So, I did it!

Some of you may have seen my intro thread, if not: Hi! I'm Thunderlane! And I just did what many people would describe as "a mistake", but I describe as "awesome"! I bought a Datsun 260Z with an L28 swap! It's lowered (on cut springs, so that is NOT a good thing) and it was in desperate need of a loving owner! But now it has one: Thunderlane!









The body is rough, but it runs, when you spray fuel into the carburetors! The only problem was that it needed a new fuel pump (it also got new tires and a new battery). The previous owner had installed a fuel pump suitable for a L28E, and the carbs were not happy with 30psi. So, I switched it out for a more suitable 4psi unit. Unfortunately, when I located the wire that was SUPPOSED to run the fuel pump, it wasn't live (which might explain why the EFI Fuel Pump was being powered by a switched wire running from the battery, through the cockpit, and through one of the tail lights, with about 5 splices and not a single connector to be found). Unable to diagnose the problem with the wiring, I ran the existing wire through the fender and, using solid connections and proper hardware, mounted the new pump by the tank. It was at this point the engine wouldn't turn over, despite it cranking strong. Concerned that we weren't getting fuel to the engine, I disconnected the fuel line and discovered that I was getting an ample flow of fuel to the carburetors, but it went from being fresh gas to being dirty brown, but there was no moisture in it.



Should I drop the tank and flush it with cleaner? I'm not sure, but I don't think an engine is going to run on dirty gas. Otherwise, what other problems might be preventing me from getting her running?

assuming this was a carb'd 260z as most of them were, they had a manual pump. They did have wiring in place for electric it doesn't have a relay and isn't wired up. Easy fix either way. You might want to get a manual fuel pressure regulator to turn the pressure down a bit more, the floats on the su's don't seem to be able to take more than 2.5-3 psi. If you are running dgv's or other maybe you can run 4 psi? Fuel tank rus is a big problem with these cars, it's not a bad idea to drop the tank and have it cleaned and sealed. Also a good idea to open up the fuel bowls on the carbs and make sure there isn't any gunk lurking inside and that the fuel bowl to carb fuel line is clear.

I'll pick up the Fuel Pressure Regulator tomorrow when I go to NAPA to pick up the lugs I ordered for my ye olde mag wheels. I'm going to spend the day working on the car with my cousin (and going to check out a '83 Celica that he wants to buy). The goal is to clean out the carbs and gas tank, make sure that the lines are clean by running fuel through them, install the pressure regulator and get the car running.

Now, normally a build thread wouldn't feature such a mundane and unexciting update, but I felt I might as well include that information since I'm going to ask a question. Now, maybe my brain is fried from my mind numbing day-job and I'm just not looking in the right place, but try as I might, I cannot find the stock horsepower/torque figures for an L28 running twin SU carburetors. Does anyone reading this know of such numbers so that I might have a baseline? I don't plan on doing power upgrades anytime in the near future, since the suspension and chassis are where money should go first, but it would be good to know.

Does anyone have such information?

You can't find it because it doesn't exist. The l28 came only with injection and to confound things there were a few flavors of L28, dished or flat top pistons (F54 had the flat tops would offer the highest compression but came only with the Higher volume linered P79 head) and then there were 3 different heads used (the N42 being the most desirable for it's large valves and small combustion area, the n47 is nearly identical but has linered exhaust runners which restrict exhaust flow, and the aforementioned p79 with larger volume and linered exhaust runners). Truthfully the carbs should not change the hp output at least not by a significant amount, honestly the stock injection might offer a couple more ponies at the long end of the rpm range compared to the su's which tend to get overly rich at the high end. So you can figure the car makes somewhere in the 100-120 whp range unless someone spent some time tweaking it for more. and if you toss a cam and triples at it with the right head block combo you can get 180 whp range, or you can swap for the L28et, add an intercooler, boost controller and get around 300whp before the head bolt head gasket, fuel pump, turbo , injectors, and ecu all need to be upgraded, then the cast pistons will let go and you can upgrade to custom forged units and the sky is the limit.

PLEASE tell me you have all four of those front wheels.

Those MUST be on that car.

AZhitman wrote:PLEASE tell me you have all four of those front wheels.

Those MUST be on that car.

Believe it or not, I actually DO have all four of those wheels (3 on the car in that pic, the fourth in the cockpit). They've all got brand new Falkens mounted on them now, and I'm just waiting for my M12 x 125 Mag Wheel Lug nuts to get here, because NOBODY IN ALBUQUERQUE CARRIES THEM. After that, I can do a proper oil change (Yes, I do have to wait for the lugnuts. The car is so low that I can't jack up more than one end at a time.)

