Radiator options

[1979_datsun_620]

Hey guys I'm almost done with my KA24DE swap.

I've tried researching what radiator would work best on my 620, but found no luck.

Any suggestions on which radiator would work best?

[datzenmike]

The 620 did come in three core and of course they fit perfectly but the inlet is over on the left side. I tried fitting an '81-'82 Z22 rad, which has the inlet on the right. It's slightly taller and much wider and would not fit between the high beams so that was out.

 

A shop could refit your 2 core with a three core.

[1979_datsun_620]

Oh I see.... I don't have my radiator from my 79 620.

I was trying to just purchase one that would require minimal fabrication other than the brackets. 

[datzenmike]

Places like Summit Racing ? have replacement aluminum rads. I would get the one for the 620 and just use a couple of elbows to join the top rad hose over to the left side. https://www.summitracing.com/int/parts/sgt-cu638/overview/year/1979/make/nissan/model/620

 

[Dolomite]

Look on ebay, champion has all kinds of radiators for swapped vehicles. I have a regular 510 model, it works well, especially for $200. Not sure if they have one specific for a ka 620 though. They’re three row, polished aluminum, supposedly good for 400hp.

[racerx]

Koyo is the best. See if they have yours. Pricey but better than others.

[Moist Lightning]

Also early 620 had rad inlet on right side. 

[datzenmike]

They did but for an L16. The L20B was larger and why the rad support us bowed outward for more clearance...

 

 

[Moist Lightning]

They did but for an L16. The L20B was larger and why the rad support us bowed outward for more clearance...

 

 

 

Never notice that, thanks. Just got a late model recently too. surprising amount of small differences.

[FrankRizzo]

I thought the rad support bowed on '75 and onwards to make room for the A/C condenser?

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[datzenmike]

A/C was a '79 factory option on the 620 using a York compressor bolted to the head where the fuel pump would be and an electric pump used, though the dealerships might install them on earlier models with the compressor under the distributor. The dealer installed ones do look sort of 'rigged up' with hoses looped around the back side of the engine. The L16/18 didn't use a clutch fan but the L20B did for sure and needed extra room forward.

[FrankRizzo]

^ that makes sense.

 

OP, look at a '79-82 Mazda RX-7 Rad. Someone here installed one and the hoses are on the correct side and the size is close.

 

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[Seeker > 620 KC]

I bought a 3 row, all metal from O'Rileys 3-4 years ago.

 

As I recall from my Datsun dealer AC installation days... the 620 Nissan brand condensers always mounted behind the grill, and in front of the Rad Core support.   

[FrankRizzo]

The more I think about it - - - Mikey's explanation makes perfect sense.

The rad support bows in (away from the engine) after '75 to accommodate the larger (longer) L20.

 

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[datzenmike]

L16/18/20B are all the same length. The L20B is 2cm (3/4") taller than the L16/18.

 

The L20B rad might be slightly wider (don't know) but with extra space forward you can add a third row of tubes and fins making it a least 1/3 larger capacity.

[1979_datsun_620]

I ended up using a stock 1979 620 radiator. Works fine!.... so far....

[datzenmike]

Sure, it might get hot if the hill was long enough but will be fine for everything else.

[Soundline]

To avoid redundancy in threads, are there any additional modifications needed for a 74’ 620? My rad is leaking... again... and I’m looking to replace it for a L20B that’s already installed.

[datzenmike]

Post #8 shows the '74 and older have less room for a thicker rad. I think that L20Bs with the clutch fan stick out farther so a later L20B rad may be a tight fit in a '74. After market might be better.

[Moist Lightning]

To avoid redundancy in threads, are there any additional modifications needed for a 74’ 620? My rad is leaking... again... and I’m looking to replace it for a L20B that’s already installed.

 

 

Post #8 shows the '74 and older have less room for a thicker rad. I think that L20Bs with the clutch fan stick out farther so a later L20B rad may be a tight fit in a '74. After market might be better.

 

My 73 came with a l20b & clutch fan. Fit fine with the l16 rad, seemed to cool fine too. However, it doesn't get super hot where I live.

[datzenmike]

Good to know. Yeah Canada is only ice free through July and August.

[G-Duax]

That is about the same for Texas, it only stays below 80 from January & February.

I think we only got below freezing for 2-3 days this year, and that was only at night....

 

I've been running a VW Sirocco radiator, and it works, almost. 

Sometimes I have to run with the heater on, and if stuck in traffic, I just shut the engine off.

[Soundline]

Thanks, it gets hot as **** here, so I’ll look at aftermarket options.

[Soundline]

Fuck it... I am having it recored. If it’s done on time it’ll be at Canby. I was given one out of a newer model which is also being recored as a spare.

[distributorguy]

I'll take a recored original over any aluminum option any day of the week.  If they put a newer style Modine core in it, it'll cool better than it ever could have new.   :thumbup: