In the book, he has a picture of the angle of the installed shaft relative to the distributor mounting face.  I've tried pulling and reinserting the shaft for about 30 minutes (slightly rotating it this way and that each time) and can't figure out a way to get the angle any closer to what's pictured.  I can either get it installed way more clockwise, or way more counterclockwise. How important is this exact angle?  

Tom's instructions:

My best effort so far:

checked for vacuum leaks at carb and manifold.

Swapped carbs around and symptoms didnt follow the carb.

Replaced Coil, Spark plugs, plug wires, Distributor cap and rotor.

Added a ground strap to engine block.

Confirmed good power and ground to MSD box.

None of this has had any change and at this point, I’m totally scratching my head. Does anyone have any ideas?

I bought the jenvy 45s, injectors etc.. from Datsun Spirit.  I will probably do a haltech elite 750 ecu.  I got a hoke trigger kit for my stock 240z pulley and will do some sort of cam sensor from the dizzy spot.  Goal is to look basically period but be EFI.  I will re use my SK intake.  

The head appears to be ok, but will be checked out thoroughly.  The cam no longer will spin in the towers like it did - it spins by hand but keeps hanging up a bit in the same spot of each revolution.  Since there was piston contact to one exhaust valve which bent the valve and knocked a rocker off, perhaps the cam is bent.  It will be checked and replaced if necessary.

Some things that I have been thinking about:

Why did the "new" motor blow up? Basically, it looks like the #1 and #2 main cap bolts backed off while the engine was operating. This cause oil pressure loss to the bottom end.  The number #2 rod bearing experienced a metal forging process until it was many times thinner than when originally manufactured, then the #2 rod cap broke in half, the rod bolts broke, the #2 rod broke off below the piston pin... and this middle section of rod #2 then found its way into the path of rod #1, etc. etc.

The main bolts were torqued to 45 ft lbs.  Factory spec was looked up at the time the engine was built (I think it was 43).  My engine builder was very concerned about such a light torque spec with those bolts - he was concerned about adequate bolt stretch.  He told me so when the engine was built.  

To attempt to address, we will be replacing the stock bolts with ARP hardware.  

So, why did the main bolts back out?

I really don't know.  The rest of the main bolts were tight at the time of inspection and dissembly.  The #2 bolts were both so loose that I removed them by hand.  #1 had just enough torque that a wrench was needed to un-clock them about 10 degrees before I could remove them with my fingers.  If I am guessing, then possibly harmonics/resonance of the crankshaft came into play.  Another piece of evidence that I think points to this are the flywheel bolts:

I have no idea what caused 4 of the 6 to collect a couple of crankshaft threads at the end of the bolts... and weld all that shite together.  It made for no fun removing them.  It is interesting to me that only the last 1/8 of an inch of the bolts was affected for four of them and two were essentially ok.  

If it matters, there were some rather unusual driveline forces in play when, at north of 6500 rpm, most of rod #2 broke away from below the piston pin and got caught in between the big end of rod #1 and the block.  This LOCKED the engine completely at just north of 100 MPH.  Could going from high-ish RPM to NO RPM in a split second... in conjunction with a 2500 lb car on sticky race tires have yanked the flywheel so as to cause this to happen with the flywheel bolts? I am doubtful.

What if it is a harmonic issue?

Well, who can run their L series between 7000 and 8000 RPM then?  I've read in many posts that running in the 7300-7500 RPM range is a problem and it is to be avoided with these engines.  Even with an 8k or higher cam, depending on the track, won't there will be significant amounts of time spent per lap between 7300 and 7500?  Must we all build the 6 cyl L to rev no higher than 7200 RPM?  Or, must we all go salt flat racing where we turn 9000 RPM plus, so we never dwell in the evil zone for longer than a fraction of a tic of the second hand?

