rsicard

"The article was written about the generic L-Jetronic system". The L-Jetronic is a BOSCH fuel injection system! This discussion is FAR from where it needs to be. Most EFI systems have an embedded computer system wherein the fuel and ignition curves are contained in memory devices in binary form.

With the Painless kit, what was done with the turn signal, high/low beam, headlight, wiper and washer switches stalks on the steering column? I am faced with fixing up the wiring on my 71 240Z. After studying the wiring diagrams the fixup solution is not all that bad. Purchased a separate fuse panel which will be positioned where the original is but has a better capacity. Also want to update running and turn signal lamps to LED types and the turn signal and emergency flasher need to be replaced with modern types to handle the LED bulbs. Designed a rewire of the headlight circuits to add relays to take the heavy current off the stalk switches which fixes the design deficiency of the original circuits. The same needs to be done in the ignition key on circuit by adding another relay.

More modern engines have 4 valves per cylinder, dual overhead camshafts, dual camshaft CHAIN drives. The pushrod engines have LESS parts to FAIL! Latest state of the art Corvette cylinder heads are VERY if not more efficient than any other cylinder head on the market by any manufacturer. Displacement for displacement, blown or Un-blown, the pushrod engines makes the same or more power and just as or more efficient than the overhead cam engines with LESS PARTS to fail. Don't understand peoples thinking about modern engines.

How much of the "C" channel portion of the cross-member had to be cut to the rear of the member to fit the square mounting tube? The "C" section of the cross-member is spot welded at the factory to a formed and stamped plate which has a flange at the forward and rear portion of the cross-member. Would the mounting of the rack come out too far forward if the square tube was welded directly to the forward flange of an unmodified cross-member? Just wondering. Please advise. Thanks.

Jon: Trying to visualize what you are talking and showing in the photos. The cross-member is made up of a "C" channel and contoured flat plate spot welded together. Does the 1.5" square tub get welded to the forward portion of the bottom flange of the cross-member? If not, how does the square tube attach to the cross-member? Please advise. Thanks.

Pyro is right in his recommendation of a 96 to 99 vortec truck engine. The vortec block is of the generation wherein CNC machining has been used. The castings are likely more consistent than earlier blocks and the lifter bores are taller for better alignment/retention of the lifters during running. All around a much better engine block. Bore it .030 over and get a cast 3.75" stroker crank, 6" rods and SRP Pro pistons and you have a good bottom end. Use AFR heads, a good cam and appropriate induction system and you have a VERY good engine.

That looks to be the fuel vapor return from the engine compartment.

The custom made drive-shaft is a certainty.

I went with a R200 from a Turbo 300ZX. It is a Clutch Limited Slip Differential (CLSD) with 3.7 to 1 ratio. Then purchased Turbo 300ZX CV half shafts and beefy stub axles from Modern Motorsports. Shortened all 4 struts and installed adjustable coil overs and Koni adjustable shock inserts. JTR has the parts for assembling the drive shaft to the R200. Need the yoke at the back of the transmission. T56s are expensive. A T5 in good shape may be a better choice and much less expensive than a T56. I have a T56 and in retrospect a T5 would be nearly as good. The right ratios in the differential and T5 are important to the usage of the car. The more involved you get the more expensive it becomes. Cheaper for street use. Expensive for race purposes.

It's easy to see that fitting the rack to the front cross member will be difficult. I also want a good power steering rack such as that which you have purchased. I want to road race my V8 240Z and will need a sturdy rack. That is why I am interested in your efforts with this custom rack. Your approach seems to be on track by first removing the engine mounts from the stock rack. The rack mounting points and engine mounting points will have to be integrated into a custom mount which can be bolted or welded back to the original front cross member. This may be a project for a good CAD person to visualize the custom mounting point bracket.

Contact the folks a DIYAUTOTUNE.COM. Return the ECM to them for bench testing. You need someone with a good electrical/electronics, mechanical and EFI experience.

The CS144 should only need two wires. One light and one heavy gauge. The lighter one goes to a small fuse and has power on it in the key on position for alternator field excitation. The heavier one goes to the battery though a fuse or fusible link. The return for both of these wires/circuits is back through the case and engine. Best to have a heavy gauge wire from the case of the alternator back to the negative post of the battery. Then there is no question about the ground path to the negative post of the battery. Also a wire should go from the battery negative post to the body for accessories. Hope this answers the questions.

