doradox

Do you have a service manual? What is the clutch pedal free play. Did you check the pilot bearing? Steve

Usually one would start with the basics. Be a little more specific about what you've done with regard to the pedal free play. Make sure the clutch master and slave have the correct bore sizes . Make sure the system is properly bled. When the clutch was out how exactly was it "looked at" to determine that it was ok to re-install? Was the pilot bearing checked? Steve

NGK has this to say about anti-seize: http://www.ngkplugpro.ca/content/contentfiles/pdf/NGKSP-0907-1R-Anti-SeizeonSparkPlugs.pdf Note they suggest that one use torque ANGLE if using anti-seize on a non plated, i.e. not NGK, plug. This makes sense from an engineering standpoint as this takes thread friction out of the equation. I tend to go with the engineers that design and test the product and give a reason based on sound engineering principles for following their suggestions. Steve

I think I'll side with the plug manufacturers and the vehicle OEMs on this one. Those damaged threads usually come from over torquing, dirty threads, or trying to remove plugs from a hot engine, and not from lack of lube. But if that's what you need to do who am I to say. Steve

You might want to rethink the anti-seize. The torque value in the FSM is assuming dry threads. Lubed threads will give a tighter joint for the same torque which causes higher stress on the threads and plug shell. It can also distort the spark plug shell, which can damage the ceramic insulator. Also it can change the heat transfer characteristics which effect the heat range. http://www.ngksparkplugs.com/tech_support/spark_plugs/installation/index.asp?mode=nml Steve

Actually, if you richen the mixture to account for a vacuum leak at idle, which would give you correct mixture at idle, you'll be rich everywhere else. If set the mixture correctly for everywhere else you'll be lean at idle due to the leak. Steve

Are you checking that with the vacuum advance disconnected? That sounds like an awful lot of centrifugal advance alone.

Possibly a vacuum leak. Squirt a little carb cleaner around where the intaks manifold connects to the head. If you've got a leak you'll know as soon as you hit it. Steve

Sounds normal. Maybe a little brake drag in the right wheel which would cause it to not spin when you were up on the stands. The driveshaft would have been spinning instead. When a spider gives out you go no where, and often there are lots of bad expensive sounding noises. Steve

You should plug in the stock numbers for tire/wheel size etc. This will give you the stock angle which is totally independent of wheel tire combo. Toe-in in inches will give different angles depending on wheel and tire size. Angle is the same for all wheel and tire combos. That's a reason that angle is used by your alignment folks, it takes tire size out of the equation. Steve

I'll probably get laughed off the site for this but I have a soft spot for the '72 Pinto I had '76 when I was 16. It was an ugly yellowish green I bought off the wholesale lot at Jim Click Ford in Tucson. $700. 100,000 miles already on it. It was a base model with the 1.6 liter OHV 4 and was slow as snot. But the darn thing took 36,000 miles of my abuse with hardly a whimper and I sold it a year later for $200 more than I paid for it. Yeah, it's not the most glamorous, but the darn thing was a beauty to drift. It had tons of steering lock and oversteered like crazy. The manual rack and pinion and light weight made it oh so easy to control and I tore around on the dirt roads in the foothills of Tucson imagining I was a world famous rally car driver. I year later I had a '70 Cortina with the same 1.6 liter OHV but is much higher tuned and I would have loved to have swapped. I occasionally look for one for sale but haven't seen one like mine. 1.6L, 4 speed, no hatch back. I don't imagine it would be all that much fun now which is one reason I have the Z instead but it would be cool to have one again.

Toe angle = Inverse sine of ( toe distance/outside diameter of tire) Use the same measuring units for toe and diameter. Steve

Are you sure it's on the correct side? If it were on the other side it would protect the mustache bar bushing from exhaust heat. After taking a closer look, no it wouldn't. Huh. What's behind it? Steve

If you don't have the answers then there is no way to determine the "safest" source to use short of trying them both. Watch for detonation and high coolant temps. If neither are present with either source, pick the one that runs best. Otherwise pick the one that doesn't detonate and/or run your temp up. In my experience the biggest difference will be in idle quality. Ported vacuum ( the carb port) will not give any advance at idle whereas manifold vacuum will, assuming your engine is in good enough condition to pull normal vacuum numbers. My '72 idles better and has better throttle response with manifold vacuum connected to the vac advance but my carbs are old. YMMV. Steve

