Walter Moore

The combustion chamber is smaller than the later heads, in part because the engine was smaller. Some people also talk about the head being a "quench" design, but I have never been able to track down what that means, or why it is a good thing. Apparently if you are building a 2.8L full race motor for racing gas you can get crazy compression ratios with the E31. In a stock L24 the E31 gives you around 9.5:1 or something like that. The down side, besides the valves being smaller than on the L26 or L28 heads is that the intake valve seats were brass, and didn't hold up well. When the intake seats go bad you have to have them cut out, and then you have to replace both the intake valves and seats with larger L28 intake valves. (Not that anyone minds, but the cost is higher than reworking later heads because there is more labor and parts.) If you install the larger exhaust valves, you have to either use it exclusively on an L28 motor, or on either a L24 or L26 you have to "eyebrow" the cylinder walls to create clearance for the valves. (Which seems like it ought to lower the compression ratio.) If you have the head in a fully rebuilt condition, with larger valves ready to install it might be desirable. Otherwise it is pretty much just a core.

Do you know how it sounded in the original car? I ask that because frankly the stereos in the Hyundais that I have rented in the past year or two were miserable.

Indeed, happy Thanksgiving! (Is it snowing up there yet?) ;-)

Plugged fuel injectors actually will improve fuel milage on the highway. Two plugged injectors turn the 6 into a 4. City milage may suffer, and it won't get out of its own way... But many years ago I bought a 6 cylinder Volvo that ran really bad. I drive it that way for weeks, until I gave up and took it to a mechanic who discovered two plugged injectors. It ran a lot better after the fix, and actually did use nearly 50% more gas. (OK, maybe 25%-30%)

I have never taken my car to a dyno, so I don't know what HP it has. For reference on the spark knock, I have modified the S120 distributor on my car to restrict the vacuum advance to 17 degrees. The setup is 10 static, 17 centrifugal, and 17 vacuum. This takes me to 44 degrees total advance at around 3k rpm when the vacuum advance is engaged. (Generally only in 5th on the interstate at light throttle.) I have to run 93 octane gas or else I get spark knock. You can confirm your total advance with a "dial-back" timing light. I bought one at NAPA and it is a really great tool. Using one you can discover all kinds of things about the timing curve of your distributor.

Apparently someone is restoring the car that won the East Africa Safari Rally in 1970 and 1973: Club to restore amazeballs Datsun Safari Rally Z - Autoblog Not much more than a mention, but interesting.

First of all, download the distributor information table in this thread: http://www.classiczcars.com/forums/electrical-s30/34192-280zx-distributor-advance-curve-reference.html If you are running a U.S. specification points type distributor, the correct static timing is NOT 10! it is 5 for 1970 - 1972 and 7 for 1973. If you are running it at 12, even without a vacuum advance, you will have spark knock above 3000 RPM. And this will rob you of the power you seek. I made the same mistake early on with my car also The knock will sound like buzzing because of the engine speed, not the clatter you would expect at lower speeds.

All that matters is: do you like it?

My stock sway bar pulled through the frame a couple of year ago. The problem is that there is an internal stiffener bracket that ties the sway bar mount on the bottom of the frame rail to the side of the rail. Like everything else on the car this internal bracket rusts out leaving the sway bar mounted only the the lower side of the frame rail, which isn't strong enough to take the load. I added "special" frame reinforcements of my own design, which I wouldn't necessarily recommend to others. Then I put the MSA front and rear sway bar kit on the car... I really like the result. But the Bad Dog parts would work, if you could weld.

Hello.

It looks like once again Nissan is following the pack, not leading it. Regretably, turbo 4s have become the default "performance" engine choice for small cars. Ford, Hyundai, G.M. and others have put cars out in the past year or two where they are slapping a turbo on an undersized 4 to try to make it "feel" like a 6. Now Nissan is trying to catchup. Personally, I have zero interest in being "weaned" off of the 6 cylinder engine. I don't care if it has 400 hp, I will not buy another car with a 4 cylinder engine, turbo or not. As a result of needing to be able to haul our granddaughters around, this spring I traded my V6 truck for an old Mercury with a V8, meaning that my Z is the only 6 we have in the house. Both of our daily drivers now have a V8. I made it through the last iteration of the turbo 4 madness without owning one. I will not give in this time either.

