LeonV

I suppose my phrasing was a bit awkward. Retarded timing at idle, and advanced everywhere else has a stabilizing effect on idle speed. But now that I think about it, the effect isn't really there when using a distributor. There could be some dynamics involving how much the throttle must be open under retarded/advanced timing, but I think these are all secondary effects and not really noticeable. It's more beneficial for EFI with programmable spark maps.

Nice, that's a car from the New Years ("Anti-Football") classic car run I went on! I remember seeing that Alfa (among many others), along with an eye-shattering amount of car porn! Too bad my camera sucks, and I took few pictures because I was going on 2.5hrs of sleep... I'll just leave a few teasers, from our mini-convoy:

I've loosened the crank bolt on a block with a method similar to John's. I cut up some extra roll bar padding and put it on top of a cylinder. Then I just put the head back on and tightened 4 used head bolts around that cylinder, not to spec but just tight enough for the head not to be loose. Get a big bar on there and you're done! Of course, this is if you have access to a head and have your old bolts laying around.

I agree that there is less NOx emissions at idle than with the engine loaded, but you will see a reduction in NOx through retarded timing. Even if you have a stable idle, retarding the timing will increase exhaust temperatures which then burns up more unburned HC coming from the combustion chamber. At this point, we're getting into the finer details. Point being, for the OP, is that certain emissions will be reduced and off-idle torque will jump making take-offs easier (and stalling harder, unless you let off the throttle).

Good question! "Ported vacuum" is used for emissions reduction, among other things. Retarded spark timing reduces peak cylinder pressures, which reduces peak combustion temperatures. This makes for a reduction in NOx emissions, since NOx is dependent on combustion temperature. Conversely, exhaust temperature increases with retarded timing, thus a reduction in unburned HC is also realized. A side-benefit that I see is stall protection. Since the vacuum advance quickly activates as the throttle is cracked open, off idle engine torque is considerably more than at idle. This gives the driver an effective buffer, or aid, in getting the car going from a stop. This can be seen in modern spark maps as well. Also, overly-advanced idle timing is more prone to misfire. Taking a stock '72 240Z, with base timing at 17deg and max vac advance giving another 11deg, that's 28deg of spark advance at idle!

And people say that triples are a pain! As much as I'd like to see the issue resolved, I say just get yourself some Webers or Mikunis already, you won't regret it!

As far as the spacers, those are for the front crossmember mounting points.

Good point. This is one of the reasons why suspension fasteners must be torqued with the car fully laden. If someone torqued the suspension down with the wheels in the air, problems like this one can arise.

You lucky guy!

Yes, it's real. It's CJBrian's from hybridZ. If he was local, that would have been in my garage weeks ago.

FWIW, you can get a close approximation that spring's rate with a spring rate calculation. k = Gd4/8nD3 Where, k = spring rate (lb/in) G = Shear Modulus (about 11.5 X 106 lb/in2 for spring steel) d = wire diameter (in) n = # of active coils (total coils - 2) for that spring D = average coil diameter (in) That should get you close.

Dave and others are spot on. If you did not diagnose a problem with the engine which dictates a rebuild, then you definitely should not assume that it needs one. You will be way ahead if you take the steps to diagnose any problems with the engine before you go digging into it. It's a good idea to replace the water pump if you don't know the history of the engine, and that's a simple/cheap job, especially compared to a full-on rebuild. I would set valve lash and check compression. If your results are good, then put in a new water pump, intake/exhaust gasket, along with any other maintenance items that need attention (gaskets, hoses, fan belt & clutch, etc.), and go drive the thing!

Now those are funny!

If by that you mean disagreeing with thoughtless statements, then yes, that's normal.

It sure didn't seem like it from your first post:

Seems like you're then one without a clue...

BTW, power is very much a product of fuel delivery method as well, since different fuel delivery methods have their own inherent pros and cons. Carburetors use venturis, this is an inherent pressure drop caused by the fuel delivery method of any carb'd engine. Equally sized ITBs will make more power. Port fuel injection injects fuel essentially at the valve, thus there is much less opportunity for the injected fuel to homogeneously mix with the air. Less homogeneous mix equals a less efficient burn which equals less power. Not as big of a deal as a venturi, but it's still there. This is why high-performance (read: race, "not for highway use") engines inject before the throttle body, not at the valve. These things all have to do with how fuel is introduced into the intake/engine, thus fuel delivery very much affects HP. In the case of carburetors, the fuel delivery method directly affects airflow. In the case of port injection, the fuel delivery method affects the way the mixture is burned. The causality is the same for direct or TB injection. This can go on for any system, so making a generalization such as HP not being a product of fuel delivery is incorrect and at best a gross oversimplification.

Right. I'll quote myself, with some emphasis added this time: Also, MS can be (and often is) used to go to distributor-less ignition. A completely tunable timing curve will give you more power compared to using a distributor, because of total spark map control and essentially zero spark scatter.

The last two headers mentioned in this thread are just MSA headers. You can get them way cheaper from MSA themselves. Link Nissan Motorsports still advertises their header, but as far as I know, you can't get those anymore.

Personally, I would've passed on that car anyway. The search for the right car takes a while, so if you have patience and know what you want, it will happen eventually. Good luck!

Performance will increase if the spark and fuel maps are done adequately. Removing the restriction of the AFM (not needed with MAP based EFI, aka "speed-density") gives you inherent gains in performance. All aspects of engine performance will be better, again, if done correctly.

Just install it inside the old ECU case and you're good to go!

That is baffling logic, John. You mean changing spark plugs and putting in a new fuel pump won't solve everything?

Thank you, that's exactly what I'm saying! Relax, people.

A danger? By touching the car when stopped? Gimme a break. If, of all things, you're scared that someone will touch your car while you're driving then by all means just keep it in the garage. Were you at the anti-football run? I was there in my Z along with a couple other Zs and a Skyline! I agree that some cyclists can be complete morons (as can any other person), but that doesn't mean that we should morons back to them. I too get annoyed when they hog the road and feel all self-righteous, but I'm not going to shoot them or run them off the road. I've seen a guy almost run a cyclist off the road, it's stupidity at its finest. Sounds like some people just need to take a deep breath and relax...