The current plan:

I have sourced two N42/N42 engines which the engine builder will retrieve on Monday.  The plan, for now, is to build the engine nearly the same as before with at least these changes:

• ARP main studs will be used instead of the stock bolts
• When I have the crankshaft offset ground, I may not have it lightened this time.  From what I have been able to determine, the Rebello BHJ damper I am running was tuned for an L-28 stroker crank.  More research will be done so I can understand how best to proceed.  I think it is possible to have BHJ tune a damper for an engine on a dyno.  I will look into this. 
• Dry sump oiling system - I believe it was Clarkspeed who said he was running a Nismo comp. pan and his Accusump was working in turns 6 and 7 of Road Atlanta.  I don't have an Accusump, and my Nismo comp pan was damaged quite a bit when the rods let go.  Since I don't really know the cause of my engine failure (perhaps I was just getting oil sling away from the sump causing oil starvation and main caps #1 and #2 came loose after the grenade went off inside the front of my engine), going dry sump seems wise in retrospect.
• An Electromotive Tec GT and TWM fuel injection set up will be used instead of the Mikuni 44 set up.  I couldn't get the jetting to do what I wanted with my cam and the distributor with Crane HI 6 and optical pick up was still indicating some spark timing irregularity above 7k or so rpm. Going distributorless will allow me to move the rev limit up to the full 7700 RPM spec'd for the cam.  At least at Road Atlanta, a 7700 RPM limit may have me spending less time in the evil RPM zone as the Hi 6 was holding me at a 7400 RPM limit on the back straight for a while before I would brake for turn 10a. 
• The cam I am running was developed with titanium valves. The intakes valves will be switched from stainless to titanium but I will again run the stainless exhausts for durability.

That's where I am for now.  I'm sure things will change a bit as we go... It's too bad I can only devote part of my time and efforts to my hobby.  That makes the learning come slower and at a much higher cost.

1. DBW pedal, can be drilled to fit stock location. Has a metal base that can have stock pedal welded too
2. Crank sensor. 58x (60-2 teeth). Missing teeth should be 81 degrees before TDC. Use a 2.4 ecotec 58x wheel welded to the front pulley. Contact me for centering jig if you want one.
3. Cam sensor. 4x weird pattern. Gap in halfmoon should be under sensor at TDC. Can mount to cam gear if you machine it shorter (will need endmill or lathe which I don't have), can mount to distributor if you cut distributor case half off.
4. Throttle body is much larger, will need an adapter. I made a custom 3d model for it, contact me if you want one.
5. Injectors are 14mm, tall, flow ~27lbs( ~32lbs for 08+). Will fit directly into aftermarket fuel rail.
6. Knock sensors seem to just fit against block fine.
7. Coils need a 1/8" or equivalent mounting bar, but otherwise are direct fit.
8. The typical ECU wiring for any modern computer, tune, unlock.

In the meantime I would like to restore my dashboard and replaced a few tings like the bulbs and the speedometer. But for that I need to know if I can remove the dashboard and still be able to start the car. Does anybody know if the 280z can be started without a dashboard?

Bill

From 3 years of searching, aside from one machine shop, this seems like a hopeless, useless attempt.

This is not going to be quick, easy, cheap, or probably logical for that matter.

There is no reason what so ever to chose this over say, any choice of RB engines, or other 6/8 cylinder engines that actually make sense. However, I've got about a year and a half of solid research/drawings into this, so I'm in it for the long haul.

So here it goes.

As far as L series parts, it's going to be the block, crank, and rods, oil pan, oil pickup, and that's probably it. I've got an F54 block that saw about 10k miles before it sat in a field for 15 years, along with the crank and rods to go with it.

The Head: Currently the game plan is an RB head, as I really only need the bolt holes and cylinders to line up.

The front plate: This is the big killing point of the majority of these projects. So far I have drawn up a complete front plate, to block off all oil passages, re-route water lines, etc, and am mating the very bottom of the Stock L front cover so that the maximum number of stock parts from whatever engine can be used with a minimum of custom fabbed one-off parts. The plate I have drawn up will eventually be making it into CAD files fairly soon that I plan to make available to HybridZ members, for free, hopefully.

