l20b + 5 speed in a pl521?

[datzenmike]

use your l16 oil pan and you'll be fine. i put my l20b in and didn't have to do any tranny stuff. directly bolted in. 5 speed is a whole different story.

 

I did this in the '70s. L20B dropped right it. Don't remember changing the pan but must have as the L20B was from a car. This would explain why I had no trouble with the stock throw out bearing as the car L20Bs used the same 200mm clutch as the 521. Dumb, blind luck as I knew very little about Datzooons back then.

[fisch]

so how did it come out

i have a 521 1971 truck and im puttin in a l20 and im wonderin if it will fit with my 4 speed xD

i wanna know how urs came out?

 

Wowzers this is an old thread! And what's more sad is I still haven't done any swap, but I do have an l-18 that is on the stand, so I guess I got a little closer.

 

SDsurf and hessianben's threads are filled with awesome info. But SD pretty much spelled it out for you in his reply. Everything you need to know.

 

But yes, if you are keeping the stock 4speed it is even easier because you don't have to shorten your trans mount 2 inches as you would have to for the later transmissions. And you don't have to mess with your driveshaft.

 

Good luck!

[kezark31]

i have an l20b with the matchbox dizzy and a four speed in 72 521, with 3.88 gears (thanks jester for the gears). and i really wish i had a 5 speed. With 26" tire and 4spd @2500rpms im rollin at 49 mph per the garmin gps. truck is real quick light to light but any hwy driving sux. i dont dare take it on the freeway.

[whitechef]

You probably ought to get them both. You can't have to many L parts laying around,

Very interesting stuff guys. Thanks!

 

The seller mentioned he might still have the rear end from this 78. I wonder if he has the 2 piece driveshaft too.

 

As for crossmember modification, if he has the original, are we talking drilling a few new mounting holes and using some grade 8 bolts, or actual cutting and welding?

 

As I mentioned in an earlier thread, I may have to have my engine pullled to replace the main seal. If that is the case i wondered if I should swap something functioning in there rather than repairing what I have (96K on this motor).

 

There are two engines around me. i had been adopting a 'wait and see' attitude with my current motor/trans- but both of the sellers are talking about scraping these if I don't get them soon. And as you might guess, even l16 are rare the north east. In fact in a year of looking I've only ever seen 3 L-series 4 banger motors for sale in a tri state area.

 

1) $350 gets me the above l20b + 5speed (and possibly the rear end) with everything but the radiator. 78000 mi on it. (+ a three hour drive to get it, one way.)

 

2) $100 gets me a working L16 + 4 speed and everything, Including a rebuilt hitachi carb (not that i need it w/ my weber) and an extra questionable 4 speed. (1 Hour drive one way)

 

 

What would y'all do?

[DanielC]

I have a PL521, that I put a 5 speed into, and later swapped a l-18 into.

For the five speed swap, I used a new Z car "rally" transmission. it was the lowest first gear five speed I could find, and I was making good enough money to be able to buy a new one from the dealer.

Clutch

I had no issues with the clutch, throwout bearings, or bolting the 5 speed to the engine. I used a Z-car slave cylinder to match the transmission. I think a bit of luck was involved here.

Mounting

The rear of the transmission sits on and bolts to a mount that bolts to the frame crossmember with 4 bolts. I removed it, and shortened it to match the mount on the five speed.

Shifter location.

The shifter was farther back. I removed the plate, and cut a hole farther back, and used the metal I cut out of the new hole to patch the old hole.

Driveshaft

I got a slip yolk that matched the transmission. I had the driveshaft shortened to match the distance from the carrier bearing to the transmission.

Almost any medium or larger sized city should had a driveline repair shop that can shorten and balance a drive line. You should give them both parts of the driveline to balance it.

Speedometer

You need the longer cable. I believe my truck has a Z-car cable in it. I do not recall the exact one. You may need to get the speedometer pinion out of your old transmission to make the speedometer read correctly. Mine does not.

Electrical

You may need to make short extensions for the reverse lamp switch. The PL521 also has a third gear switch, and a neutral switch on the 4 speed transmission. My third and neutral switches are not currently hooked up. These two switches are used with the dual point distributer.

Additional items

If you can get a clutch plate for a 2000 roadser, it will bolt up to a 200 mm flywheel, and increase your clutch holding power a lot. Your left leg will get stronger. If you have a bench seat in your PL521, itis way easier to remove and replace either transmission with the bench seat out of the truck.

Edited November 7, 2009 by DanielC

[hessianben]

make sure you use a l20b oil pan from a truck. a car oil pan wont fit. so if your donor engine came out of a car you will need to source a oil pan to swap. the sump is 2 inches more forward in a car (same bolt pattern though) so you wont even be able to get it in. if you dont know what your donor engine came from then its time to break out the tape meaure. we'll cross that bridge when it comes bro. peace

 

1. the L20b is a direct drop in for sure! use the 521 mounts. (right Mike/SDSURF? LOL) I tried using the L20 mounts from a 620 and it did not work.

2. any L series trans will work, but some are longer and require the tranny mount to be shortened.

3. depending on which trans you run, the driveshaft may need to be shortened.

(I was able to modify my driveshaft and pair it with the donor driveshaft with no welding)

4. if you have the option, get the rear end with the 5 speed. My stock 521 rear is geared pretty short for the 5 speed i have paired to it.

5. each throwout bearing is paired to the clutch it comes with, not necessarily the vehicle.

6. use the oilpan and pickup from the 521- even the 620 pan doesn't fit past the 521 front xmember.

 

 

regardless of which motor you choose, you'll have a blast tearing it down and rebuilding it! Don't assume it's good- doesn't cost much to do it properly, and you will be much happier with a cleaned and dialed motor!

(and I know you want to start painting too :D)

if I had to do it again, I would rebuild the bottom end as well- I assumed mine was good, and now I've found I'm burning oil... do the rings.

 

here's my thread:

http://forum.ratsun.net/showthread.php?t=15075

 

search for copacetickid's thread- he did a full rebuild with pretty good pics and instructions.

 

do it! you're stoked!

[sdsurf]

ben has it right on! there is also info on the 5spd swap in FAQ from pac coast

 

1. the L20b is a direct drop in for sure! use the 521 mounts. (right Mike/SDSURF? LOL) I tried using the L20 mounts from a 620 and it did not work.

2. any L series trans will work, but some are longer and require the tranny mount to be shortened.

3. depending on which trans you run, the driveshaft may need to be shortened.

(I was able to modify my driveshaft and pair it with the donor driveshaft with no welding)

4. if you have the option, get the rear end with the 5 speed. My stock 521 rear is geared pretty short for the 5 speed i have paired to it.

5. each throwout bearing is paired to the clutch it comes with, not necessarily the vehicle.

6. use the oilpan and pickup from the 521- even the 620 pan doesn't fit past the 521 front xmember.

 

 

regardless of which motor you choose, you'll have a blast tearing it down and rebuilding it! Don't assume it's good- doesn't cost much to do it properly, and you will be much happier with a cleaned and dialed motor!

(and I know you want to start painting too :D)

if I had to do it again, I would rebuild the bottom end as well- I assumed mine was good, and now I've found I'm burning oil... do the rings.

 

here's my thread:

http://forum.ratsun.net/showthread.php?t=15075

 

search for copacetickid's thread- he did a full rebuild with pretty good pics and instructions.

 

do it! you're stoked!