LZ22 Engine

[kezark31]

what head bolts or studs are you going to use?

[MicroMachinery]

what head bolts or studs are you going to use?

 

Haven't thought about that; figured stock L-series head bolts would work. Wouldn't you think?

 

So I started doing some port matching on the L20b intake and U67 cylinder head. Here are some shots of where I got to before stopping for the day.

 

This is after using the gasket and paint pen to mark the outline of where I'm going to be cutting.

After a little grinding.

Here's the gasket over the ports. I left a little meat around the edges for when I smooth everything up.

[hang_510]

Ok, so I got some pictures of the Z22 HG up against the block. I don't want to get creative with "paintbrush", so my finger points to the places where the coolant passages are in the block, but not the HG.

This is the largest one.

if there are not matching holes in your head, no need to make holes in the gasket.

 

 

i drilled maybe 4 holes in the block to mate with head for coolant flow

[mike]

Do you have any pics of the gasket against a Z head to see what similarities/changes there are in the coolant passages?

[MicroMachinery]

Got some more port matching done. Here are the goods.

 

Have to finish a couple things this afternoon then it's off to the machinist to have the valves ground.

Still waiting on my connecting rod bolts.. <_<

 

 

Do you have any pics of the gasket against a Z head to see what similarities/changes there are in the coolant passages?

I have the Z22 head, so I'll try to remember to get the pic you're wanting.

[Jester]

Nice work on matching things up.

I noticed your U67 has the water passages for the intake open. The one I just picked up doesn't have them opened. In the block surface OR the intake surface. Wondering whats up with that.

[datzenmike]

I don't think any U-67s had the water passage open. All the car and truck ones I have seen use the exhaust heat to warm the intake. The intake and exhaust are bolted together in the carb area. there is an opening in both about the size of a baseball that is covered with a thinner ribbed metal plate. There is a bi-metallic spring loaded flap gate that directs hot exhaust against this plate to heat it up. Incoming cold air and raw fuel are warmed and better vaporized. The motor runs better on cold start up and with fewer emissions. As the bi-metallic spring heats and unwinds it turns the flap gate and less exhaust heat is used. On North Am cars this was known as a hear riser valve.

 

This one is from a '75 620 but both my 710s ('76 and '77) have it too.

 

The cover plate that fits and seals between the exhaust and the bottom of the intake (shown) Neither manifold is any good without the other. This intake is the one used by Jason Gray in his draw through turbo. The carb side was sealled and the boost air and fuel fed through the bottom hole.

 

It was used on '75-'77 L20Bs and discontinued on all '78 motors with the W-58 head.

 

The coolant runners on the earlier L16/18s and the later L20Bs serve a dual function. True, they warm the intake to help evaporate fuel and make it more drive able and fuel efficient, but in extremely hot conditions it also helps to draw away excess heat keeping the intake air temperature more even over a wider range of outside temperatures and conditions.

[Jester]

 

I was just asking because his U67 has water passage holes for the intake. Made me wonder.

[datzenmike]

Likely drilled out so that the earlier L16 square port exhaust manifold could be used. Once that is done the intake has to be changed as well.

 

This can be run with or without the water intake. You don't need to plug the holes. The intake gasket will seal it just fine. If you are running an intake with water in the runners the outlet, in front of the carb base, must be plumbed into the return lower rad hose inlet to the timing cover.

 

 

 

 

.

[Sealik]

What are you dropping the LZ into?

Your 4x4?...... :D

[MicroMachinery]

Nice work on matching things up.

I noticed your U67 has the water passages for the intake open. The one I just picked up doesn't have them opened. In the block surface OR the intake surface. Wondering whats up with that.

 

It was like that when I got it. It was on an L16 that was in a wagon I bought, but the L16 frozen up something fierce. Kept the head and wrote the block off as junk. I'm positive that they were drilled, like D-Mike said.

 

What are you dropping the LZ into?

Your 4x4?...... :D

Yessir :)

 

... and nobody has anything to say about using this Z22 gasket on the L-series head(with very slight modification, of course)?

[Jester]

Just cut the front off and silicone it. Works for a SBC intake manifold. Like Mike said, It just keeps back oil spray. It would be different if it was under a lot of pressure.

[izzo]

Just cut the front off and silicone it. Works for a SBC intake manifold. Like Mike said, It just keeps back oil spray. It would be different if it was under a lot of pressure.

 

 

^^^

[Sealik]

more costly... but the nismo comp HG (88.5mm) only needs 1 hole & no grafting.

 

 

How much...?..I googled that nismo HG and got squat :blink:

[hang_510]

It just keeps back oil spray. It would be different if it was under a lot of pressure.

its a lot of spray.

