240260280z

In Physics F=ma In Datsuns F=a/m where F is Fun, m is weight and a is proportional to motor's power. Here are some car comparisons I just stuck in a quick table:

Not sure if any of you saw this chopped Z idea from many years ago. Here is a n updated chronological page: "Mechanix Menace": An LS7-motivated, chopped and heavily modified 1973 Datsun 240Z

Captain Obvious taught me a cool trick for orientation of parts like the breaker plates....when disassembling, put them on a string or wire through the centre and tie it off. Doing the work over a magnetic bowl to catch the ball bearings would also be wise.

Theory of combos for S30 but it matches Nigel's empirical observations above: http://www.classiczcars.com/forums/wheels-tires-brakes-s30/48908-master-caliper-brake-combinations-ratio-changes.html

check your condensers. They can fail intermittently with heat and some may be in the tach circuit.

I think they were $275 CAD here and I picked up at the local Nissan dealer. Try those part numbers at a few of the Nissan shops in Miami. You should be able to eliminate shipping.

Looks like an unrestored Japanese Zero I just saw. Keep the momentum!

I bought one ~5 or 6 years ago. I assumed they would still have stock.

Englishman in France

I agree. There is enough info on this site to tune them as well as how to inspect to ensure they are working properly and not binding. SU's are fairly simple.... a throttle valve (like on any car) and a fuel metering part (a needle and a hole) The key points are: 0. Fuel pressure is ~ 3.5 to 4psi 1. Mechanical linkage from pedal to throttle valves works smoothly 2. Each carb's throtle valve rests on its stop screw at idle 3. Air flow at idle is balanced by adjusting stop screws 4. Pistons move up and down easily and carbs are clean 5. Needles protrude equally from each piston. 6. Chokes move freely and jets don't bind when they move up and down (you can probably disconnect choke cables in Panama 7. No air leaks in intake plenum 8. Jets are ~ 2.5 turns down and holes are not ovaled 9. Needles are the same, are straight and are not worn 10. Air flows the same into each carb at 3000 rpm 11. Front 3 plugs look the same (front carb output check) 12. Back 3 plugs look the same (back carb output check) 13. All 6 plugs look the same (engine balance) 14. The car runs equally as poor when you lift the front carb piston (running on back carb) as when you lift the rear carb piston (running on front carb) 15. Fuel bowl levels are the same and ~19mm down from rim. Ensure timing, valves, gaskets are in good form. I wish I could have met you when I was in Panama in Dec. it would have been fun to tune your car.

Hey Joe, You can get fenders from Nissan. They fit well.