"Cheapskate Paint Job" Are you talking about my car again? I tried the roller approach. It didn't work for me because I couldn't get the paint thinned the same on any two batches. I ended up putting it on full strength with a brush, wet sanding between coats, and then buffing the car at the end. I used Valspar tractor paint (mixed a couple of colors to get the shade that I wanted.) I don't recomend this method if you ever intend to put the car in a show of any kind. Unless you are absolutely magical with wet sanding it will always look like a cheap paint job. Also the water will carry the paint EVERYWHERE, so be sure to paint the engine compartment the same color as the car, and plan on replacing every single exterior gasket and flap that is in place when you do the paint. In fact, do this BEFORE you finish the interior. (When I say that the paint will go everywhere, I mean the paint will go everywhere.) Oh, and another word of caution: Of course you will not be able to add hardener to the paint unless you mix very small quantities at any given time. But without hardener it will take a full week or more for the paint to be solid enough to sand. If you sand it too soon it will just ball up and roll off. But no matter how exhausted you get, do not put off the rubbing compound step for more than a month or two, or the paint will get too hard to work properly. I have continuous issues with rock chips. I don't know if that is due to not using hardener, or just a fact of life with all paint. At least the way I painted my car it isn't hard to fix a rock chip. I have more than a gallon of the paint at home, and plenty of brushes...

From your description I assume that your friend had the Borg Warner 5 speed from a 280ZX Turbo. I had heard that was a really strong transmission. If he broke one of those I am not sure what he needs...

Looks like a great parts car...

You could have fuel evaporating from the lines between the pump and the carbs, as well as from the float bowls. When you try to start the car the pump has to fill the lines, and the bowls. Oh, and the fuel pump operates off on an eccentric on the cam, which turns 1/2 the speed of the motor. More volume = more cranking.

I don't see how ignition failure could only affect the front three cylinders, or cause the engine to backfire through the intake. That sounds more like a valve timing issue (which would also not affect only half the engine...) or a problem with the front carb. (Which would affect the vaccum advance by the way.)

I don't have the money, or particularly like roadsters. But I agree. A turbo charged, inter-cooled Z in decent shape is easily worth that price. And really, this one doesn't look that bad.

Generally there are very few, if any S30s left in junk yards north of the Ohio river. The rust monster eats everything that is over about 10 years old.

Good luck in your quest to avoid buying Chinese made "stuff". I needed a drill press a few years back, so I went to every store in central Indiana looking at drill presses. Every one was made in China. I could buy a really expensive Chinese drill press, or a Harbor Freight Chinese drill press those are the options. I ended up buying the top of the line HF unit, and it has held up fine to my limited use. My experience has been similar on every item that I have researched. The "good" tools are made in Mexico. The Cheap ones in China. Personally, I am a skeptic on the claim that the parts store alternators and starting motors are somehow made with fewer windings. Every rebuilt unit that I have ever purchased from Advance Auto, O'Reily, or AutoZone came in a case that said Hitachi, Delco, or some other OEM brand. What fails are the diodes, brushes, or bearings. They aren't re-wound during the rebuild process. Now whether or not they fully test the windings before they replace the worn parts, that is a valid question. A couple of years ago I had to replace the starter in my Chevy truck. None of the parts stores sold a rebuilt unit for it. The starter that all four of the local parts stores carried was a brand new Remy brand unit, which is the OEM part. (Made in Mexico, just like the part at the G.M. dealers.) That being said, I would much rather have a brand new Nissan part than a rebuilt part of questionable origins. However, I don't always have the time, or the money to go that route, especially since the closest Nissan dealer is over an hour round trip from my house. I have had trouble with radiators from parts stores. Even when they don't leak, they often are missing cores. Generally for a radiator the best bet is to take it to a reputable radiator shop. They don't charge that much really, and normally the end result is much better.

Side to side play indicates bad bearings. I am not sure that 1/8th of an inch would hurt anything, but if it is a stock 78 distributor, which I think may have had a single pickup, it might cause a problem with misfires. By the way, isn't the control module on that car bolted to the fender instead of on the distributor (aka the S130 style)?

I didn't see any engine compartment pictures of the red 71, but the yellow one clearly has round-top carbs. It does have "aftermarket" seat covers however...

Avast is (or at least was when I had a Windows machine) pretty reliable. If someone here has an email address for the admins on Hybrid Z it would be worth a shout.

The show is this weekend. I will be driving to the hotel on Saturday morning (I hope). Is anyone else from this site planning on being there? I love to be able to associate names (or at least handles) with faces.

With narrow wheels it might be sufficient. Be sure to split the weight with 1/2 on each side of the wheel. (curb side and car side at the same angle.) The wider the wheel, the less effective this tool we be. It cannot detect couple imbalance. (mathematically the vector difference of the planes) Couple is significantly less important on narrow wheels because the wheel width is its primary leverage.

Ah the joy of reassembly... I remember it well. Good Luck and God's speed.