Another Z to see the roads again...

[siteunseen]

I've always balanced them by removing off the rod instead of the piston. Seems like the same end result is what we want. Total weight per assembly and I ground off the sides closest to the pistons. As the "bluebird of optimism" says "whatever works".

@Captain Obvious

[Captain Obvious]

Haha!!!   

[ETI4K]

Wow, the month of Aug has certainly blown by.  Just got back from CO and Z-Con.  Lots of very nice cars, and I met some great folks.  Absolutely will be planning the Birmingham trip next year.  Maybe next time I'll register for the closing banquet. 🙄

There was one car in particular that I was drawn to because the (original) owner, Robin Bolz, had taken so much care to build his car in a way I don't think I've ever seen before.  The build team found some great hardware and made some interesting changes that turned out really well.  I love how modifications were made primarily to clean up unused mounting points, hide/mask certain elements that he didn't want to see, and to use design elements to draw the observer's eye.

I think I spent about two hours talking with him and his "general contractor" on the build - both really friendly and helpful.

The top of the valve cover was cut out and a flat piece was welded in.  The "L28 Turbo" and grooves were machined in by CNC.  Note the oil filler.  The cap has an o-ring seal on its mating face with the welded-in plate.  He modified the OEM cap to make it a tool for operating the new one:

 

Nice firewall bulkhead:

 

Custom-made injector retainers:

 

The heater supply hose was changed to a rigid pipe that was routed behind the coil mounting plate.  This required a custom fitting for the lower radiator hose:

 

With few exceptions, every hose/tube clamp used these fittings.  According to Robin, when they found them, the company was going out of business, so he bought all they had.  I plan to reach out to him to see if he'd temporarily part with one so I can utilize "prior art" to make some more. 

 

He wanted the fuel rail to run parallel with the valve cover, but the intake body runs at an angle to it which he thought detracted from his design intent.  So they made a cover for the entire intake to mask its "angle" then mounted the fuel rail on top of it.

Note the battery cable treatment:

 

No one could recall if the new location for the valve cover vent hose was baffled internally as the work was completed about 10 years ago.  The consensus was that it was not - since there's no room for anything behind the last cam tower.  The hose runs to a catch can and there's no way to determine the can's fluid volume, so they just open a drain valve periodically.  The car is NOT a daily driver - big surprise there, right?

 

 

[SteveJ]

Yes, that is a beautiful build. I saw it at ZCON 2011 in Savannah.

[ETI4K]

Been hard at work getting what seems like nothing done.  I've been focused lately on acquiring and having at hand everything I will need to build my motor so that once I start the assembly, I can proceed until it is fully assembled and ready to bolt in.  I am so tired of having to stop and start different tasks because I am waiting on parts, or services (machine shop, plater, etc.).

Aside from the usual bits, I will also be:

   - Modifying the N42 intake by deleting all unused mounting holes and vacuum ports, relocating some fittings, adding one new one for IAC valve, and smoothing the outer surface in prep for powdercoating.

   - Deleting the distributor and going with a Jeep CAS.

   - Modifying the valve cover by shaving the plug wire bracket holes and breather hose fitting, and relocating the breather hose to the rear face.

   - Removing casting flash from the block interior.

   - Adding a low oil level switch to the oil pan, and removing all its failing OEM black paint and primer.

   - Modifying the coolant inlet fitting to convert from rubber heater hose to polished metal tube (I'll convert back to rubber hose at the rear of the block) - this just for aesthetics.

   Going with CPP and so I am having a mounting plate and other parts made - a friend has access to a Trumpf laser so the parts will be free to me.  He's only had the model file since September 7th....of 2020!  I am confident that given another several months, I'll have the parts (to include a 36-1 trigger wheel, sensor mounting brackets, and timing marker). 😁  Ahh, it's good to not be in a hurry.  That said, I would like to finish this car in my lifetime.

 

Pics to follow soon.

 

 

[ETI4K]

The struggle of the day...finding and selecting pistons.

I cannot find cast pistons in .50mm oversize.  I can have custom pistons made for me - oh boy 🙄 - at the low, low price of $1100 a set.  This versus $250 for cast.  Okay, so I have come to grips with the newest new budget for my build (insert sucking wind sound).  The problem is what, specifically to order.  It's one thing if you just buy what's available, it another entirely when JE asks you for every detail to be specified.

So the biggest issue is valve reliefs or not.  This of course depends on, among other things, the cam profile - which leads to of course, should I get a new cam?  When you start asking others for recommendations, you start getting lots of helpful input.  The problem with that is, everyone may have different ideas of what concepts such as tractable, power, acceleration, and smoothness mean, so it's difficult to plug that information into my brain.

