Basic LZ22 Build w/ Flat Top SSS SU

[Sealik]

Picking up a pair of SU SSS carbs with a K14 manifold, complete linkage, heat shield, and triangle air cleaners!  Stoked.  Should have them in my possession by tomorrow evening.  Anyways my question is should I break in the engine with the Weber 32/36 since I know it runs well before I slap these carbs on that need to be cleaned and jetted and what not.

 

Also bought a Paraut water pump for $45 dollars.  Not bad.  Got the one for the L16 (no clutch)  will run all the goods from the L16.

 

I was thinking about using stainless steel fuel lines but wanted to get your guys opinion on them and if there is a set that you like or are running?

 

Buy a wideband

Start with the 36

You don't rich or lean conditions breaking in a 'new' (LZ) engine

Have these SUs been reworked......?...IE...throttle shaft bushings etc...etc?

 

Basically...there are 2 issues with SUs.

Worn bushings.....affecting idle...<... base tuning

Incorrect needle profile....ratios are all over the 'map'....not good.

[jvb5577]

A wideband is on the list of parts.

Alright will use the weber first.

As for the SUs I am not sure about them yet as I am new to them.  Is there replacement bushings for them if they are worn?  Here are so pictures I got of them.  They have been off an engine for 5 years..

 

[datzenmike]

Shit they look just like mine...

[jvb5577]

Shit they look just like mine...

I know its hard to tell if everything is there.  Do you have any other pictures of the linkages and what not so I can study them before I go tomorrow to make sure everything is there?

 

They guy seems to know a lot about datsuns as he has owned a 510, roadster, 1200, and some others.  Said he used to vintage race the 510 (which these came off of) but lost interest as he got older, sold the car and engine but kept these.

[datzenmike]

Mine's missing stuff that yours has. 

 

In the '70s / '80s it was cheaper to import a low mileage domestic motor from Japan than to rebuild an L series here. Many JDM motors were cut out of cars over there and shipped here, often with stock goodies like closed chamber heads and dual SUs and manifolds and even the rare long dogleg 5 speeds.. Once here the intake and carbs were just thrown away because they didn't fit or work on our cars.

 

I've been told the flattop SUs replaced the round tops on the late L16 SSS or early L18 SSS JDM motors. The L16 SSS had flattop pistons and closed chamber heads and the cam was almost identical to the L20B cam.

[jvb5577]

Mine's missing stuff that yours has. 

 

In the '70s / '80s it was cheaper to import a low mileage domestic motor from Japan than to rebuild an L series here. Many JDM motors were cut out of cars over there and shipped here, often with stock goodies like closed chamber heads and dual SUs and manifolds and even the rare long dogleg 5 speeds.. Once here the intake and carbs were just thrown away because they didn't fit or work on our cars.

 

I've been told the flattop SUs replaced the round tops on the late L16 SSS or early L18 SSS JDM motors. The L16 SSS had flattop pistons and closed chamber heads and the cam was almost identical to the L20B cam.

Good information there!

You said they were thrown away because they wouldn't work or fit on our cars?  Do you mean these won't work?

[datzenmike]

If you took your 620 or 710 or 510 in for a motor rebuild and they bought an import motor for it, guess what. The throttle linkage on your 620/710/510 won't work on the SUs and you have no choke cables, so they simply put your intake and carb on and junk the rest. To a shop it's nothing personal, just business.

[jvb5577]

Finally got them!  Mike, I am going to need your help hooking these bad boys back up.  Everything looks to be there.  Looks like everything is original too  :D  The guy was a great guy, loved Datsuns for a long time.  Learned some great stuff just chatting it up.  Made a deal that I will give him a ride when everything is done (to bring back those old memories).  Anyways here are the pictures.

 

 

[jvb5577]

[datzenmike]

Woah. I never got mine installed or running. Better ask Sealik

[jvb5577]

Woah. I never got mine installed or running. Better ask Sealik

Do you still have them?

I will.  

[jvb5577]

Can anyone identify these for me?

 

I found this (( http://datsun1200.com/modules/newbb/viewtopic.php?topic_id=60527 )) but not sure what one is what.  I think I have the IMS system but not the anti-dieseling?

[datzenmike]

Do you still have them?

I will.  

.

Yeah all wrapped up in plastic. Had them for 3-4 years maybe more. They still have the ends of the choke cables on them where they were snipped off by the wrecking yard in Japan. Mine doesn't have all that other stuff on it.

 

 

 

 

Just like yours they haven't been de-smogged yet. It's easy enough to do. 