If the ammeter is jumping there may be a WEAK connection between the alternator and battery positive terminal. At idle the ammeter should go to zero charge or negative in that the battery is being drained. When the engine is revved up the ammeter should smoothly go to a charge indication after starting the engine. Some time after the engine has been started and the engine RPM has been increased for a period of time the ammeter will have a decreased indication but still a charge indication on the ammeter which means that battery is being recharged. The battery is merely a storage reservoir of electrical energy. The purpose of the alternator is to refill the battery reservoir with electrical energy after starting the engine. Then during normal driving the alternator will likely have restored the reservoir and will compensate for other electrical loads on the electrical system such as the ignition system, any lights that are on, the radio, the heater/AC blower etc etc. STRONGLY suggest installing a VOLTMETER in the dash to monitor electrical system voltage. During start a good battery should not go below 9 volts. After starting the engine at idle the voltage should bounce back to 11-12 volts. Then when the engine is revved up the alternator kicks in and the voltmeter should go above +12 volts indicating the alternator is charging the battery. Erratic reading indicate a bad alternator or POOR electrical connections be they field excitation to the alternator or heavy current wiring to the battery. Live in East Tucson. Go past DM many times and for air shows. Many retired Air Force people here as good friends. Love the noise of fighter jets overhead as this is the sound of FREEDOM. Was involved in Aviation Electronics for 38+ years. Electrical systems are EASY in comparison. Several years spent at Learjet as successful Liaison Engineer fixing MANY electrical and electronic problems on Aircraft. Also twice qualified Navy Aircrew-man aboard P2 (Sonar) and P3 (Communicator) ASW aircraft. Now a Amatuer Radio Operator with all three licenses. Attend three different radio clubs here in Tucson.

There is no advantage to the LT-1 or LSx over the Gen I Small Block Chevrolet 350. If the 350 needs to be rebuilt it costs little more to bore and stroke it to a 383 cuin. It is the cylinder heads, camshaft, pushrods, rocker arms and induction system that make the real difference. With the proper combination of upper end parts, displacement for displacement the Gen I matches the LT-1 and LSx engines. It all comes down to the performance of the components. More performance = more money.

Check the items as described. YOU WILL FIND your problem.

I have a 240Z also and have to do something with the wiring. The weaknesses in the wiring are the mechanical connections and the switches. Nissan routed heavy electrical current through the steering stalk switches for the headlights and running lights. The headlights have two fuses. One for the left headlight and one for the right headlight. That aspect of it is GOOD in that with one fuse blown both headlights DO NOT go out. The bad thing about it is the heavy electrical current for the headlights runs through the switches on the stalks on the steering column. To overcome this DESIGN DEFECT insert relays in the positive or negative side of the headlight wiring and have them controlled by the stalk switch which has to handle MUCH LESS electrical current. Then have Dave (on classiczcars.com) in Washington state rebuild the switches for you. Then the system will be BETTER than new. Also replace the running and turn signal bulbs with LED replacements from Superbrightleds.com. They may be expensive but should last much longer than incandescent bulbs. Additionally, I found BAD single contact male and female connections in the harness on the cabin side near the firewall by pealing back the wrapping on the harness. Then cut off the blade type connectors, stripped the wire, slipped on heat shrink tubing, twisted them together and soldered them with Rosin Core solder and then slid the heat shrink over the connection and shrunk them with a heat gun from Harbor Freight. The other area that may need attention is the underside of the fuse panel. Perhaps some soldering will reinforce or strengthen connection there also. All the above is easier than replacing all the harnesses. Just some suggestions.

The field connection on the alternator will have a lighter gauge wire with +12v on it when the ignition key is in the "RUN" position. The Red/White should be the heavier gauge wire that connects to the heavy post on the alternator. The Red/White wire is carrying the heavy charging current for the battery through the ammeter back to the battery. This is the wire which must be a very low resistance connection between the alternator and the battery positive connection.

KTM: Thank you for spelling out the TRUTH. Hopefully the other folks on this forum will read this post and take heed. As long as money is being put into the drive train of a 240, 260 or 280Z, the best bang for the buck without a doubt is the Small Block Chevrolet (SBC) V8 engine. Several GM transmissions fit behind the SBC V8's. The other concerns are what the car is going to be used i.e. race, drag or street. The SBC can be modified to output 500+ HP normally aspirated. With turbos or superchargers 800 to 1000 HP can be achieved WITHOUT winding it up to 8000 RPM. Overhead cam engines just have more moving parts to fail versus well proven push-rod engine with a lesser amount of moving parts.

First set the Multimeter on the resistance mode. Short the two meter leads together and it should read ZERO ohms (meter check). Then connect one lead to the heavy post on the alternator and the other on the Positive side of the battery. The meter should read near or at ZERO ohms. There should be a direct connection between the two with a fusible (low resistance fuse) link in-line. If that is OK then check for battery voltage on the field terminal of the alternator with the ignition key in the RUN position. The return path for both of these is the case of the alternator. If the return path is in question, attach a heavy gauge wire from the case of the alternator to the negative post of the battery and recheck the alternator heavy post/electrical terminal for something greater than +12volts with the engine running at say 2000 RPM or above idle if the two previous checks were OK. Suspect that one or both are NOT OK.

