L and Z timing covers are much the same but for the bolt patterns on the valve cover front and a KA heads will bolt up to a Z series timing covers.

 

 

I'd be more interested in the width.