I am trying to build a fun, good weather car.  In years past I drove my cars as though my hair were on fire - always trying to improve my commute time, seeing how fast I could run through the coin-drop toll gates without having to stop (requires excellent aim), let's see if I can get this car sideways here (very easily done in an older 911!).  All of that done without disrupting other drivers or causing them to brake or alter their lane position.  Ahh, what fun.

This car won't be driven that way (well, maybe just a little).  But I want it to have the a** to get it done if needed.

The plan:  Targeting 10.5:1, 7500 redline, MS3 for ignition and fueiling, coil per plug, full sequential EFI, lightened flywheel, Sean's exhaust, coilovers - lowered, etc., etc.  The car has to be "tractable" and not have "driveability" issues.  It will not be raced, so top end only power is not the target.  This would suggest a low-mid-range power band, but more power comes with higher lifts and duration at higher rpm than low-mid cams produce.  Too bad you can't virtually "drive" (as in a simulator) a car with each different cam profile in it to see/hear the differences. 

This motor had a Crane Stage II (.460 lift, 272/282, 26 degrees overlap) in it when last built.  The motor sounded good, was easy to drive, but never developed the power it should have for that build.  The car did have a crappy restrictive exhaust that I was always going to replace but never did before I took the car off the road for this restoration.

You can see how I get wrapped around the axle on this stuff.  Lots of options, none of which can be fully quantified, and a limited budget.  If I were made of money, I might just buy all three of Isky's cams and see what happens with each. 

So, since I am not made of money, may I ask for more input and suggestions on this topic?  All comments are most certainly welcome.

Edited September 23, 2021 by ETI4K

[Patcon]

Dizeased would tell you more cam.

He's built half a dozen Z engines, atleast

My first thought is what king of head porting is being done?

[ETI4K]

The current plan is to just port match the intakes, deflash and mildly smooth the intake runners and polish the exhaust runners.  No plan to work the chambers.

I'm having a discussion with the guys at Top-End Performance today about this topic.  I sent them the specs and plans for the car by email, and they've asked me to call - sounds like I've missed a couple things.  I'll provide an update here after talking with them.

[ETI4K]

Wow, what a conversation with Steve at TEP.  His first comment "...was, why, why, why would ANYONE use a P90A head when what you really want is an N42 or E88?  You can't use anyother cam on that head."  I did mention that it had been converted to mechanical adjusters.  He suggested that then you have spend a lot of money getting the longer valves, tower spacers, etc.  Then mentioned that "knuckleheads" do the .080 shave, made a reference to dumpster diver engine builders, and so on.  So after about ten minutes of that, he told me he can do anything I want wrt pistons and cam.  The only detail he mentioned was that he had the perfect grind for me at .490 and 284 duration.  His JE pistons (he doesn't recommend anyone else's) are $1150 and a cam regrind (on a non-performance core) is $199.  Interesting way to do business.

The only value I can see in using them is that as long as I provide accurate dimensional data, such as block height, rod length, bore size, etc., then the pistons I get will not have any interference with the valves - iow, valve reliefs, if needed will be added and only enough of a cut will be made to provide adequate clearance - keeping my CR where I want it.  BTW, I called JE several days ago and they will sell their pistons at $150 each.

[Jeff G 78]

I used TEP years ago to lighten a flywheel, but yeah...  That's a pretty narrow focus that there is only one way to build an engine.

[jonathanrussell]

Many people would ask why why why anyone would use a n42 head unless you are going to weld and reshape the chamber. 

[Zed Head]

The classic way a speed shop tries to get business.  Trash the other guy or what you have so that they can sell you what they have.  Beat you down then tell you that they can save the day. 

Sounds like you are aware.  6 x $150 = $900.

6 hours ago, ETI4K said:

He suggested that then you have spend a lot of money getting the longer valves, tower spacers, etc.  Then mentioned that "knuckleheads" do the .080 shave, made a reference to dumpster diver engine builders, and so on.  So after about ten minutes of that, he told me he can do anything I want wrt pistons and cam.  The only detail he mentioned was that he had the perfect grind for me at .490 and 284 duration.  His JE pistons (he doesn't recommend anyone else's) are $1150 and a cam regrind (on a non-performance core) is $199.  Interesting way to do business.

 

6 hours ago, ETI4K said:

BTW, I called JE several days ago and they will sell their pistons at $150 each.