My Little Goon...

[Draker]

6 hours ago, 4perrev said:

 

 

Let's start the redo.....cue that's 70's music for motivation!! 

 

[4perrev]

Very nice!!

[4perrev]

Ok, going to pull the engine and xmission out of this girl tomorrow.  Have a question.  Please forgive my noviceness here. 

 

I have an L18 in her right now, an A87 peanut head sitting around and a couple complete L16's. This is what I'd like to do:

 

(From the Jason Grey Journal)

Long rod L18

flattop Z20S pistons and peanut chamber head for 9.7:1 CR, better rod/stroke ratio for higher RPM.

Parts: L18 crank, L18 block, L16 rods, Z20S pistons

s/2+r+p: 207.66mm

piston deck height: -0.29 (below deck)

 

My question is, if I order Z20s pistons, will they fit right in without machine work?  I plan to port the intake to match SU carbs or Weber's.  I am going to clean up the exhaust as well for better a better flowing head.  One more, Z20S out of a 1980 720, correct?

 

Thanks in advance for the help!! 

[4perrev]

Anybody??

[Draker]

On 1/27/2020 at 6:00 AM, 4perrev said:

Ok, going to pull the engine and xmission out of this girl tomorrow.  Have a question.  Please forgive my noviceness here. 

 

I have an L18 in her right now, an A87 peanut head sitting around and a couple complete L16's. This is what I'd like to do:

 

(From the Jason Grey Journal)

Long rod L18

flattop Z20S pistons and peanut chamber head for 9.7:1 CR, better rod/stroke ratio for higher RPM.

Parts: L18 crank, L18 block, L16 rods, Z20S pistons

s/2+r+p: 207.66mm

piston deck height: -0.29 (below deck)

 

My question is, if I order Z20s pistons, will they fit right in without machine work?  I plan to port the intake to match SU carbs or Weber's.  I am going to clean up the exhaust as well for better a better flowing head.  One more, Z20S out of a 1980 720, correct?

 

Thanks in advance for the help!! 

80 720 was an l20b. later were z22 and z24

[4perrev]

I think you missed it. I messed up the year, but the question was, can I do all this without any machining?

[Draker]

1 hour ago, 4perrev said:

I think you missed it. I messed up the year, but the question was, can I do all this without any machining?

 

I have never done it but the l18 and z20 both have an 85mm bore. 

[4perrev]

Yeah, thought so....just wanted to make sure before I bought some pistons.

[datzenmike]

L18s are old engines with lots of wear on them. Bores can be tapered and or oval. Then you also have to hone the bores removing more material. The cylinders need to be checked for this properly by a machinist with proper dial gauges. Most cylinder wear is at the top ring. this seal needs to be tight.  

 

If buying new pistons they don't cost more if 1mm over size and with a bored block you have a brand new engine. In addition with perfectly round bores you can use the chrome or molly rings for faster better seal and longer life.

[4perrev]

Thanks Mike...Always good wisdom!!

 

Got down and pulled her heart out, before for later reference:

 

Coming out:

 

Big hole:

 

 

Also took care of some rust in the rear valance:

 

 

Thought I'd finish the day with pulling the reared out too:

 

The right rear shackle mount is bent pretty good as the car was pretty low.  Must have hit something in the past, so I'll be fixing that.

 

The bottom is in good shape with little rust, but I'm still going to coat the bare spots:

 

Overall, very impressed with how good she looks at this point.  Nothing near as bad as the two door was when I started.

 

[4perrev]

Ok...So i'm kind of confused here about the pistons to order.  I read the other posts about the Z20 pistons and know there are E and S types.  Then there were posts about buying 200SX pistons.  Does anybody know the year and model of vehicle of the right pistons when searching for parts?  

 

I've also attempted to find a clutch for this girl, but can't find anything other than the bluebirds that had the L18 engine.  Always, thanks for the assistance!

[datzenmike]

The Z20S is a carburetor engine the S type is fuel injection. All I have ever seen are the same piston for both. They are a 'flattop' though they do have small valve reliefs in them.

 

L to R Z24, Z22, Z20E, L20B pistons.

 

The distance from the center of the piston pin to the piston top is 31.75mm and most important the center to center holes of the rods are 152.4mm. This length is the same as the stock L20B piston and rod allowing them to fit the L20B as well as the Z20. The Z20E piston above is from an '80-'81 S110 200sx.

