Driver 521

[Master-O-Turbonics]

So I bought a couple 521's a little over a year ago, on the same day in very different parts of Georgia. 521's are super rare here so I had to snatch them up. Ended up selling the truck in the back so I just have the one in the front and of course the Rock crawler that I'll never finish.

 

 

 

 

Plan is to get this thing up and running/driving as cheaply as possible (Ratsun style) but making the truck better.

Plans:

L20B/weber swap (in possession)

Stubby 720 4x4 71B transmission(needs final assembly)

720 fuel tank(in good shape)

Go through the brakes ($225 on Rock Auto)

Rewire headlights/horn/brakelights

Install my freshened 521 bench seat

Stop the rust/repair what is really bad (bottom of doors and under headlights)

Some sort of radio/speakers whatever is cheap/free

 

 

I purchased a L20B that was mounted in a 510 that came out of a buddies shop for pretty cheap.

 

 

A couple measurements and it looks like a 720 4x4 tank will fit on the right side under the bed, just going to have to get tricky with the exhaust. This will allow close to 28 gallons of fuel with both tanks so it should get around 500 miles on a fill up... If the second tank fits.

 

[wayno]

The 4wd transmission tailshaft doesn't have the speedo drive in it, what are you going to do about the speedo?

You will need to use the L16 oilpan/pick up tube and likely all the L16 mount hardware.

The door looks to have most the rust on the passenger side anyway.

You have the Blues?

[Master-O-Turbonics]

The 4wd transmission tailshaft doesn't have the speedo drive in it, what are you going to do about the speedo?

You will need to use the L16 oilpan/pick up tube and likely all the L16 mount hardware.

The door looks to have most the rust on the passenger side anyway.

You have the Blues?

Not really worried about speedometer. Nobody obeys the speed limits and I highly doubt I'll be going faster than the majority of folks on the road haha.

I planned on stripping the motor to the longblock and freshening up all the gaskets before it goes in the truck when I do the motor swap. The 521 currently has an L16 in it but has not run in a decade. I got it to run a little bit on brake cleaner and a matchbox dizzy but I'll leave that motor as a core/worst case scenario backup.

I definitely have the blues. 3 light blue 1971 521's lol. Now 2 but yeah lol. Plus that corolla I painted back in 2011 lol.

I may swap the Rock crawler doors onto this truck

Since they are much more rust free, although one is kinda dented from some hoodlums.

[wayno]

The L20b is a great engine for the 521 as a daily driver, best upgrade I ever made to a 521, the second best upgrade is a tie between going from a downdraft carb to Dual SUs and going from a L20b to a LZ23, the SUs are awesome, but so is that LZ23.

Put the L20b in it and drive it, next I would put disc brakes on the front if you drive it a lot, if it only gets driven every once in a while the drum brakes work fine.

[flatcat19]

My speedo hasn't worked in years. I use the Ulysses app from my phone. Works great.

[datzenmike]

There were 2wd shortys.

 

 

 

Remove that L20B exhaust manifold and put the L16 4 into two exhaust on instead.

 

Hang onto that 4 speed for a spare. The 521 spline can be easily modded to work with it.  

[Master-O-Turbonics]

There were 2wd shortys.

 

 

 

Remove that L20B exhaust manifold and put the L16 4 into two exhaust on instead.

 

Hang onto that 4 speed for a spare. The 521 spline can be easily modded to work with it.

 

This truck actually has a complete original looking exhaust on it, so I'll swap the L16 manifold since in theory it still bolts up

(will the L16 manifold/y pipe clear the block/trans?)

I have issues keeping extra driveline parts around... Lol finally put my spares/ on a furniture dolly and strapped them together with a ratchet strap.

[datzenmike]

The L series flywheels are the same diameter so the transmissions bells will also be close to the same. So yes i should fit ok.

 

 

 

I see a T-100 and what looks like a 71C with an L series front case, an '80 or newer 71B rear half with an SR? or KA front case, an L series front case on top by itself and the last one is hard....  for a VG engine? FS5R30A???

[Master-O-Turbonics]

The L series flywheels are the same diameter so the transmissions bells will also be close to the same. So yes i should fit ok.

 

 

I see a T-100 and what looks like a 71C with an L series front case, an '80 or newer 71B rear half with an SR? or KA front case, an L series front case on top by itself and the last one is hard.... for a VG engine? FS5R30A???

Pretty much on the money.

I'm worried about the L16 manifold moving upward into the Bellhousing because of the taller deck height on the L20... Maybe it's not a concern.

 

The one you can't see is on the back. L series Bellhousing, trans filled with a 280zx gearset stacked on a stubby 720 4x4 output and tailhousing, and a truck input shaft/drop gear giving a 3.7 first gear and .9 5th gear. Don't remember other ratios but I remember 3-4 is a pretty big RPM drop hopefully it's not too bad once I get it driving.

 

 

The 71c/b bell trans was swapped by someone that didn't clearance the inside of the case or overbore the front housing. Needs taken apart and machined.

The 71b trans is sitting in the ka Bellhousing just for storage lol

The vg trans is out of my 04 frontier because of the 5.3L/NV3500 swap.

[HOGIE]

You will need to use the oil pan that’s on the motor in the truck now. 510 pan will not fit.

[Master-O-Turbonics]

Did things.



Used a 620 oil pan that I had laying around and clean with a gasket already siliconed on to the pan... and it doesn't fit too well. Probably pull the center link on one side and air hammer the pan some.

 

forgot to mention I put the motor in with a 510 trans, so i will go ahead and swap the yoke out from the 4 bolt flange to a regular slip yoke. This should allow the stubby 5 speed swap to just need some trans mount fab work, and the stock driveshaft should fit. 

[flatcat19]

Did you not have a 521 pan sitting around?

[HOGIE]

The L16 that was in the truck I would assume has the correct pan unless it was too air’hammered to use

 

 

Nice job getting work done

[Master-O-Turbonics]

Yes but I had no other pan gaskets and I was itching to get this swap done. So I made it happen. Plus the 620 pan looks to have an good extra bit of oil capacity over the 521 pan. Gasket sealed on both sides with Hondabond, the best silicone sealant there is lol.

[datzenmike]

It may be 'deeper' for the longer throw for the L20B crank. Or there may be more room in a 620 so it's lower but all L 4 cylinder engines have the same amount of oil in them. Fill with 4 qts and look at the level on the dip stick.   

[Master-O-Turbonics]

Tossed a fuel filter and hose on it.

 

Fuel tank looks good.

 

Going to have to do something here I think

[Master-O-Turbonics]

Well I finally got back onto this thing a bit. 

 

 

Cleaned up and painted some 4x4 leafs, ordered some eye bushings that were close enough to 521 front bushings that I could make them work. 

L20B, freshened up 32/36 carb, and going with a late 720 4x4 5 speed trans that is the same length as the 521 trans, just have to swap it to a slip yoke on the driveshaft. also power brakes from a 720 4x4. 

[d.p]

Pics don't work.