But, I GOT IT RUNNING, although it needs new oil, oil filter and spark plugs. And then, I can take it for a short test drive to make sure the brakes are good. After that, and a quick photoshoot, she's going back into the garage to get a new windshield, to have her inner door mechanisms rebuilt, and to have weather stripping put in the doors.

Now, whilst I'm here I must ask another question. There are a couple of rust spots in the floor, one of which is on the seat mount. When repairing these faults, will simply any piece of automotive metal do to replace the afflicted areas (which are quite small), or should I seek out a specific type?

When you go to do the door weatherstripping, make sure you use the proper stuff. MSA carries a set that fits, but the stuff from Precision will leave your doors difficult to close.

Once you start on that, I'll give you a little "trick" to help your doors close and latch like they did when brand new... Old Z guy here in town showed me, and it's a cool, simple fix.

As far as metal to repair rust areas, if you're going to do a "cut and weld" replacement, I like to use metal from a similar car. When I restored our '72 Z, the patch panels were made from a bent-up Z hood.

Update time!

So, I was taking the car out for another test drive today (this time to explore how thoroughly the shock absorbers were cactused) when I noticed that there was smoke coming from a small filter coming out of the rocker cover. This worried me and after a small bit of research on my lunch break, I discovered that this filter was attached to the crank case breather. A tiny more but of research to figure out what the hell that meant taught me that this was supposed to be connected to the intake of an L28, but that some people put a little filter on so it would look cool, in exchange for filling the inside of your car with fumes. This also explained why I have 2 hoses, one coming out of each carburetor, that go to absolutely nothing. A bit of basic logic and measuring, I figured that these two hoses must connect to that pipe instead of the filter.

But, I don't know exactly what I'm doing, so I thought I would check with you all since, as my friend says: "The guys at NICOClub could tell you how to build an S30Z from scratch." So, is this supposed to be connected? I'll update this post with a picture tomorrow, but if someone can let me know based on my description, that'd help!

Pics would help, but if there are pipes coming from the carbs that are connected to "nothing", they could well be overflows (in case the floats get stuck). You DON'T want those connected to your valve cover port.

The port on the V/C is a PCV (Positive Crankcase Ventilation) port. It should be connected to the air cleaner port, so that it creates a slight vacuum and pulls fumes out of the top end, into the intake, and burns it off.

However, if your engine has a lot of blowby (oil past the piston rings), you're probably better off venting to atmosphere. NOW, that doesn't mean that little ricer filter on the valve cover is good. In fact, it's lame. Get a length of heater hose, run it from the valve cover to someplace else (mine is tucked between the trans and trans tunnel), and let the fumes go out there, rather than in your car.

If you really wanted to get fancy, you could put that stupid little filter on the end of that hose, to keep weasels and gnomes from crawling up the hose.

Shoot us some pics. Ready, GO!

BACK!

After a long hiatus from using the internet for much more than streaming video, Thunderlane and his 260Z are back with a project update and indeed another plea for help.

First: The good news! My Z is running strong as ever, she has completely rebuilt brakes, suspension, and she's been stripped of the awful spray paint and been re-primered, and is awaiting body work (pictures to come). She's also had some detail work done to various trim pieces, and I have a new dash cover to replace her old, cracked one.

The bad news! I have lost most of my hair thanks to a bloody electrical problem! I have no gauges or turn signals. I've replaced the flasher unit and the voltage regulator, gone through all the wiring with a fine toothed comb and STILL cannot get anything. When I replaced the voltage regulator, the gauges APPEARED to work. I felt victorious! But then, I suffered a crushing defeat when, the next day, when I went to re-install the dash, the gauges failed to work again. And now, to prevent the immense frustration of this wizard's puzzle called "electricity" from making me go postal in the drive-thru at work, I come on hands and knees seeking the grace and wisdom of NICOClub, yet again.

So, a summary of symptoms:

Fuse #3 blows the moment the key is switched to the ON position
All gauges with the exception of the speedometer fail to activate upon ignition
The turn signals fail to activate, yet, the hazards work just fine, as do the brake, running and reversing lights
Thunderlane is slowly losing his mind

If anyone has encountered a similar problem, PLEASE let me know how you solved the issue! Heck, even a strong feeling would be awesome, because I am seriously running out of steam on this part of the project.