 

mine leaked using RTV w/o modding the HG.

 

 

I noticed your U67 has the water passages for the intake open. The one I just picked up doesn't have them opened.

I don't think any U-67s had the water passage open.

i have 1 of each.

[hang_510]

googled that nismo HG

headgasket

 

11044-A7651

 

http://www.nissanparts.cc/cart/?pn=m-11044-A7651

[Sealik]

i did for the LZ22, but not for the LZ24 :unsure:

 

Did you still have access to pull the dipstick on the LZ24?

I'm thinking yes......but a bitch?

I'm gonna try to keep the stock location.....if at all possible

[datzenmike]

Easy, just check the oil when motor is cold or keep a leather welder's glove handy.

[Sealik]

Easy, just check the oil when motor is cold or keep a leather welder's glove handy.

 

Ya....I figured I might be able to pull it with a glove and or 2 :D

Soon as I mock the IM/EM to the head and block, then I can grasp all the clearance issues.. :blink: ..including the master cylinder.

Rather not 'calibrate' the dipstick on the lower end......etc.

[hang_510]

Did you still have access to pull the dipstick on the LZ24?

yes.

dual webers and i could check it hot w/o issue, bare handed.

 

not on the LZ22 though.

relocated to the other side.

[datzenmike]

I think the master will clear but not the L air filter. They did it somehow on the '80.

[banzai510(hainz)]

if you live in a warm area I would not make water passages in the head. But if you do I use a 1/4 drill bit.

 

If your going to run sidedrafts then YES DO NOT drill any holes

 

PS I lke the port matching Hopefully you did the top where the carb sits on the carb adapter. make a nice smotth transistion.

[MicroMachinery]

Been very busy lately with the holidays and work. Finally got a chance to sit down and update my progress.

A week or so ago the lion's share of my parts came in, so I've been going at my own slow pace towards the completion of this thing. Pics of the goods:

Yes... :cool:

I also sent the head off to my machinist to have the valves done. It's lookin' pretty sexy.

Mmmm... fresh 3-angle valve job..

 

***

 

So last I wrote I was waiting on those ARP connecting rod bolts. As soon as those came in, I installed those and ringed the pistons. Those dropped in the same night. Took about a week long break(not really a break, just didn't have time), then yesterday got back at it. I got the timing guides installed, the brass freeze plugs in, and took my chances again at modding the Z22 headgasket. I am very pleased with my results this time around.

Instead of using punches, I took the gasket to my drill press, then slowly and carefully drilled out the only 2 cooling holes that the L-series head had in common.

^^^ Much better than my last attempt. The one below isn't the most beautiful thing, but it certainly is functional and I didn't mess up the gasket in the process. Either way, more coolant is gonna flow now. ;)

Now, onto the timing cover section of the headgasket. I did some looking and head-scratching, and didn't see any point in ruining a perfectly good L20b headgasket when everything I needed was present on the Z22 gasket. I first started out by putting the HG onto the block, then placing the head on top of the gasket. I then traced around the edges of the base of the head onto all the areas that stuck out. This served both to clean up the look of the block, and give me the tab for the corner of the timing cover.

Observe..

I knew it would work, but I was actually astonished at how perfectly the tab fit into place. I didn't have to modify the bolt hole or anything. Even the outside edges line up with the edges of the gasket that I'm grafting it onto. Nice. :)

[MicroMachinery]

Alright, so after some biting and clawing, I got the engine most of the way assembled. I was about to put the pan on, and I noticed that on the oil pickup tube that was specific to the 80 720 4x4, there was a threaded hole for a bracket. Crap. When I got the truck, along with the oil pickup and pan, there was no bracket with it. I searched around and found what I needed.

I called around, and apparently, there were none available through all the Nissan dealerships in the country. Ok, time to get creative. I first fabricated a very sturdy bracket from 1/8" strap, but it didn't work due to the thickness in relation to the main bearing bolts.

The next thing I did, was went out into the back 40 with some metal shears, and began cutting sheet metal from the damaged fender of our rally Sentra. The metal was a little thin, so I cut two segments. Here they are w/ rounded edges and holes drilled.

In order to reach from the strainer to the far main bearing cap bolt, I had to give it a curvature which followed the shape of the main bearing cap. After removing a main bearing bolt, I ran the bolt through the hole in the opposite end of the bracket, and torqued it to spec.

After that, the pan went on, and there it sits.

I have a few more pieces to glass bead, then on they go, and hopefully I'll be able to round up some of the guys to help me push the 720 into the shop for the install.

[Sealik]

So....you just 'drilled' out 2 holes in the HG?

Correct?