'70 Datsun 521 Build Farm to Street Edition

[datzenmike]

The A87 head comes in two combustion chamber sizes, both larger than the stock L16 so both will lower the compression.

[Carl Handratty]

1 minute ago, datzenmike said:

The A87 head comes in two combustion chamber sizes, both larger than the stock L16 so both will lower the compression.

 

Know anything about the rusted headers that are on the engine? Were those a OEM or aftermarket option? Maybe just made by the previous owner.

 

[datzenmike]

After market. The L16s came with a cast iron header. Which was easily as good and never wore out.

 

[Carl Handratty]

Need to post on the parts wanted and see if any one has a 99002.825 Datsun L Series Weber Downdraft Manifold available? I'd love to run one on this engine. I think I wanna try my hand at EFI like a few others on the site and this seems to be a good option for the flange attachment and just overall air performance. Top End Performance says they're backordered everywhere because of a foundry issue. 

[datzenmike]

Pretty sure they are no longer made, there's not much of a market. Besides there's no real world performance gain. The outer runners are different length than the middle two, unlike the stock manifold. I would spend the money saved on an EI distributor. 

[Carl Handratty]

16 minutes ago, datzenmike said:

Pretty sure they are no longer made, there's not much of a market. Besides there's no real world performance gain. The outer runners are different length than the middle two, unlike the stock manifold. I would spend the money saved on an EI distributor. 

Noted! I am tryna squeeze every horse outa this thing. My other cars have v8s so this is a completely different territory for me and when i get it on the road I don’t wanna be sad. Ha. I won’t no matter what but you know what I mean. 
 

any other performance upgrades you suggest? Cam and lifters?

[datzenmike]

That header is fine... till it leaks and wears out. When it does I would revert back to stock cast iron header for reliability. 

 

 

 

32/36 is a good start but I don't think the intake will matter. Nissan would have easily designed it this way if it made any difference.

 

An EI (electronic distributor) and matching coil from a '79 or '80 L20B. More reliable, higher output and never have to replace or set points again.

 

Replace all the exhaust after the manifold with larger diameter and a quieter turbo muffler, not a 'see through'. What's the 521? 1.75"?? pipe diameter? Go to 2". A 2 inch pipe has a cross sectional area that is 3.14 square inches. The 1.75 pipe is only 2.4 square inches. That's 30% bigger area which will come in handy for moving increased exhaust from a possible cam change.

 

Have your cam reground with a bit more lift but don't go overboard on the duration. A cam change will move the power higher in the rev range leaving the lower end deficient. This is where you drive most of the time and not above 5k. Try to maximize mid range torque. 

 

Best bang for the buck would be an L20B swap giving you about 20 hp and torque from the displacement increase. Getting 20 more HP from an L16 won't be cheap and like I said it's at RPMs you don't drive at. Torque is what pushes you back in the seat.  Better yet a rebuilt Z22 block with L20B head and manifolds. That's a 37.5% displacement increase and well over 100 hp and more as the compression will also increase. Good thing the exhaust diameter was increased.

 

Switch to electric fan and ditch the power robbing mechanical one. Each fraction of a HP saved adds up.

 

Electric fuel pump for the same reason.

 

Make a cold air intake for the Weber. Ambient air from in front of the radiator is denser and will mix with more fuel for more power than ht thinner air. Also reduces pre ignition. 

 

 

[Carl Handratty]

3 hours ago, datzenmike said:

That header is fine... till it leaks and wears out. When it does I would revert back to stock cast iron header for reliability. 

 

 

 

32/36 is a good start but I don't think the intake will matter. Nissan would have easily designed it this way if it made any difference.

 

An EI (electronic distributor) and matching coil from a '79 or '80 L20B. More reliable, higher output and never have to replace or set points again.

 

Replace all the exhaust after the manifold with larger diameter and a quieter turbo muffler, not a 'see through'. What's the 521? 1.75"?? pipe diameter? Go to 2". A 2 inch pipe has a cross sectional area that is 3.14 square inches. The 1.75 pipe is only 2.4 square inches. That's 30% bigger area which will come in handy for moving increased exhaust from a possible cam change.

