RebekahsZ

I got one PM-reply on my request for wiring help. I'll try being more specific. I have a '72 240z with LS2/T56 from a 2006 GTO. I had my wiring harness and PCM re-worked by waitformeperformance, but I can't get them to answer my questions. 1) Yellow "Accessory Voltage" wire: do I need it? Does it need a fuse? Where is the most convenient source (best if under hood) to tap into a wire that is hot with key in accessory position? 2) Blue/Red "Stop Lamp Switch" wire: If I am using the Datsun brake pedal with it's switch, do I need this Blue/Red wire from PCM? 3) Green/Blue "Park/Neutral Position Switch" wire from PCM: what do I hook that to? 4) Purple/white "Output to Speedometer" wire from PCM: do I connect that to the Cable-X? 5) VSS wiring from tail of transmission: Is this the proper source for the Cable-X? If so, which wire do I splice off to the Cable-X - the Blue/White, or the Bown/Orange? 6) Orange/Black "Battery Positive Voltage" wire from PCM: Confirm-Does that go to my new fuse block thru a constant-on circuit with a breaker, or straight off the positive battery post without a breaker? 7) Purple "Crank Voltage" wire: does that get spliced into the same wire that activates the starter solenoid? Does it need a breaker? 8) Yellow "Starter Relay Control": what do I connect that to, and what is a good, accessible location to find and splice into? Does it need a breaker? 9) Brown "Engine Control Relay Coil Control": what do I connect that to? 10) Backup lights: Confirm that I simply wire the Datsun backup light switches directly to the backup light switch on the passenger side of the tranny? 11) Confirm: I can cut and cap the light green "brake light" wire coming fromt the PCM? 12) Confirm: I can cut and cap any wires labeled for the clutch or brakes? I have attached pictures of my basic layout. There is one picture that shows the Painless 7-circuit fuse block on the firewall that has 4 switched circuits and 3 constant circuits. I have a remote battery in the trunk with long cables going to bulkhead connectors on the firewall. A third bulkhead connector will allow me to send switched power thru the firewall for my add-on accessories like a line lock and a 2-step rev limiter. The PCM mounts on the inner fender to the left of the fuse block. I will mount 2 fan relays to the right of the fuse block. I found an ignition switch "on" source at a wire coming off the Datsun wiring harness by the old voltage regulator plug: I connected that to the pink control wire that activates the Relay turning on the switched power circuits of the Painless fuse block. Any recommendations will help. I sure thought that after sending my harness off to a service, this would be a lot simpler. Maybe you guys can help me? Keith

The widest rim I have been able to mount without having to mod a bunch of stuff is 7-inches wide. Now, the tread width on 205/50/15-225/50/15 tire is about 9 inches. 225/50/15 on a 7-inch rim with 4.5" back spacing (measured from back lip of rim to hub mounting surface) is a perfect set up-you don't have to modify anything. At 8 inches, you have to start modifying things like rolling fender edge. At 4.75" back spacing, you have to go to coilovers to clear the spring seats. With coilovers, you can go to as much as 5-1/8 back spacing. Hope that helps. All these guys with super wide wheels are cutting out their fenders and adding flares. I have recently been thru this very issue, and I am certain of my measurements. Unfortunately, some wheel makers talk in terms of back spacing, while others refer to offset. Offset is really hard to measure. Best to get somebody who has the wheels you want do a back spacing measurement. Even then, try to just order one and set up the purchase so that they will accept returns.

Just saw your car with the CCWs, I like them, but I liked your old ones too. Wheels are like women: we like good ones, but we are never satisfied with the one we have. I have 4 sets of wheels and I still want different ones. Same wife 23 years.

