seattlejester

Hi guys, I was hoping to get a couple second opinions on a noise I am trying to track down. 240z 7mgte R154 Custom driveshaft R200 I've just recently checked the rear suspension bolts and added lock tite to the cross member bolts. It's an intermittent rattling noise. I can best get it to occur consistently when the car is warmed up and I rev the engine and let it rev down. It occurs about 1000-1500 rpm from best guess. This happens when parked or driving. I've checked to see movement from the driver seat through the transmission tunnel, the driveshaft and exhaust don't seem to be moving so I think it is safe to isolate the noise to the front end. It could be something as simple as a loose fuel line, but I just wanted to see if anyone can offer alternative ideas as to a noise of that nature. I think I've convinced myself it most likely is not drive train related, but thoughts would be appreciated. I'd best like to tackle the problem head on with multiple possibilities.

I used a pair of electric shears to liberate mine. I just trimmed in a circle. If it has a flange you could cut yours a little smaller and then place the wheel well on top. Nothing really mounts to it so it would be ok if it was a few mm above where it sat. Ideally you would want a hexagon for easy instillation.

If you have help to pull the transmission up after it clears the engine bay it's not too bad on the out. A leveler definitely helps for putting it back in or if you are doing it by yourself. Don't forget the fuel lines and such. Good luck sir keep us posted.

Oh, that overlap. Hmm I don't have nearly as much on mine anymore, but my floor is fully welded instead of spot welded. Can't offer any structural advice there, but if you are going thicker it should be ok. I would poke and prod all the sheet metal in the surrounding area, that frame rail section seems pretty far gone, and it would be easier to replace any adjacent material while you have it up on the rotisserie.

I mean if you have the means to use it, then go for it, just know that know everything else is weaker then the new repair you made lol. If you have a plasma it should be easier as long as the cuts are clean or else lots of finishing work for the pieces. My brake was a cheap one and boy would it struggle bending 16. It would fold 20 gauge completely in half though. I built the frame rail first and welded my floor and firewall around it. I don't recall the overlap very well on the stock car since my floor was so far gone. I just didn't want to make the bend so I welded the firewall portion then the floor and let them meet up and then welded those and welded a piece to round it out so it wasn't at an abrupt angle. Could you take a picture of the area in question to refresh my memory?

Did you try both at the same time? Crack both left and right rear line with a small diameter hose sitting in a reservoir of fluid. Basically the pump forces the air out of the line and bubbles into the fluid and letting off draws fluid back up the line, repeat this a few times. I actually took video of the passenger side while I leaned out and watched the driver side, and to my surprise my "bled" lines pushed a lot of air on the passenger side when both were open. Feel free to give me a shout if you can't get it, it could be something simple that's being overlooked like brake travel.

You need to slow down, this is a different kind of forum, assumptions don't help you or us. Sit down, take a breath. You obviously felt you needed help by coming here and posting. Let us help. We need facts, unfiltered and clearly laid out. If you assume that the car is running fine before it dies, that is a problem in and of itself. We need to know how fine it is running. That means temperature, oil pressure, voltage, time it runs before shutting down, attributes when it shuts down, how long do you wait before you can drive it, what is the temperature outside. Hard numbers and facts. Best way to convey this information is in a list. Car dies when... It is ____ degrees outside It has been running for _____ minutes After cooling for ____ minutes I can start it again It takes _____ seconds of cranking before it starts The battery voltage is ____ volts at resting The battery voltage is ____ volts while running The coil is _____ degrees when it dies The coil is _____ degrees when I can start it again Everything you state should have a number/observation and unit associated with it. We can help or at least steer you in the right direction if you give us facts. Assuming that your electrical is fine (see how bad assumptions are? I can just gloss over everything with that), the "works for a while" problem comes down to a couple of possible problems. Fuel starvation, spark starvation. If it is running for a while that means the air and compression are ok for now. Fuel starvation breaks down into... Fuel supply insufficient, you said you have a regulator, does it have a gauge? Vapor lock is a thing on these cars especially in hot weather, it may be time to look for a fuel line cooler fan from a 280zx. Spark starvation... Insufficient spark won't light the mixture. Check the spark plugs, in fact take them all out and post them in a row and take a picture that in itself will tell a story. Check the coil when the car dies, is it hot to the touch? What's the car's voltage running and not running. You have a choice to make right now as well. Do you want to learn or do you just want a running car. If you just want to have a running car (there is no problem with that at all) take it to a shop. Have them sort out the electrics and slap on a warranty and drive around and enjoy it. If you want to learn yourself you have to invest, that means time, money, effort. You can't just have that kind of wiring mess sitting around. Get some decent tools and fix it. I see in-line un-covered fuse holder, open contacts, exposed fusible links.