 

Have your cam reground with a bit more lift but don't go overboard on the duration. A cam change will move the power higher in the rev range leaving the lower end deficient. This is where you drive most of the time and not above 5k. Try to maximize mid range torque. 

 

Best bang for the buck would be an L20B swap giving you about 20 hp and torque from the displacement increase. Getting 20 more HP from an L16 won't be cheap and like I said it's at RPMs you don't drive at. Torque is what pushes you back in the seat.  Better yet a rebuilt Z22 block with L20B head and manifolds. That's a 37.5% displacement increase and well over 100 hp and more as the compression will also increase. Good thing the exhaust diameter was increased.

 

Switch to electric fan and ditch the power robbing mechanical one. Each fraction of a HP saved adds up.

 

Electric fuel pump for the same reason.

 

Make a cold air intake for the Weber. Ambient air from in front of the radiator is denser and will mix with more fuel for more power than ht thinner air. Also reduces pre ignition. 

 

 

Thanks for the good insight. I really appreciate it. Yeah, my header already has a pitting hole in it so I'll probably junk it. It's in rough shape. I'll keep an eye out for a stock exhaust manifold. My tailpipe is missing from the header on out so on the next rendition I'll get a 2"er in there. 

Now you got me thinking about trying to find a L20B. There's a few L28s in my area but that's about it. Harder to find now I guess. I'ma look into that Z22 block though. I may have to just go KA by necessity. Few DE's floating around the area.

Yeah I always run e fans. Was planning on removing the fuel tank and running a cell where the spare hangs and use a block off plate on the original pump location.

 

Before all this, I guess I should be focused on suspension parts likes bushings and whatnot because I'm doing a body off restoration. I have a good powder coater in town who can do the frame. I'll need to find all those kingpin parts and bushings once that's complete.

[banzai510(hainz)]

that motor has a diffent fuel pump that standard 510/521/

Is this a L16 maybe a different motor installed?

wheels look good.

 

I would have filled the bed with nice soil an make a planter box of of the truck in front of house.(Ok just joking)

[Carl Handratty]

1 minute ago, banzai510(hainz) said:

that motor has a diffent fuel pump that standard 510/521/

Is this a L16 maybe a different motor installed?

wheels look good.

 

I would have filled the bed with nice soil an make a planter box of of the truck in front of house.(Ok just joking)

Dang! Opportunity missed to have a rolling garden bed! Still time I guess! Can you imagine some 8' sweet corns in a perfect row back there? Haha perfect Midwest build.

You know with the l87 head and the exhaust header, I'm wondering if they did some work on this thing at some point. It is a L16 on the tag by the dippy.

[banzai510(hainz)]

Sun Flowers!!!!!!!!!

[Carl Handratty]

Some nice snowy pics of the Dats. Can see I got the flower bed shoveled out of the back. Only a couple pin holes near the passenger wheel well. I was really happy to see how solid the metal was.

 

[datzenmike]

I see you have the deluxe emergency brake there. I use...

 

[datzenmike]

When you pull the head, it may need work or replacement, that's the time to lift the header out and weld it up. Sand blast it and spray with header or high temperature paint to get a few more years out of it. 

 

[Carl Handratty]

Anybody used these Redux Garage guys outa Canada? I mean what more could you ask for. Nice looking panels. I need rockers, driver front floor and firewall. Tryna decide if I just buy them all and replace everything. new new new. But...at a cost.
https://reduxgarage.com/collections/datsun-520-521

[banzai510(hainz)]

thanks for the link I didnt know poepl made them for 521s

[bilzbobaggins]

I think this is the fellow I ordered  mine from.  Dude was from edmonton.  

[Crashtd420]

23 hours ago, Carl Handratty said:

Anybody used these Redux Garage guys outa Canada? I mean what more could you ask for. Nice looking panels. I need rockers, driver front floor and firewall. Tryna decide if I just buy them all and replace everything. new new new. But...at a cost.
https://reduxgarage.com/collections/datsun-520-521

Well worth it if your floors are bad enough.... other wise replace the areas needed... the factory metal is pretty solid if it's not rotted out... stab at the floor with a screw driver, if solid coat with some rust preventative and you'll be good....