I am building a Crawler out of a 73 Datsun 620 its fully caged with motor and trans in... about to start the fun part the susp. im usin 12 bolt rear and dana 44 front axles I was thinkin about buggy leaf rear...basicly im just askin for a heads up on any problems that i might run into or and any tips i can get. Im tryin to have it finished and crawlin 4th of july weekend here are some quick stats...

1973 datsun 620 (est. weight 3200lbs)
Chevy 350 with about 400hp 350lbs tq.
trans and transfer is out of a 78 gmc 1/2ton with granny low
leaf spring (buggy leaf?")
(stock lengh)12bolt rearend and dana44 front with 3.73 ratio with
im building the truck for a 38" tire

i still need shocks,drive shafts,rear locker and a few nik-naks any sugestions?

On the 12 bolt, put a Detroit in it.

Driveshafts will have to be measured once you get it all together, but will most likely need to be custom for the right length.

A coilover setup all around would be cool, but expensive. You could just use a standard leaf setup out back with some really long leaves for maximum flex. Would be more stable for road driving that way, or will this be a trailer queen?

Would love to see pics. 620s are cool.

pics are on the way...im gunna run chevy leafs for right now(is the longer?)...but whats the word on buggy leaf? do or dont?

Leaf springs don't flex


What exactly is a "buggy leaf" anyways?

you might be referring to the quarter-elliptical leaves... ?

a buggy leaf is similar to a 3/4 elliptic, except the upper half spring is only a single leaf, not a whole pack.

picture a 1/4 eliptic, using the spring eye as the shackle mount for a normal leaf spring underneath. thats 3/4 elliptic.

A buggy leaf setup is just having the half pack as 1 leaf. It means the leaf lays flat against the frame in any kind of compression situation, then pulls off the frame for droop. Just another way of getting lots of droop from a leaf spring setup.

thats the way i understood it.....good or bad? an whats 1/4 eliptic? never heard of it....

buggy leaf isn't bad, fallen out of favor perhaps. It just gives a lot of droop, but it seems that drooping a tire 2' doesn't do anything for you when theres no weight on the tire anyway. You might as well leave it in the air.

As far as quarter elliptic.... well, here goes an attempt at an explanation.

Start by fabricating a 3 link or 4 link suspension. quarter elliptic is (usually) for springing the axle only, not locating the axle.
Cut a regular leaf spring in half.
Bolt what used to be the middle of the leaf spring to the frame, then use a shackle of some type to attach the leaf eye to the axle.

Yes, 1/4 elliptic just replaces the coil or coilover with a custom 1/2 leaf pack. The rest of the 4-link is still there.

It does require a HUGE spring pack, usually 12-14 leafs to hold the truck up.

So, you're building something that in no way could be called a 620, much less a Datsun, anymore?

quote:

Originally posted by OffroadX:
So, you're building something that in no way could be called a 620, much less a Datsun, anymore?

Well, yeah....because we all know what an awesome wheeling engine that L20 would be. Man, talk about big HP and gobs of low end torque....

Last I knew, there aren't any OEM 620's running around with a Tcase either.

I think it's a cool project.

quote:

Originally posted by Desert Rat:
I think it's a cool project.

I think it'd be even cooler with some pics

quote:

Originally posted by OffroadX:
So, you're building something that in no way could be called a 620, much less a Datsun, anymore?

the only thing left to call a datsun is the skin and about 1/3 of the floor pan LOL
sorry on the pics guys ill have a few by saturday garented just havent found the time to go around and borrow one i think a friend of mine as some pics from when i first started it if so ill post those this week

quote:

Originally posted by OffroadX:
So, you're building something that in no way could be called a 620, much less a Datsun, anymore?

I'll call it a 620. Hell I may even call it an ExTerra just to get under your skin.
Lator...

heres the deal on the motor...i got the truck with no motor always wanted to crawl a 620 just because you dont ever see them on the trail and since i already had axles and trans/transfer behind my shop and since normally and a dirt slingin red neck at local dirt tracks and have a few(4) spare motors ready to go the on i chose for the "SickPig :smiley: " is steel crank,billet main caps,6.125 corilla rods,4.060 12.5 J&E pistons,schubeck ceramic lifters, edelbrock 485 lift 250 dur. cam, manley 1 piece push rods, Dart platnum 64cc 7/16screw in studs girdles and guild plates,1.7 roller rockers,stainless 205int. 160exh. valves, holly Contender intake I just used desktop dyno and with my parts it said 465hp 385tq. witch is 1:6.9 power to weight ratio...a mustng 5.0 is a wopping 1:12.8 lol AND my datsun has 1/2 in. shorter wheel base HAHA i love it

d44/12bolt combo, 35's like you've said in another thread... you'll never get to use all that motor. not even close.

i know gear like in all motorsports is the key but im just buildin a play toy that as i get new stuff or breake the old it will be upgraded its just so happends i started with all the motor i will ever need my plans are to ditch the 1/2ton axle for 3/4 or 1ton axles and when i do they will both have lockers gears and the whole nine yards

quote:

Originally posted by OffroadX:
So, you're building something that in no way could be called a 620, much less a Datsun, anymore?

I'd say close to 90% of seriously built rigs out there aren't much more oem than the body, if they even still have that...

oh and btw... haha

ok guys ive finally heard it enuf times that i am borring a camera as i post this and will have pic uploaded by tomaro...and then finnally this post will be worth a penny or two