Block Modifications:

The big problem with this engine will be coolant, as external oil lines and oiling modifications have been beaten to death and tried and tried on hundreds of engine designs with success. That said, the problem with the RB and L series, is the direction of flow is essentially backwards, rotationally speaking. If this happened, there would be very little flow on the exhaust side of the engine, leading to a horrifically short engine life. The block will have to be filled with Devcon, or preferably welding on the intake side to rotate the direction of the water jacket, with new holes machined on the exhaust side of the block, along with being stabilized to allow correct flow throughout the cylinders.

There is a long list of modifications that I will be posting as I find time.

Moderators: I really wasn't sure an appropriate title for this, so change away.

I really don't expect this to be taken too seriously until I get some pics and dimensions up, but they should be coming soon.

~Bob

Link:Turbo Intercooler Intake Manifold Kit for 75-78 280Z Fairlady Z L28 L28E Engine 500HP

• What internal components should I upgrade or swap (e.g., pistons, head gasket, oil pump)?
• Which turbo setup works best for this kind of build?
• What ECU or fuel management options are reliable and relatively straightforward?
• Any tips on sourcing parts—junkyard compatibility, aftermarket suppliers, or trusted vendors?

I’m not looking to cut corners, but I also want to be smart and cost efficient about sourcing parts. If you’ve done this swap or have solid info, I’d really appreciate your input.
Thanks in advance!

Right now, the crank case vent runs to the balance tube through a PCV valve just like oem. No issue there. The valve cover however has one of those tiny filters, since the stock airbox for the carbs is gone. 

My understanding of the system is that the crankcase is used to draw air out through vacuum through the intake. The valve cover is designed to draw in fresh air at idle to the engine, but under WOT would not be pulling air. 

I want to run a single catch can to tie together the crank and valve cover hoses together, and run the outlet of my catch can back to the PCV on the balance tube. I'm wondering if that's correct, or if I have to run the valve cover vent separately to a location in front of the carbs to pull fresh air or if I can connect it without a PCV to the intake.

I found this picture on here, but the outlet going to intake does not indicate the PCV valve. which is what has me questioning my idea. 

pistons . LD crankshaft offset ground with Eagle rods to get me 3.2 
The MN47 head was ported by me - no flow bench , just seat of the pants cutting. Ports were only opened up to 35mm  . Manely 44/35 swirl valves with bronze guides . The head is at 39cc . The cam is a 535 lift Bonk cam . It’s advertise 535 , but I could only get that with 0 lash , so it’s more like 520 lift .

Engine management is a Megasquirt 3X with 270cc 14mm injectors running on a stock N42 intake with a 240sx 65mm TB . 

Exhaust is a MSA 6-2 header with dual exhaust to the back . 
BHJ damper , Kameari oil pump and chain tensioner . 
GM alternator 90 amps

D-585 ignition coils with MSD wires . 
4 row radiator with single electric fan 

cam sensor from 4.0 Jeep modified by me . 
flywheel 12lb steel that doubles for my CAS . 

Currently rev limiter is set at 7500 . Power drops off before then with current cam and induction .His build wouldn’t have happened except for the knowledge base on this site . Thanks for all that contributed their knowledge . Dyno session is schedule a month out . Currently using butt dyno and GPS speedo to do 0-60 times . It will also do quarter mile . Best time is 4.77 to 60 with some tire spin . Timing is 37 degrees max with a 13.0 set for WOT AFR. 

I was wondering if many of us would share our weber jet sizes vs different setup L series 6's.. Just to help others tune their weber fed ZEDs.

My 240z has the original block bored out to around 2.5l with a appox 280-288 degree cam or 74 degree depending on how you read them(tighe cams au-will edit with cam grind number later).

No porting- valve grind - 6,3,2 extractors 2.5 inch system.

Tripple webber 45's on lynx manifold running:

135 mains

155 air correction

32mm chokes

f2 emm tubes

35 accerator pump jet

f955 idle jets

"sock filters"

This setup gets me appox 21 MPG and revs out very hard above 3500rpm..

BUT is a bit coughy and sick up to 3000rpm which i think is mainly due

the "big" f2 emm tubes and the small 35 acc pump jets.. I also think that the 155 air corr jets is a bit small.

I hope to change the emm tubes to f11(or f15), the acc pump jets to 50's and the air corr jets to around 190-200..and i will post here when i do to show progress.