Thanks for indicating that the conversion cost $5K. I've been thinking of skipping from an R180 to an R230, passing over the R200. But, it sure won't cost me any $5K. Cost seems to really pile up whenever I start a project. I'm gonna try to break an R200 before spending that much. On autocross, unless your club has lots of space to race in, most courses are too short to support a ton of speed. You likely won't get a chance to use all your power and will have to worry much more about stopping than going (I'm talking tires, not brakes). You'll be fine-I bet you don't break anything other than the bank. If you get too heavy footed, you'll just spin out. I've seen guys with lots of power beat themselves silly by over driving. Drive slow and you'll go faster. I'm putting an LS2 in my 240z for drag racing and general horsing around. I'll autocross it, but I don't really expect to be any faster, in spite of the added power. I applaud you for keeping the IRS-me too. It is a big part of what makes a Z a Z. Keith

I'll take some pictures tomorrow. I kind of crashed after I burned the wire and went to the movies with my family. The wire I burned is the black one with red stripe that grounds the black center plug on the LS2 PCM to the passenger side head. I'm hoping I didn't ruin the big PCM plug. It was my fault, I just got sloppy. I found an hour of energy after the movies and pulled the engine back out and stripped all the casing off the harness (have a little more to go) to assess damage. I will be sending the harness and PCM back to waitformeperfomance for diagnostics, repair and replacement of that wire. It is only money (and time), right? Between now and Monday, I am going to adjust the length of some of the wires, since I have the casings off anyway. I'll try to take really good pics so that my questions make sense. Thanks for volunteering to help me-I can repair a ruptured eyeball, but I don't do wires. By the way, since you are from NJ: tommorrow, I'm supposed to approve the final draft of my daughter's Princeton application essay. It is due prior to Jan 1. If she gets in that will put a damper on my z-car budget!

Just fried engine wiring harness. So much for getting car running before holidays are over. Pulling engine again to strip wiring harness and sending everything back to waitformeperformance. Looks like I at least fried the main power wire and connector that runs throughout the harness. Hopefully didn't burn up ECU. This harness has every wire labled, but it assumes that you have a basic understanding of wiring (no instructions came with harness when it came back) and has a ton of wires without any fuses, relays or connectors. This kit is not user friendly for the unskilled and is definitely not "plug and play." Did I mention that I am very discouraged? As usual, any advice is appreciated. Sending it back to try again in a few weeks. I was at least able to get motor to turn on the starter and got lights working, etc, before I burned it up.

I am in the garage today trying to finish the wiring. I've only had one fire today-we'll see how much of the harness/ECU I've fried-glad I installed that quick disconnect on the ground wire. I let my positive lead to the starter ground out to the engine block while I was searching for an accessory "on" wire under the hood. Didn't find the "acc on" wire cause I almost crapped my pants when smoke started coming out of my main connector to the ECu. The connector is lightly burned and may still function-we'll see. I have the battery cables wired from the trunk to the firewall with bulkhead connectors. I have my fuel and fan relays mounted and I understand how to wire them. Problem is the few wires that are marked from waitformeperformance (who is at a car show until next week), but I don't know what needs to be run thru the fuse block and what can be wired directly. I can turn over the motor with the ignition key. Also, what wires can be neglected (backup lights, etc). If you can help me, especially mnoel and cable, but anyone else please chime in-I want to finish this wiring this week and my wife is all over me to do stuff for her as soon as I can. Call to my cell 256-366-4685 if you can help me while I call out a few wires and ask advice on each one (probably less than 10 wires). Thanks, Keith

There is somebody selling a full set for $50 on the Parts for sale forum. Listing is something like "cleaning out garage." or "garage full of stuff". Looks like 280z lines.

Sorry guys. I found my reading glasses and the cable is square like it should be. It sucks being 40+! I did cut off about an 1/8" to match the length of the stock cable. Sorry about the false alarm. Gonna pull an all-nighter and try to get over the wiring hump.