Suggestion: Less streaming video, more reading old Z threads here.

Common issue, so no more hair-pulling.

The light / turn signal switch on the Z is crap - they are almost universally bad, unless they've been rebuilt. If you remove it and take it apart, it's pretty self-explanatory. http://www.kamikazeracing.org/dl/ZTech/ ... switch.pdf

Also, while you're cursing the electrical system, now is a good time to set the headlights up to work with a relay. The stock design sends ALL 12v through a small contact in the column switch, which is silly. You'll nearly double your light output if you do this correctly, and save yourself some hassles later. http://www.zhome.com/DaveRelay/DavesHeadlightRelay.htm

Have you pulled the diagrams from http://www.datsunservicemanual.com for your car?

On mine, I had a loose wire to a rear turn signal, inside the RR fender, in an unreachable location. Common, I've heard. Also, you may have a short at the bulb socket in one of the lights or markers, so don't ignore those.

Would a faulty switch really kill everything on that circuit? Wow, I'll definitely be rebuilding mine tomorrow, as well as replacing all of my bulbs. I do have to ask, though, what else could it be? If these two processes fail, what is one to do to restore life to their beautiful Japanese gir- erm... sportscar? Would the next thing be just running through my wiring again and again until I find the issue?

Also, which would be the exhaust to go for: a twice pipe or a cannon? That is the next project and I need to order parts soon, so I figured I'd ask for y'all's opinion.

Thanks for the ideas!

Thunderlane wrote:Would the next thing be just running through my wiring again and again until I find the issue?

There you go. Like I said, mine was almost impossible to find, so take your time - take notes, don't skip any wires, and be thorough. Continuity from terminal to terminal is going to be key.

Thunderlane wrote:Also, which would be the exhaust to go for: a twice pipe or a cannon? That is the next project and I need to order parts soon, so I figured I'd ask for y'all's opinion.

I'm a fan of a subtle, 2.5 - 3" chrome tip on a Z. Unless you can find an old Ansa dual-tip, less is more.

Okay, update!

So, I disassembled and cleaned the headlight switch and the combination switch, which didn't help my situation. Now, it would seem that when I replaced the voltage regulator with a fresh one, that was a step in the right direction, but that victory was quickly snatched from me. Would a short in this circuit (ie. Me testing the turn signals when the switch was still all carbon-y, after installing a new one) fry the voltage regulator, or am I just grasping at straws?

Either way, my combination switch and headlight switch is now free of carbon buildup!

I am now officially trying to fast track these repairs, since seeing that shiny new dash cover just WAITING to go over the old cracked dash is really getting me excited to drive my car after it's winter slumber. But I can't do that without gauges and turn signals, damnit!

IMPORTANT UPDATE!

So, after a night of cleaning, masking, painting, cutting, soldering and crimping, I got nowhere! (But the previously crappy trim on my driver's side door is lookin' sharp in flat black) But, this update isn't exactly about that! Yesterday, my father and I were doing some voltage tests and we noticed that we were getting slightly lower voltages than we had in previous tests (Around 11.4) so we decided to test the alternator... And the alternator is cactus! So, I'll be ordering parts for a 280zx alternator swap this evening and hopefully I'll have them by the end of the week. One can only hope!

But, my query is, would a faulty alternator (Say that 5 times fast) cause problems with my voltage regulator, which is tied into the same circuit as my gauges and turn signals? I've seen a couple cases on various forums online where people had this same problem (dead gauges and no indicators), but it was resolved after replacing their alternator. Is this even possible, or am I just really hoping that I don't have to check the wiring for the 11th time?

Either way, the alternator is shot, so that has become ANOTHER priority. Until I can get that fixed, I'll be doing some trim work, general cleaning, parts ordering and RESEARCH. I just gained access to a book all about auto wiring, so I will be tucking into that quite soon. But, for now, I must rest! I've been huffing paint fumes for the past 4 hours and have a killer headache... But damn that driver's side looks good! (Pics to come)

The 280ZX alternator most probably has an internal regulator and will eliminate the need for the OEM regulator. You will have to connect a sense wire from the internal regulator to some voltage reference - the plus terminal of the battery if you don't have a big load elsewhere.

Several modern alternators are a good swap into a Z. I think most of my Datsuns are converted to GM 105A alternators.

See this thread: http://czot.org/forum/showthread.php?20 ... Alternator