Anyone else wanta share their setups?

btw anyone else have any extra jets for sale in au(pm me!!)???

Hi everyone. Some of you know me from my  DIY EFI manifold project

http://forums.hybridz.org/topic/63445-making-my-own-efi-intake-the-first-casting/

Well now I’m tackling a DOHC head.

 Some history:

I get a PM from Tony D in September of 2012 about the Goerz-Paeco DOHC L6 Head coming up for air.http://forums.hybridz.org/index.php/topic/109116-dohc-l6-was-somebody-looking-for-the-goerz-paeco-dohc-l6-head/?&gopid=1020596

Which led to a brief discussion about what would be involved in producing a head. And that was the end of it... Or so you thought. 

Tony and I started trading emails about the feasibility  of producing it and what kind of heads we could use as a donor for the valve train. Tony suggested bringing Jeff P on board because of his work with cooling the L6 head. Tony and I kicked around RB and KA motors for a while and then Tony suggested checking out the Honda K20. Bingo. Removable cam towers, factory roller rockers and a plethora of aftermarket parts. I called one oh my clients that is big in the import drag market and  procured an old K20 head. I did some quick measurements and decided that it was probably workable. And so the journey began.

The idea is to use the cam towers and valve train from a K20.

I grabbed a quick scan with my white light scanner of the exterior. It’s dirty because I’m only using it as a reference scan to design against.

I imported the scan into my solids program and then proceed to replace the mesh with solids.

 

 

Jeff provided me with a great CAD drawing of his head gasket to work from. I decided to take a module approach to model the head. I made a single cylinder complete and the copied and offset it for the other cylinders.

 

I then pulled the solids together to create a single model.

 

At this point I was at a standstill until I could figure out what to do about the timing chain.

 

Jeff and I had a long conversation about pros an cons of various designs. The preference would be a single chain so I ordered up a K20 set to see if it was workable. NOPE.

Lower timing gear is too small to bore out to fit the L6 crank. Back to the drawing board.

I decided to give the KA set a try. I decided the Altima set would be a good choice as it’s only a single row chain up top. With the roller rockers I don’t think you need a double row.

 

I did a rough mockup on a piece of wood mounting all the pieces. 

 

Then I machined a chunk of plastic so I could actually mount it to the block.

You can see I’m trying to incorporate the KA guides and lower tensioner but that won’t happen without a new lower timing cover.

 

Here is the lower section with stock modified L6  components. The only tricky bit is I need to remove one link from the chain. I think this is a workable solution.

 

Now I could finish modeling the front and back of the head.

 

Next the front timing cover. The water outlet exits the head in the front and makes a 90 degree turn through the timing cover where the thermostat housing will mount.

 

 

Now the valve cover. The K20 cam towers kind of dictated the overall size but I was still able to get the styling I was looking for. I was trying to have the flavor of the S20. I’m still tweaking the design but so far I’m pretty happy. The “NISSAN” and “3000”  will be machined in so they are kind of placeholders for now.

 

 

After talking with Jeff about his testing on coolant flow I decided to get the most out of the 3D sand printing process as I could. I designed a water jacket that would be pretty hard to duplicate traditionally. There is a lot of surface area so hopefully there will be large improvements in cooling.

 

Here is a nice shot of the intake and exhaust cores, water core, and upper tensioner. You can see where the cross drilling will go to supply oil to the head, tensioner and idler gear lube.

There will have to be additional oil supplied to the last three cam towers as the single feed in the front won’t cut it. 

 

Here is a cross section of the head. The cut plane is through the center of one of the intake valves so the ports look a bit off. There is machine allowance on the bottom so the combustion chamber is a little larger than it will be after surfacing.

 

 

Well like I said in the original Goerz-Paeco post I think this is a very viable approach to producing DOHC head.  Should make for an interesting conversation.

 

 

Derek

 

 

 

Oh and one more thing.

What good would a thread about casting a head be without.......

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An actual casting.

 

 

 

We poured this Monday and I just got these pics from the foundry today. I haven't seen the head personally but we're pretty sure it is good enough to move forward with. 

