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L20b 86mm pistons


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#81 Kingcab

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Posted 08 January 2018 - 04:16 PM

Yes 100 percent correct. I just picked the welder up I'm going to be welding the diff here shortly

#82 datzenmike

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Posted 08 January 2018 - 05:34 PM

Anyone know if the 300$ Lincoln stick welder 225 amp is any good from home depot? Ac current..... for welding my diff

 

Welded diff.... AKA a Lincoln Locker

 

You won't need a LSD or a welded diff with an L20B. Open diff is safer to drive. But, oh well. Expect constant slight under steer (ploughing ahead into corners) and the odd sudden unexpected over steer on corners. Stay alert..... and lots of tire wear.


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#83 wayno

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Posted 08 January 2018 - 06:42 PM

I have an LSD in my turbodiesel 521 kingcab and I don't like it, the back of my truck isn't heavy enough and it keeps getting a mind of its own going around corners/making a left turn when it is wet/raining outside and I give it some pedal, it is getting old.


 

 


#84 datzenmike

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Posted 08 January 2018 - 07:06 PM

The outer rear wheel has to go farther than the inside wheel on a corner. The tighter the corner the more the difference. With a welded diff the tires are forced to turn the same speed so one or both are sliding some amount and to add to this the shifting body weight will bear down more on the outside wheel forcing the inner wheel to speed up and slip shifting the vehicle to the outside even more. An LSD will allow the wheels to turn at different speeds because traction overcomes the built in clutches and they do the slipping, on dry pavement that is, and if the clutches have a moderate break away setting. Poor traction like mud, snow, wet changes this also. LSDs and welded diffs are great in poor traction and straight away acceleration. On a sloped surface they tend to over steer to the down hill side. Once you lose traction it's very hard to get it back.

 

Ever watch those U tubes where muscle cars are leaving a show and they light the tires and get out of shape and swerve back and forth and then hit something or go off the road, and you say to yourself... fuck what an idiot, I could have done better steering that car??? Well that is almost certainly an LSD that adds unpredictable over steer to those who are not used to it, or thought they were used to it. 


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#85 Kingcab

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Posted 09 January 2018 - 12:45 AM

I've done more than enough research about welded diffs. It's a drift truck anyway not to woried about tires. And yeah it will defenatley take some getting use to let's hope I don't unexpectedly loose control. What rear end oil should I use.. i think I have some 85 150 or something like that laying around if that will work?..

#86 datzenmike

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Posted 09 January 2018 - 05:53 AM

Stock 90W is fine. 150 would be better for severe heat which Oregon isn't. Too thick isn't good when very cold either. I've used a synthetic blend and... it leaked past the pinion seal and make a damn mess. Switched back and it dried up. 


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#87 Kingcab

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Posted 09 January 2018 - 11:24 PM

Anyone know where i can get a new timing chain front cover?? With waterpump??

#88 wayno

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Posted 09 January 2018 - 11:40 PM

There is a 2wd 1980 Datsun 720 with an L20b engine at the Sherwood OR pick and pull, it still had the engine with the front cover/water pump on it, I was there today getting the oil pan, starter, bypass coolant piping, and fuel piping.

The transmission was gone, the radiator and shroud were still there also, it had brand new non-vented rotors(drilled type).


 

 


#89 Kingcab

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Posted 09 January 2018 - 11:59 PM

That 3 hour drive from me all I habe is the datsun for transportation haha. Was wondering if there was any company that made bran new ones. Otherwise I'll just look at local junk yards

#90 wayno

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Posted 10 January 2018 - 12:19 AM

The local yards is your best avenue, any L20b will work(620/720).

It's actually almost and 2 hour drive for me round trip if traffic is normal, it sucked today, I seriously believe all them people are crazy/loony for going thru that bullshit 5 days a week, there were no wrecks, so why was it stop and go for 15 miles, they are loony, I am not going back there for a while, I had my dose of loony today, I am good for a month at least.


 

 


#91 Kingcab

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Posted 10 January 2018 - 07:56 PM

Is it possible to resurface the timing cover??

#92 datzenmike

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Posted 10 January 2018 - 08:00 PM

A very mild re-surface I don't see why not. Pull the two tiny alignment dowels out. Replace the front seal. Bolt holes should be large enough for the oil pan and head.


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#93 wayno

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Posted 10 January 2018 - 08:59 PM

Why would that part ever need to be resurfaced?


 

 


#94 flatcat19

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Posted 10 January 2018 - 09:53 PM

Scrub it clean with some scotch Brite pads and call it a day.

You can't hang if your nuts haven't dropped...it's physics


#95 Kingcab

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Posted 11 January 2018 - 02:04 AM

You all have been so helpful with my build and issues during it all! I can't thank you enough!! I'm thinking about cutting about 2 feet off the rear end of the bed and rewelding the tailgate and hinge section back on has this ever been done do you know?

#96 Kingcab

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Posted 11 January 2018 - 02:07 AM

And the reason for me wanting to resurface the timing cover is that the head was resurfaced due to over heating and I believe the timing cover is also aluminum and it has always dumped oil out no matter how much gasket seal I use

#97 datzenmike

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Posted 11 January 2018 - 05:50 AM

You all have been so helpful with my build and issues during it all! I can't thank you enough!! I'm thinking about cutting about 2 feet off the rear end of the bed and rewelding the tailgate and hinge section back on has this ever been done do you know?

 

It's called 'bobbing'. I don't know about 2 feet. There has to be frame for the leaf springs to mount to. I've seen the frame, driveshaft and box shortened in front of the rear wheels and everything moved forward. Gas tank is a problem but one could be mounted where the spare is. 

 

 

And the reason for me wanting to resurface the timing cover is that the head was resurfaced due to over heating and I believe the timing cover is also aluminum and it has always dumped oil out no matter how much gasket seal I use

 

Get several sheets of #200 sand paper and tape to a glass table top. Slide the timing cover gently back and forth on it. If there are low spots it will show. There's no reason for it to leak unless damaged and it couldn't have been damaged if it was on the engine. New gaskets will fix this.


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#98 Kingcab

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Posted 16 January 2018 - 12:46 AM

Sooo just a thought... for later down the road... whay would I need for a supercharge kit for my l20b full list would be ausome so I d'can slowly buy parts

#99 datzenmike

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Posted 16 January 2018 - 05:50 AM

A supercharger.... maybe from an Xterra? Larger carb? The rest would be custom made one off parts. Intake, mount for SC, belts and pulley.


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#100 Lockleaf

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Posted 16 January 2018 - 10:02 PM

Basically what Mike said. There isn't a kit. You will be custom building it. You will need to understand blow through vs suck through supercharging so you can decide which you want to deal with.

Start by looking at kits made for other 4cylinder engines, like the TRD kits for scions or aftermarket kits for Hondas and Subarus. You could also look up KA24DER builds.

Half Pint ('71 510 Goon) http://community.rat...agon/p?=1269361

 

Audrey ('69 Roadster 1600) http://community.rat...rey-the-ratster

 

Tiny Havok ('85 720 DIY built Crewcab 4x4) http://community.rat...ache/?p=1395455

 

720 Shenanigans http://community.rat...20-shenanigans/