[jvb5577]

Been trying to find the CFM for these carburetors but have not found one thing.  Found that the Z SUs are around 150 CFM per carb for a total of around 300 CFM.  Based on the calculator I only need around 230 CFM.  I know this is just a to get you in the ballpark on what you need.  Just couldn't find it for the SSS's and wanted the information out there if anyone else needed it down the way.

[jvb5577]

Started work on the SUs.  Took some material off the throttle shafts to help with air flow, still working on it but this is what I have going so far.  I will add a countersunk screw so it wont protrude out.

 

 

 

Next will be re-profiling the needles, but before that I am going to get a wideband and new exhaust with an 02 sensor installed.  The current 32/36 weber is running very lean, pulled plugs and are white.  No power at all up in the rpms.  

[jvb5577]

Finished doing the throttle shafts today and got the carbs disassembled and cleaned.  Still has the brass floats, checked them, no leaks so will use them for now.  Gasket set is in the mail.  Still have to mock up a linkage for the cable setup, have something in mind that I think is going to work well.  Once everything is hear and assembled I will start work on the needles.  Pulled them and there are no markings on them.  Did they come from factory that way?  I have some calipers but they are not that precise and seem to be close to the m66 needles.  I am sure they will be super lean in the LZ.

 

[hang_510]

Hang_510 had one once.

HAD?!?

still running strong. maybe 30K on it now.

 

Thanks for making me relive that painfull memory once again haha.

 

 

Ha ha...yeah I fucked up my first one....lol

The trick is to tightly sandwich the HG between some wood....

Made a jig...

 

 

 

 

asked earlier, since i drilled a big round hole in the block, i just used a punch... on the second nismo HG. :rofl:

nismo HG should be available from wolfcreek racing.

 

 

I also want decent gas mileage, which is why I am trying to stay away from the thirsty webers  :lol:

i got ~25 with dual 45s on the last trip to Canby.

stay thirsty my friend.

[jvb5577]

Today I adjusted the valves.  All seemed to be a little tight while hot.  Retorqued the head, did what Mike had suggested, losen one bolt then torque it back down.  Also did a compression check after about 50 miles of driving.  Reading 184psi on all four cylinders.  I remember reading stock on a L20b was 210?  Was this right?

 

My gaskets are finally in the mail for the SUs so should have those on next week sometime.  The weber seems to be working OKAY only seems to provide good power with your foot all the way to the floor.  Really excited to see how much of an improvement these SUs make  :w00t:

[jvb5577]

Flat tops are one.

 

Mocked-up the linkage and getting it welded tonight in class.  Almost there!

 

[jvb5577]

Engine running.

 

[antonis]

Hi , i was reading your reply's  for the boring of the L blocks to 89 mm, is this the same for the L18 block or L 16? would it be a problem? i have an L 18 610 and i am trying to mod it with  off the shelf parts. thats why i was thinking the 89mm  would do the job.Also if someone done it to a crossflow head from a 910 bluebird,or maybe matched a 16v head. The later one i think is impossible, havent found the parts to test yet... Thnks

[datzenmike]

Boring an L16s 83mm out to 89mm means that you must remove 6mm of cylinder material. This would be way way too thin. L18s and L20Bs would be 4mm close but do able. However there aren't many piston/rod combos that will work with an L18 crank... I'm going to look into this.

[jvb5577]

As datzenmike suggests the L16 is not worth your time or money attempting to bore out that big.  The L18 is doable but as suggested above piston and rod combos are VERY limited.  With the L20b the block is taller so more options as L16 and L18 are shorter.  A lot of people here have bored out the L20b block to 89mm.  EricJB did a L20b that he uses for drag racing.  Great results.

[datzenmike]

Well if you over bore an L18 from 85mm out to 89mm you could fit 89mm KA24E pistons, use L16 or L24 rods. Used with an open chamber head you would have a compression of 7.89

 

With a closed chamber head.... 8.3

 

Since there is almost 3mm of wasted deck height if you had the block decked 1mm the compression would then be...

 

Open head........  8.56

Closed head....... 9.09

 

Totally do able. Oh yeah the new displacement with the 89mm pistons would be 1940cc

[EricJB]

The problem with boring an 85mm block out to 89mm, (besides the obvious thin cylinder walls) is the huge check you will have to write the machinist after he stands at the boring head for hours taking numerous passes. Even if he can take .040 a pass, that is still 16 passes, plus honing. That is the same $$; as 2 v8 blocks, .040 over. 

 

I did mine at home on my Bridgeport after I filled the block with grout. I left .010 for the hone. I could only take .020 passes and had to go half way for the first .100 before the  boring head would fit in the hole to do the 2nd half. The machine didn't have enough travel so I had to hand feed the table up the last inch. It was a PITA. At one point I fell asleep in the chair in front of the heater. It can be done, but it is a Hell of a lot of work ($$) for the gain.