• Further, it can be taken that the main affects the total range while the air corrector has more and more say as the revs rise, though at no time is its effect negligible. • In general, it can be said that large main jets with large air jets give a setting rich in the lower and middle range, while small mains with small air jets achieve the opposite. • A very large pump jet or high-speed bleed can enrichen the top-end mixture to such an extent that a larger air corrector may be needed in order to prevent over-richness. This may, of course, in certain contexts achieve the desired mixture slope but, on the whole, large pump jets or opened-out high-speed bleeds making up for the main system weakening off too much in the top range cannot be recommended. • Using the same venturi in a 40 vs. 45, the pressure experienced by the charge will increase more in the larger 45 after passing through the venturi and promote more precipitation of fuel from the charge. From the great Passini So you can have many combinations of main and air that will work for you but having the larger orifice combos are not target to aim for. Likewise you can choke a 40mm and 45mm to the same 30mm venturi but when the fuel/air charge exits the 30mm venturi, it experiences a bigger pressure increase in the bigger 45mm carb throat than in the 40mm carb throat that can cause more fuel to precipitate. I have been studying carbs for the past few years and here is where my tuning process has currently evolved to: Make sure valves, vacuum/vacuum leaks, fuel pressure, electrical, rings, sealing gaskets, etc. are all in good order. Ensure all carbs are the same with same internal components and are in good order. Step A: SET Timing set ~ 15 to 20 at idle set ~ 34-40 at max Step B: Synchronize Mechanical Linkage inspect and remove all slop ensure throttle valves open fully and that accelerator pedal stop is adjusted correctly set all idle stops for same air flow at idle (800-1000rpm) set 3000rpm air flow to be the same Step C: Disable Cold start system (choke) assembly ensure cold start plungers are closed and sealing. disable choke cable mechanical Step D: SET Progression and Fuel Bowl Level get an a/f wideband O2 meter remove main jet assemblies and close off jet to accelerator pump (at bottom of fuel bowl. A metric bolt will do it) balance all carb's idle screw mixtures and air flow to get the motor to run evenly note mechanically where the throttle valves and foot pedal are just exposing the progression holes (cruise) try to drive around at this "cruise" point in different gears and note the a/f ratio in each gear adjust the fuel level up if you are running lean at cruise (aim for ~ 14-15 at cruise) adjust fuel level down if you are running rich at cruise (aim for ~ 14-15 at cruise) repeat 2 to 7 above until you are happy (check air flow balance and timing). NOTE If you can't get the A/F right at nominal fuel levels then change the idle jets to leaner or richer and repeat steps 3 to 8 Step E: SET Idle this is partially done in step 8 above adjust idle enrichment screw to where you want the idle to be. Most find richer idles ~ 12.5 to 13.5 to be a sweet spot but it can be stinky. If 13.5 to 14.5 works for you then that may be better. re-check A/F at cruise to ensure the idle progression has not impacted the cruise a/f too much. If it has then change the idle jet accordingly and repeat all of the above. Step F: SET Mains reinstall main jets make runs on a long gentle incline in all gears from 3000 rpm to 5000 rpm recording the a/f mixture at each 1000 rpm increment change main jet as required to ensure correct richness between 3000-5000 rpm Target would be 12.5 to 13.5 Once the main jet is selected, repeat step 2 from 3000 to 6500 and note the a/f ratio at the higher end. Change main air corrector accordingly if it starts to go too rich or too lean as you approach 6500. Same target of 12.5 to 13.5 should be aimed for Recheck cruise to ensure it is not too rich. The fuel height affects were the mains come in. If the fuel is too high, the mains will be in at cruise and richen the mixture. If the fuel height is too low then the mains will come in too late and you will get a lean spot in the transition. If you can not get an appropriate a/f at cruise (mains in early and too rich) then go back to step D above and lower the fuel level, change the idle jets and repeat the all the fun Step F: SET Accelerator Pumps reinstall accelerator jet at bottom of fuel bowl make runs on a long gentle incline and punch the gas to accelerate violently and note a/F ratio spikes when you hit the gas and how long it takes to stabilize repeat in all gears adjust accelerator pump jet size and fuel bowl back bleed to optimize. starting at lower accelerator jet size is best. if a lean spot from cruise to rapid WOT can not be resolved with the accelerator pump circuit then raise the fuel level and go back to the drawing board ... STEP D Have Fun. It is actually fun and iterative. A good co-pilot reading the A/F and recording in the passenger seat is a must.

That is similar to what is in the 78 wiring diagram. You can always disconnect 1 at a time to see what drops. It looks like the black FL feeds the fuel gauge and hazard light on the schematic. You can follow the wires from each fusible link then use the disconnect and multimeter testing to verify.

Here is a block diagram for an internally regulated Z and it shows the sense tapped from a downstream (of Fusible link) For convenience, when converting from external to internal regulation, I connected the yellow sense to the 12V bus wire that is downstream from the battery through the fusible link. I guess if the fusible link burned up the sense circuit would fail however I am guessing the sense wire should be fused for safety. Here is a blurb on the sense wire: 2. An "S" connection which goes as close to the positive terminal of the battery as physically possible. The "S" connection "senses" the battery voltage and this is the voltage that the regulator is tying to control. This connection has a high impedance, so it only draws only micro amps from the battery, so it can be left connected without fear of battery discharging.

Here is the 78 FSM electrical wiring diagram. Use it and a multimeter to trace. I had to do the same for my 77.

http://www.atlanticz.ca/zclub/techtips/fusiblelinks/index.html

"93.9% done"

I want you to restore my Z's! Beautiful work.

And in a region that does not freeze much.

If I'm in Poland I'll look you up! I have many Polish friends here in Nova Scotia so we should get on well. Keep throwing out questions and all of us on the forum will do our best to help.

Here is a Lada racing build with delorto side drafts that may have useful info. Here is a carb bage from the thread: http://forums.finalgear.com/post-your-car/my-lada-2107-racecar-project-5986/page-15/#post856061

The carb internals seem ok for 1.6 litre. The 50F8 idle jet could be made a bit leaner 50F11 if it runs rich at cruise. 29mm fuel height is a good initial target. The 115-F11-150 should also be ok for a starting point. The 32mm main choke could be dropped to 30 or even 28 to give you more low end. Before tuning the carb you need the cam and rocker sorted as well as measure timing. Here is a great page that goes over tuning webers: Weber DCOE triples, L28s, and Datsun Zcars

I thought Z's worked best with slightly wider track in the front? Also I read that same tire sizes are best? Any insight?

Welcome Hubert! What are the internal component sizes (jets, choke (venturi), air correctors, emulsion tube)? What is your fuel level? Do you have a way of balancing air flow? Read this to get up to speed on how side drafts work: http://www.classiczcars.com/forums/carburetors-s30/44095-understanding-weber-side-draft-carburetor-through-fictional-supposition.html

I always say that when you drive a Z for a while you can smell how fast you are going.