The speedo end of the cable-X cable is round. The speedo end of the stock Datsun cable is square. Do I just take a file to the cable to make it square, or am I missing something? Keith

I just bent all new lines for my 72 240z and it was a suck job. I bought stock line in a spool from Advance Auto, bent it and flared it. It was a pain. Had to do several lines twice because of bad flares. Had to make several lines twice because of a pinched bend. Had to several lines twice because I made a good flare only to learn that I forgot to put the line nut on first. If you are trying to re-use the stock mounting looms to hold the lines to the chassis, and you have a source for pre-made lines that follow original specs: I would pay a thousand dollars to avoid doing that job again. My hands still hurt from that job. But, maybe you have a rotisserie-I did it on my back and it sucked. I am a surgeon so I'm decent with my hands, and I have a $500 a month car work budget-I'd buy them if they cost even $2000.

Will do. Thanks.

So, johnc, are you in favor of a little compliance, or against it? I'm just going to the track to have fun, I'm not trying to win a national championship-I got a non-automotive day job. I'm finding there are three basic categories of forum members: 1) tire-kicking, bench-racing, critics and hackjobs who need to wear a belt more often; 2) guys who are building sweet driving machines while balancing priorities of family and a steady job; and 3) the pros. I'm in category #2. I really appreciate the advice I've gotten on this thread-it seems to be all from categories #2 and #3, and none from category #1 for a change. Thanks, guys.

Great. Thanks Leon, that is reassuring-I have ordered a spindle pin puller, but I don't want to use it very often. JMortensen, I'm not worried about the fact that the outer bushings are rubber instead of poly. Honestly, there is not that much rubber in the outer bushings to start with if you figure there is the metal casing and a metal tube that the spindle pin goes thru. That leaves very little room for either rubber or poly-I can't imagine there is much deflection either way. Thread for a used set posted. LSD I was chasing sold to someone else. If nobody bites on used add, I'll order a new set at week's end. Decision made, thanks everybody, I'll post my results. Ordering a camber gauge too, so I can speak intelligently and compare apples to apples. I have a toe gauge, but I will only use it for mock-ups and will still have an alignment shop double check my track measurements and my final toe using bearing plates, etc.

As the title says. Checking the forum to save a little money. Please PM me if you have some you want to sell. Must be complete.

Thank you all so very much for your advice. I'm going to follow this thread hoping someone can put a tape measure to their LCAs. Johnc, 14.5" is what I got on my stock LCAs, too. JMortensen, I hope you are right about the arm NOT being threaded, because if it is, the spindle will have to come out to adjust. Brandon, I already have camber plates-I'm working around a bunch of conflicting issues to get my tires to clear my unrolled fenders. I would roll my fenders, but they have been cut and spliced together and I don't think they would roll correctly. I wish I had a ratsun so I wouldn't worry so much about my paint job, but I have really nice paint and I truly regret not fixing my fenders before having it painted. If I didn't have stock fenders, I wouldn't have this issue at all. Over the years, my goals for this car have changed. First it was to look good, then it was to handle as an L24 autocross car; now it is to drag and autocross with an LS2. Compromise is the enemy of excellence, but I have to make a lot of compromises. I'm going to order a set of the MM LCAs and I'll give a report back in a couple of months. If anybody has a used set, I'm in the market; I'll put a parts wanted thread in and see if anybody bites before ordering new. The LCAs and an R200 LSD are competing for the same pot of money.

Thanks guys, but this is a multisport car: show, cruise, road trip, daily driver, drag, autocross, and maybe a little drifting. I toy with all of it, but am not super serious with any of it. As a result, the car will probably not stand out and shine in any particular category, but I'm ok with that. So, no solid or backhalf for me. I am serious about reliability and quality construction. No junk build here. Mods, please kill this thread if you can; I've started a new one.