I think a little more specific information might help. What shop equipment are you using i.e. tune up scope, 4 gas analyzer, etc. Is the dwell consistent across all 6 cylinders? What is the secondary voltage at idle ,2000, 4000 rpm, max voltage available at each plug? Coil oscillations look normal? What are the CO, CO2, O2, and HC readings at various rpm. What vacuum readings do you get at various rpm? What is the timing (vac advance disconnected) at 1000, 1500, 2000, 2500, 3500 rpm? Have you artificially leaned and richened the mixture and noted change in rpm. Being a Z specialty shop I am assuming you have known good parts to swap. Carbs, distributor, coil, wires, etc. These things have been tried? Was the intake replaced at some point? I know it sounds stupid but was anything accidently left in the intake ports? I typically stuff them full of rag or paper towel when working with the intake off to prevent foreign objects from getting in the ports. Steve

Since the only difference between ported and manifold vacuum is when the throttle is closed one might say that by using manifold vacuum the only time the timing curve would differ from stock is at idle or any other time the throttle is closed. So during a large majority of the time the engine is running it is using the stock timing regime. If using no vacuum advance then the only time the timing curve is the same as stock is when the engine is under a high load or at idle. Arguably a small percentage of the total time the engine runs. I would suggest that the former is the "safer" way to go. However, when you are on the gas hard both no vacuum advance or manifold vacuum advance behave exactly the same way. The whole point of vacuum advance is to advance the timing during cruising and other light loads. That's why race distributors don't use a vacuum advance. Anyway if the manifold he has won't let the vacuum advance work then he essentially has none. Which is what you suggest. So no harm done. Steve

You can use manifold vacuum just fine. The only difference between ported ( which is what you would have with stock SU carbs) and manifold vacuum is that ported vacuum is unavailable when the throttle is closed, otherwise they are the same. I don't believe the SU uses venturi vacuum for the distributor vacuum advance as that would over advance the timing at full throttle and lead to detonation. Also the vacuum port is in the wrong place for venturi vacuum. http://www.jetlink.net/~okayfine/su/troubleshooting.html Go to the bottom of the page at that link for a better explanation. Steve

I'm 50. Bought my first Z, a '73 in Tucson AZ in 1980. I had a friend, Rob Smith of RPS Performance Products that was into imports and smaller cars like I was and he bought one shortly after that. We had a lot of fun modifying and driving our cars. It's the car that took my wife and I to Las Vegas to get married. A new baby, house, and the wife not liking to drive the Z due to the triple Webers not having a choke and being a little finicky on the bottom end and I ended up selling her to a friend. The Z, not the wife. Anyway, I purchased my second Z, another 73, about ten years later and it was my daily driver for several years. I had a '75 280 for a while, basically bought to fix and sell, and an '81 280ZX that became a drivetrain donor for the '73. I ended up selling that one before moving out here to Indiana in '98. I was going to need a car that would get me back and forth from Lebanon to Purdue in West Lafayette in the snow and ice while getting my engineering degree, and I wasn't going to have a good place to store the Z for a few years, so I sold that one too. Now that I have the space, time, and money again I have my current cars, a '72, and a '72 parts car. It's like coming home again as I've spent close to 200,000 miles behind the wheel of my first 2 Zs. Steve

Guess I should have said "on my 72" blah blah....

The resistor mounts separately below the coil in it's own hole. Not in, on, or under the coil bracket. Steve

Your mechanic can quickly check your timing mark/pointer by taking out the number one spark plug, turning over the engine by hand, and stopping when he sees the piston come up to TDC. It won't be super accurate but if he was careful the marks should be within about +/- 5 degrees of indicating zero or TDC. If so, you should be good. Steve

In your first post you stated.... Have two sets of carbs been used on this new motor? You also said.. Have you actually driven the car? I ask because if the base timing is so far off the car won't rev out it should run poorly at all other rpm. Just sluggish all around. And this has me puzzled.. How did he notice a timing drop off? And what does that mean? The timing should advance as the rpm increases, if not the distributor is bad. Timing effects the vacuum signal to the carbs so fix the timing issue first then the carb issue. Steve

I would look at the things you changed if it wasn't making the noise before you did the work. It's unlikely that your wheel bearings went bad while you had the diff and control arms out. Steve

The 240SX runs a 4:10 rear end stock. If you don't have at least a 3:90 you might be a little disappointed with the gearing. Or not. I have one (240SX) and I'm not a big fan of the rpm drop in the 1-2 shift. First is just a little too low so the jump to second is a little too much IMHO. But the rest have nice spacing. With a 3:90 the 1-2 shift would be little worse, but at least first gear wouldn't run out so quick and you'd be turning a few less rpm at highway speeds. Steve

That's called the thrust angle. If the overall toe angle is still OK it won't really effect tire wear unless it's off by a lot. You were able to see it from the angle of the rear wheels so it probably is off by quite a bit. Your front wheels "automatically" steer a little one way or another to compensate. The wheels go down the road straight (with the front and rear a little offset from each other) but the body goes a little sideways. The term "dog tracking" is often used to describe that condition. We've all seen the dog that runs along with his rear end not quite following his front. Steve