It is strange that a metal shop doesn't have 20 gauge, but we should move beyond that. If you are willing to work with 16 gauge then so be it. Just for reference 20 gauge is just much easier to work with, 18 gauge is not bad either, once you get to 16 gauge, you can't use a lot of the cheaper benders, hole punchers, automated shears, etc that make your life really easy. I used 18 and 20 gauge, I didn't have the dies to reinforce the fire wall so that got thicker steel, and the floor I overlapped so I think the 20 gauge is fine. It is mistaken to think that just replacing a small piece of one portion of the car with thicker steel will strengthen the rigidity of the vehicle. You could do the floor and firewall in one piece, but that would be a fairly large piece. I did mine out of 3 pieces. One for the firewall, one for the floor, and then another to round the joining area. Given that you are using thicker steel it may not be as problematic to use one piece, the concern is how you will make the bend from the firewall to the floor without stressing the metal too much.

Oooh you are cruising, keep up the momentum!

I wouldn't say way more hp, but there are indeed a few R160 LSD guys floating around. I would build up honestly, especially if your end game is turbo. It's pretty easy to bump power in a turbo car if you build the peripherals to handle the power. You would be surprised how tempting it is to crank up the boost, or how affordable it is to buy a bigger turbo and injectors and turn that 200hp number into 250hp, then 300hp, and on and on. I would say get an R200 with an LSD, cv axles, and 27 spline stub axles and not have to worry about the rear end for a while. To answer your question though, yes you could get away with an R180 and skinny tires. The skinny tires will act like reliefs and protect you to a certain extent. I will warn you though, the bolts get real loose real fast with a welded diff, some lock tite and new hardware is probably in order.

You leaned out, as they have said above. The question is if this was a lean spike you hit or if you were just running lean the whole time and it was just a matter of time. Did you have the lean protection on in megasquirt? Did you have fuel cut set for the boost controller with a maximum kpa threshold? Adequate fuel pressure? Adequate fuel? Did you adjust your map after you bumped up the boost? How was your AFR? Do you have your data log of the incident? Do you have your current tune? If you just move to a metal head gasket and studs, you will end up blowing the motor again, but now you've removed the relief valve of the head gasket, probably with a cracked block or head, or piston damage. It is extra insurance, but you need to make sure the problem is gone before you go implementing that insurance.

Dying after running is usually limited to one of two problems (really generalizing here). Fuel starvation Electrical current starvation Throw a gauge on the return side using a t fitting to monitor the fuel pressure. If it drops to 0 then you know that your fuel pump is not supplying enough fuel due to a clogged filter, a clogged fuel line, an intermittent short etc etc. Throw a multimeter on the battery and watch it and see if it gradually drops, a low current will fail to get full spark. Or after it dies see how hot the coil is. An overheating coil will also fail to keep a car going. Check the alternator and battery and search out other drains.

From my understanding, it isn't that it is needed per say, but it is needed to keep the operating voltage in the right range. People were saying a 1/2-1 volt drop without running the charge light. Strange, I did the internal regulator and ran my car off of a stereo battery with the old motor. With the wiring done the way I posted it charges almost too well almost up to 15 volts (I have a 160amp alternator which may be the reason). Better track down that drain, having the ECU lose charge while the motor is running is not good.

There's 3 wires on the datsun harness IIRC you just have to run it to the same wires on the new alternator. I want to say most newer alternators are internally regulated so having the external voltage regulator delete is the way to go. It's been a while since I have looked, but there should be 4 wires I think, 3 wires from the alternator, 1 thick wire to the starter then to the battery. For the toyota Ig/ign - Ignition - ignition based power signal S - sensing - positive 12 volts straight from battery L - lamp, this is the resisted wire that provides the field I believe. I want to say these letters are stamped on the alternator to show which spade does what, all you have to do is match it up to the datsun wiring harness. On the datsun S - sensing - is yellow or the upper portion of the T-plug L - lamp - is the lower portion of the T-plug black/white Battery is the screw terminal pretty obvious Ig is not present on the datsun I think it just has an earth/ground, I took the ignition signal from the stock coil and routed it to the alternator, just find the ignition wire that triggers the coil and you can trace it back to the closest point to the alternator and steal the signal from there. In my case I just used the wire that usually connects to the coil split that and ran that to the alternator and the other one back into the cabin to trigger my relay box.

Guys, this is pretty old.

Oh wow, not even through an automatic, that's quite a bit of power to manage. That is unfortunate regarding the stock stub axles, did they survive a couple passes at least? Glad to see it was quickly remedied though. Hmm I wonder if the inner stubs would go or if the diff starts asking for trouble. I imagine you have a new drive shaft to accommodate the swap? Well glad you found the studs you were looking for.