[4perrev]

Ok, that makes more sense.  As always....Thanks Mike for the clarity!!  I ordered a bore dial indicator just to see where the bore is starting at.  Will post results when I measure them out.

[4perrev]

Update.  Got down to pulling the rest of the engine apart.  Pistons out alone with the crank.  Looks like someone rebuilt this engine as the timing gear set is new and the rings might be newish.  Either way, I took it all down and measured the cylinders.  This engine has see other days, but is about to be redone with some flat tops and long rods!  Here is the measurements from all four holes:

 

 

As you can see, the #3 is the worst with a .005 difference on the 0 Deg position and a .003 Taper.  #2 is .0035 Taper, being the most.  They are all pretty close for wearing out at the same rate.  Going t bore them out .20 and drop in the 200SX pistons for a fresh start.

 

Fixed the pin hole in the gas tank and pressure checked it.  All better now.  So, I gave her a new shinny finish:

 

 

Coming along swimmingly.

[4perrev]

Finished up the rear end and hung it back up with new axle hardware.  Painted it all up to keep it fresh.  Man that gas tank is a b!tch to get all the hoses back on.  All new and blown out, so she will have a fresh line for gas and venting.  

 

Started polishing the block.  Got rid of the cast lines so far and need to polish the rest before sending it in for a line bore job of .20 over.  Like DMike said, "Start with a fresh block!" Can't wait.

 

Here's the rear end set back in place:

 

 

[4perrev]

Started the front end dismantling yesterday.  Wow, there were many a bolt that was not tight and many did not have lock washers.  Glad I decided not to drive her right out of the gate after buying.  Good news though, she has 280ZX strut already, so I ordered the same coilover sleeves and camber plates from T3 Tuning today.  Will get down to cutting the stock perches off in a couple days and getting them ready to setup.  

 

Already have all the steering ball joints ready to swap out, but have to clean and paint em first.  The brakes will get a thorough clean and paint as well.  Plan to pack out to Ace Hardware and buy some new nuts and bolts for all these parts and start fresh.  Going to make her all pretty like the Dime realized.  

 

Still have to name these beauties', but gotta find the right names!  

 

Oics to follow, soon!!

[4perrev]

Well,  finally have the block off to the machine shop for a bore/hone/decking.  Should be done soon and going to be super shinny to boot!  Front end completely disassembled with the front strut done in the usual coil over treatment.   Stripping old paint off and getting her ready for a nice engine bay.  Oics coming soon.  Just sooooooooo damn busy!!

[4perrev]

If I could ever break free of the Honey Doooo list, I would be in the Goon again.  I intend to see her this weekend, well, my weekend anyways.  Will post those oics here soon.

[4perrev]

Got my block back from the machinist.  It is all nice a tight now.  Bores are perfect and I had the top surfaced.  Machinist told me the top was off a bit, especially where the head bolts were.  They were pulled up pretty good.  Once surfaced, he found a crack on one bolt and put a steel insert in to pull the metal back together.  Here's the block:

 

 

Here's with a new piston sitting in its new home:

 

 

Crack with the new insert:

 

 

Block from underneath with all the castings smoothed out:

 

 

And, painted:

 

 

Now all I gotta do....is put it all back together!!

[Draker]

I’m kinda surprised he didn’t weld that crack then deck it. He would know better than me though.

 

looks good!

[4perrev]

He works a lot of marine engines and said it will be no issues. Spoke with Troy Ermish also and he suggested the same. Two for two is good with me! Thanks, she’s coming along well.

[4perrev]

Finally finished scrapping out all the old paint from the engine bay today.  No more blue under the hood....well...except for the engine.

Before:

 

 

And....the new look:

 

 

Still not sure what color to go with under there for a final, but will have to figure it out soon!

 

Front suspension going to be reinstalled next, with the new coilers!!!

[mrbigtanker]

So I appreciate were you are going buttttttt, why did you not remove blue on top by cowl, and is that can spray paint ?

[mrbigtanker]

On 8/5/2020 at 10:19 PM, Draker said:

I’m kinda surprised he didn’t weld that crack then deck it. He would know better than me though.

 

looks good!

I agree, I would of had it fixed period for piece of mind.

[4perrev]

Tanker,

 

      I’m going to remove all the blue as I go. This is chassis saver, the black that is. Base coat as it is a rust inhibitor and will protect it forever. Top coat over this.

 

not worried about the crack as this will hold it and not have any issues.