I am strongly considering buying a set of Modern Motorsports Adjustable LCAs. Ross replied to my email inquiry promptly (in less than one day); he has several sets in stock in the warehouse to be shipped, but he can't get to them to measure them for me because the warehouse is far away from from his office, maybe even a different country(?). Anyway, what I need from somebody who has already bought these, is an estimate of the range of adjustment. 2 specific questions: 1) what do you estimate the minimum and maximum possible lengths of these control arms, measuring center of outboard bushing to center of inboard bushing. I have attached a photo of my stock measurements. 2) how do you adjust these? Do you have to remove the spindle pin every time you want to adjust the length on these? How easy is it to adjust them once they are on the car? This is a follow-up thread to one I started last week. The up-close photos exaggerate the angle of camber and the distant photo under-represents the amount of camber a bit. I included these to show that I'm not totally slamming the car like a low-rider-my LCAs are not even flat. My Wolf Creek axles have 3/4" to 1" remaining end-slack-it was easy to estimate-I just grabbed them and pulled back and forth; I don't think I'll have any problem bottoming them out if I shorten the LCA a bit. If I can pull the bottom of the tire in a bit, I may be able to kick the top back out a notch. I have looked at the TechnoToys LCAs and the old tubular Arizona Z LCAs (which are no longer in production-maybe?), and I don't think they have the range available to be shortened. I have a lead on a nice set of stock LCAs that I could shorten, but I'm afraid I'll over/under do it. Thanks-Keith

I haven't gotten a PM back from you, but I see you have been active on the forum a lot. I see on your updated list that the 3.9LSD and the control arms are SOLD. Are they sold to me (hope in my voice)?? Maybe something is wrong with the PM system? Could you call me at 256-366-4685 or email me at pkeiththompson@yahoo.com and let me know if I'm the winner or not? If I am, I'll pack up the truck and come get them. If not, I'll move on downtrodden, dejected and broken hearted....

PM'd on Arizona Z rear control arms. Eager to buy them, send me a paypal address. Keith

Mark and TimZ- Can you each describe in more detail what you did with the various brand control arms you have used. The sites say the control arms can't be shortened, so before I spend money, I'd like to really have my act together. Got any pictures that show what changes you did to the LCAs to make them shorter. I'll contact Cobra Matt and check into his parts. I'll also surf the brands you recommended and watch for your replies. I have ordered a spindle pin puller, so I'm serious about doing this mod.

PM 1tuffz. He has installed and raced this kit and advocates for it.

Thanks for all the recommendations, sounds like I'm in unchartered waters. Mr. Mortensen, I'm planning to use your axle shafts no matter what-saving Christmas money right now-just got a little more! I'll start with your current design and see if that will work before trying something special there. If the shafts are too long, I'll let you know and we'll go from there. One of the problems is that I've got to study my geometry to know how much to shorten the LCAs. I'll add a photo of my camber to this thread and maybe somebody can advise me on how much I should cut out of the LCAs. I already have coilovers and camber plates, and the correct offset rim-I'm maxed out on all the traditional stuff. I am equally crowded between the tire and the fender, and the tire and the strut. I have checked with Arizona Z, T3, etc, all of their LCAs are built with INCREASING length in mind and they are not set up to be shortened less than stock. I'm gonna have to either cut something or get skinnier wheels/tires. I'm running 26X8.5X15 (which has a 10" section width) slick on a 7-inch wheel with 4.5" BS. Think of the tires as being 10" wide. I'm gonna wait two or three more days for more advice, then I'm gonna buy some LCAs and start working on it. Last guy I'm hoping will weigh in is JohnC.

Nice car...I am so sorry. Anything is repairable, but not everything is worth repairing. No right answer. I'd look for a replacement chassis, park 'em next to each other and swap parts over. Again, I am so sorry-I've been the victim of a hit-and-run..it just feels terrible.

I am working to reduce the rear track of my 240z to allow some wide wheels/tires to fit inside stock rear fenders. I have the tires clearing the rear fenders with the use of camber plates. But, I now want to reduce the induced negative camber. I don't want to raise the ride height, and I don't want to cut/flare my fenders. I have some offset bushings, but they don't reduce the track enough. Do any of the after-market control arms allow for REDUCED track/de-cambering? Has anybody out there cut and welded their stock lower control arms in order to shorten them? Anybody got a set of spare, straight LCAs that they would sell me to experiment with? Next question will be: how much length to remove? I'm kind of thinking an inch or more... Input??? Send pictures if you got em'. Keith