You hit the nail on the head, it is in reference to the self adjusting. I know hotrod has tested and left generally good marks, but they too had to call in for reinforcements and help to help certain situations. You will have to learn it at some point, or hire/employ/enslave/befriend someone who does know it. It is not just about the fact you should know what is in your car and be familiar with it in case of problems, but it is in that you should know the theory behind it to make the decision on how safe or how risky you want to push it. Tuner studio offers an auto tuning option on their software for the megasquirt as well, but you still need to play around with other settings like cold start, idle, etc etc. Even with the analyze live running it didn't catch certain problems I had and left some quirks here and there. It runs a very simple algorithm, up to the user to take advantage of that. The point of it is that if you are purchasing it to cut the need for a tuner out of the situation, that's probably not a good idea. The point behind it is that it is a stepping stool to make you into a basic tuner. You run the tuning program, tweak here and there, call support and ask questions, get suggestions implement, and in that front you end up learning. Believe their pitch that you bolt it on and you never have to touch it again maybe a bit on the naive side, granted it seems like they are trying to make it easier.

Hmm kind of interested in your rear end setup. 1000hp is a lot, if you run big sticky tires, then you run into half shaft problems, you run big half shafts you run into stub axle problems, you run big stub axles, you run into diff problems, you run a bigger diff, you run into drive shaft problems? I'm curious where you've shifted your weak point. I mean at those levels of power it would be quite proactive to look at wheel studs, although I think it takes more effort to snap a well torqued stud then it would to break the tires loose, I mean I've seen wheel centers break before stock studs, but I imagine you go wide and sticky enough and throw enough power at it that would also fail.

I mean I'm not here to dissuade you, but to address your points... Regardless of the system you buy, you will have to either learn to tune it or find a tuner. You can shave the intake manifold, not anything new For the money you are looking at, you could even get a custom intake manifold. Your last point is completely valid, because it's different and a conversation starter/preference that alone is good enough justification. Good luck sir, keep us informed with how it turns out, been curious about the setup. Personally I think the triple webber carbs is a really good look.

That's a 215. I'll try and grab a couple this week. 225 looks almost perfect, no bulge, the 215 I had actually had quite a bit of stretch.

15x7 +0 225/50/15. Terrible picture Rubs on the rolled lip on big dips fully loaded, running 1-2 degrees of camber The magic inner number is 8.25 + 4 has a quarter of clearance to the inside if memory serves so you are fine on the inside with the 8 -12. On the outside you might be hanging outside the body a bit, but with the stretch and lower profile you could get by.

I would say you need a new fuel pump, a bypass regulator is going to cost more then a low pressure fuel pump. I'm a bit out of it so I can't recall on the EFI cars if the ECM controls the relay. I don't think it does. You just need to make sure the relay is powered by the ignition, if you are unsure just trace the wire from the distributor and splice in and steal the signal from there. That way as long as you have spark you have fuel. Supply 12 volts to the pump and it will turn on as long as it's grounded. Make sure to run a switch though as if you are tapping it against a 12 volt source that will generate sparks, and sparks + gas equals a bad time. Vent line to return the fuel tank? I don't recall any vent line for the carbs, just the vent back into the intake.

Seems a bit convoluted to buy a carb manifold, then replace the carb with a TBI system. Why not just run an EFI intake manifold? Would save you quite a bit. If you want room to grow you can get megasquirt or another aftermarket ECU. I mean at 2300 for the TBI setup, and 400 I think for the manifold. That just seems like a lot of money.

You can put your car on a track in stock form. Lowering it 3 inches alone will introduce quite a few more problems if you are just cutting the stock springs. Some camber will be introduced, less shock travel, bottoming out on the shocks, LCA angles being out of the ideal arc, having to reseat the springs each time you jack up the car, etc etc. If you plan on tracking it a better set of shoes and pads with high boiling point brake fluid and a good tune up will go a lot further then cut springs will. A lower sidewall tire and a corresponding larger rim will also stiffen up some feedback from the road. With that said, to answer your question, cutting a quarter coil and letting it settle each time would be the way to go. This is fairly tedious if you do it the correct way (disassembly followed by reassembly), and quite dangerous for the first few if you do it the easy way (cutting on car with suspension in full droop hoping for the best). If possible it is better to cut from the top as it will make it easier to seat the springs. If you are concerned about your stock car, then just keep it stock. Enjoy the short comings and enjoy the experience. If you are focused on track times then it may be time to kiss stock good bye or buy a beater car and make that your track toy.

First off, I'm going to have to berate you a little bit, so put on your thick skin jacket. We have forum rules regarding proper capitalization, while it may seem tedious it is more professional and helps to read through posts. So please try your best to hit that shift key. I suggest against the use of so many ellipsis, it seems like you are trailing off a lot. I understand you want to accent that these are thoughts in progress, but if you don't put your thoughts in words it is hard to help out. If you don't put what you mean to say...yea...you know...stuff...right...difficult...yea... Onto your questions.