 

Still lots to do but you can't imagine how happy I am to get the first one right. 

 

As long as things proceed as planned I will be selling these. There is still a lot to figure out. I have the foundry working up some pricing for me and I'll post that as soon as I can.

 

Thanks for looking

Derek

EDIT: I now have a blog about this head on my site. I'm going to continue to post here but the blog is a condensed version of what you see here. There is a FAQ on the left side bar that has a lot of data. If you are new to this build you may want to come up to speed there and then start following it here as there is a lot of great back and forth that isn't on the blog.

http://www.datsunworks.com/Blog/

I don't have the parts in my hands to take exact measurements, but it seems like you can take an L28 with dish pistons, swap in 240z rods (2.65mm longer) and then remove about 2.15mm from the dish piston tops. This should get them to be basically a flat top, with depending on head gasket and block deck height, a nice tight clearance. 

You get the performance benefits of better rod ratio, smaller trapped area between top ring and piston top, and higher compression for minimal costs. 

Anybody do something like this before?

So today I started my Z and the cranking was incredibly slow, it took 20 seconds of very slow cranking and the car started. Then I drive it for a bit and It seems to be fine. 

I went to O'Reilly's afterward and have them test my battery and alternator, the machine at O'Reilly says it's a bad alternator and battery. I'm worried that the alternator regulator is zapping the battery because on my ammeter I see rhythmic jumps on charging only when idle. When I turn on my headlights or start driving a little faster, the jumping goes away. 

My alternator is the old style with external regulators and after cleaning The regulator a little bit, I started the engine again and the jumping is less but still exists. I seen on fourm that it is normal but I have my doubts. My fuel gauge recently went out as well which I have a suspicion that the regulator zapped it. 

I'm quite confused to what is happening but I would like some pointers to what do you guys think is the best thing to do now. I can go back to O'Reilly's and have them check it again after I clean the grounds n contacts (The regulator insides look pretty clean but have extremely corroded screws so I gave that a clean, sanded some paint off my mounting point for better contact and cleaned up the screws), or I can replace the battery but I am worried that it's going to be zapped again. Or I can replace the alternator with an internal regulator version but I really don't have money for that currently. 

TLDR: My ammeter is jumping and has been for a while (I think I always had it) when idling. My fuel gauge recently started freaking out, and today I had a weak starter due to the battery being bad and relatively new. 

Please let me know what is the best way to proceed, thank lads!

Thanks (and yes I searched first)

Anyway. My VE table and engine was seemingly still going lean the moment boost hit. Table kept slowly increasing fuel till it hit 255

I then upped fuel pressure from 37 to 43 in hopes to get some extra CC's out of them thinking that's the issue. I changed required fuel  in tuner studio. Original CC setting for injectors was 260 and I upped it to 295. Tried tuning it that way. Obviously autotune leaned things out and then started to richen up the boost area again.  Cells Starting at 120 and now we are at 166. Still seemingly going lean. Injectors must be out of flow? It's just odd because I'm at 2psi of boost at that point and the stock turbo was pushing 12-13 psi. Interesting that just the size of the compressor housing is changing afr that much? 

I believe I know my answer is getting maybe the 440 CC injectors from Godzilla

Just wanted to get some other opinions. Maybe I'm missing something. I was hoping to run lower boost maybe 17psi max and keep the stock injectors for now. 

I will also add in I did a quick table generator, it was maxed out Rich at the bottom (255)and close to that rich under boost. Maybe I'm the 40's everywhere else. It clearly was a bit too lean driving around in the 40's on the ve table but once it hit boost that was the fastest the cars been in a while. 

So where I'm currently at is maybe with the added fuel pressure I can bump my VE Table up in the 200's and it might be somewhat drivable under boost. If that's not the case I think I need injector upgrades? Let me know your guys thoughts. Thankyou.

Stock injectors and fuel rail

240sx throttle body

255lph walbro

Trigger wheel

Ms2

Lc2 wideband

He351 ported and enlarged wastegate

Custom adjustable wastegate set top open 5mm at 16psi

3 inch exhaust