What is the item that you are cooling the "Head Unit"??? Please use the proper terminology such that appropriate advice can be issued. It sounds as though the Alternator is good but the wiring is faulty and not connecting the alternator to the battery properly. Do you have the wiring diagram for the 240Z? What is the "Digital Gauge"??? What does this gauge indicate? The 240Z has the ammeter in series with the alternator and the battery to measure charge/discharge current. What is the ammeter indicating throughout all these exercises? An appropriately charged battery should be slightly greater than +12 volts. When cranking the engine for starting the voltage should not go lower than 8 volts DC. If it goes lower there are bad cells in the battery. When the alternator is initially charging after engine start, the alternator voltage should be +14.x volts. As the battery attains a charge the alternator voltage should taper off somewhat from +14v yet still stay above +12v. The newer alternators need only a small amount of current from the battery to provide excitation for the alternator field to cause it to generate 12 - 14 vdc. There may be an excitation return (2 wire excitation) to ground or battery negative to complete the circuit. Normally the case of the alternator is the return or ground path for both excitation and heavy current to charge the battery. The other heavy post or connection on the alternator connects back to the battery through a heavy current (low or no resistance to current flow) fused wire. Older alternator charging systems had more (complicated) wiring than newer charging systems. Hope this helps. Will look at the 240Z wiring diagram to see which OLD alternator system wiring IS NOT NEEDED.

I had the same idea as you just a few minutes ago about disconnecting things. The battery read 13.30V this time with the jumper cables. Before that though, I had the multimeter propped up still reading the battery while I turned ACC on and started disconnecting things. I disconnect power and ground to the head unit and wideband gauge. When I went from having no power applied, to power applied, the voltage would drop by around .08V and stick there temporarily. I then proceeded to disconnect power and ground to the head unit and wideband individually. I noticed when I had power connected to wideband, and connected the ground, voltage would drop by around .10 rapidly, then when I took the ground off, it'd climb back up, connect ground, voltage back down and it sticks at a certain voltage. I did the same with the headunit and it didn't have nearly the same symptoms. So I immediately thought the wideband to be suspect. So I hooked up jumper cables again, started the car, took off the cables and monitored the voltage with the grounds taken off both the headunit and wideband at the same time, but with their power wires still connected, and the voltage was STILL dropping. I took off power to the headunit and same deal. I however didn't take the power wire off the wideband yet, but I figured that'd be a lost cause. So right now, I'm at a standstill and more confusion. I'll start tracing more wires when I have more free time. But as off now, I couldn't visibly see any exposed wires. What is the item that you are cooling the "Head Unit"??? Please use the proper terminology such that appropriate advice can be issued. It sounds as though the Alternator is good but the wiring is faulty and not connecting the alternator to the battery properly. Do you have the wiring diagram for the 240Z? What is the "Digital Gauge"??? What does this gauge indicate? The 240Z has the ammeter in series with the alternator and the battery to measure charge/discharge current. What is the ammeter indicating throughout all these exercises? An appropriately charged battery should be slightly greater than +12 volts. When cranking the engine for starting the voltage should not go lower than 8 volts DC. If it goes lower there are bad cells in the battery. When the alternator is initially charging after engine start, the alternator voltage should be +14.x volts. As the battery attains a charge the alternator voltage should taper off somewhat from +14v yet still stay above +12v. The newer alternators need only a small amount of current from the battery to provide excitation for the alternator field to cause it to generate 12 - 14 vdc. There may be an excitation return (2 wire excitation) to ground or battery negative to complete the circuit. Normally the case of the alternator is the return or ground path for both excitation and heavy current to charge the battery. The other heavy post or connection on the alternator connects back to the battery through a heavy current (low or no resistance to current flow) fused wire. Older alternator charging systems had more (complicated) wiring than newer charging systems. Hope this helps. Will look at the 240Z wiring diagram to see which OLD alternator system wiring IS NOT NEEDED. Source: Suddenly not keeping a charge.

Talk to MSD product support and they should be able to suggest the proper adapter.

Provided the tachometer has not been damaged, I think that MSD ignition has adapters that go between the HEI and Tach that clean up the signal from the HEI to the Tach.

The Speedhut Tach already has turn signal indicators within the tach. Thats more than Autometer does.

Let us know how the titanium wrap works out. Also order ARP stainless steel 3/4" header bolts with drilled holes for safety wire. Safety Wire has been used in Aviation for MANY years. If done properly the header bolts will not back out. Also use anti-seize on bolts going into the heads as it will be much easier if they have to be removed.