jmortensen

GREAT LSD info: http://www.gordon-glasgow.org/lsd1.asp If you want to buy a NEW LSD, http://www.reiderracing.com/home.htm has the R180 and R200 "Power Brute" for ~$500. The Power Brute is a rebadged Nissan LSD. Both the R180 and R200 sold by reider racing the much stronger 4 pinion units. If you want a Subaru diff, the mid 80's XT Turbo came with a 3.7 R160 with LSD. It was the same clutch type LSD, and the manufacturer that makes them for Subaru is the same one that makes them for Nissan, Fuji Heavy Industries (parent company for Subaru too, IIRC). There's also the Quaife gear type LSD that runs ~$1500 and is way overpriced IMO. I guess Australia has some gear driven units for under $1000 (not sure if that is AUD or USD) but that would be a better deal than Quaife, personally from what I've learned about them I prefer the clutch type. Info about shimming the LSD tighter for anyone interested: http://forums.hybridz.org/showthread.php?t=92629

And boobs!

Sounds like it has dual downdraft Weber DGVs to me. If that is the case the car would run better with two roundtop SUs, or better yet with triple sidedrafts.

This guy and my friend both had this problem when the shifter was in 1st gear. I don't think the spring in the shifter would affect this problem at all, since the reverse rail isn't even engaged by the shifter at all when it moves. I brought this up on another forum and coincidentally the guy who responded was the one who was driving my car so many years ago. He said that this later happened to his 5 speed Roadster trans (same shift rail setup as the Z trans) and he said the solution was to shim the spring over the detent ball, or replace the spring. You can shim it by putting small washers on top to preload it, or just get a new one from Nissan, apparently he said they are available and cheap. You could do just the 5th/rev rail, but might as well do them all...

This happened to my transmission on the track. My friend was driving my car, came around a corner and downshifted from 3rd to 2nd and got 2nd AND reverse at the same time. Needless to say that locked up the rear and the car slid off the track and past a brick corner workers' stand, misssing it by only 3' or so. Same thing happened to a friend's Z. She came over to my house, and pulled off in the dirt. When she made her U-turn to park on the right side of the street, she peeled out, when she hit the asphalt the trans locked into 1st and reverse I think it was. Anyway, she didn't notice because she coasted across the street with the clutch in, but when she went to leave at about 12:00 AM she was stuck. Same thing happened to her again about 6 months later. Trans was pulled, rods pushed back and that was that. When this happened to my car at the track my friend tried to put it into every gear, he wasn't able to really get all the way into any of them, but he kept monkeying with the stick and all of a sudden it fixed itself. When it happened to my friend's car the car we dropped the transmission and popped the covers off of the shift rail detent balls, then pushed them back in place from there. Weird problem, and I still don't know the cause. I think you need a certain amount of vibration and a certain amount of luck to do this. Maybe increased spring pressure on the detent balls might help (???).

The late E88 has a larger EXHAUST valve. There is no room on an L24 block for the larger intake valve. If you install the larger intake valve you'll have to notch the block for the intake valve to clear, and even if you do that, the valve will be so close to the cylinder wall that it is questionable whether or not that would be an improvement over the stock intake valve in an L24. If you were putting this head on an L28, then yeah, by all means put the larger intake and exhaust valves in. For the L24, you can make an argument for putting the larger exhaust in or just leaving it alone.

I would say that this is definitely a 240 body based on the towers.

That difference in the shock towers is another way to say what I was saying previously. I had never seen pics of the towers side by side like that. That seems like an easier way to tell than measuring the strut OD.

The 260 really is the bastard child. 1/2 of them had 240 bodies, 1/2 had 280 bodies. There are easy to recognize differences like the bumpers, but I don't know if that tells you which body you have in all casee. If you can search you might be able to find the different OD of the strut tubes (240 vs 280), then match that up and figure out which one you have. That would be a sure fire way to tell I think because the rear struts on the 280 body are longer so they can't be used with the 240 shell without modification.

I'm not sure what the problem is but be aware that properly adjusted drums SHOULD drag a little. If you can spin the axle with the drum on and it freewheels for 2 rotations you need to adjust the shoes out.

I ran the ITG for Mikunis on mine for ~40K miles. Eventually it did lose the crank pulley and I had to build a new shortblock because of that. There was no readily apparent engine damage from dirt (like a real bad ring ridge or something of that nature). The big advantage to the ITG's over the K&N's is that the air can go straight down the throat of the carb without having to go around the chrome plate at the end of the filter. I think you're seriously splittling hairs with SU's, though. When I ran SU's I cut the air horn out of the stock air cleaner housing and mounted them inside the K&N's. Worked fine for me.

Gasless mig = http://forums.hybridz.org/showthread.php?t=105610

Just do your best impression of this: http://www.modern-motorsports.com/catalog/product_info.php?manufacturers_id=&products_id=8

That is a very good tip. Wish I knew that when I originally installed my old Z-Quip early ZX setup. Totally unnecessary to have 4 bolts mounting it, and it requires you to pull the stub axles to bolt it up. It is easy to cut part of the bracket off and use the other 3 bolts and then the stubs can stay.

I just read a bunch of stuff online, started with the recommendations for amps and wirespeed on the welder itself, then I had a friend who has welded for years give me a few tips, probably the most helpful was to listen to the sound of the arc and adjust the wirespeed accordingly. If it sounds smooth then you've got it about right. If it is popping and sputtering then the wire speed is too fast. I'm not the be all end all welder though. I've thought about taking a class at the local community college, just never seem to get around to it.

I bought my Millermatic 135 from an ebay seller named "weldfabulous". They gave me a pretty good deal. It was the 135, a Hobart helmet and a pair of gloves for $607 including shipping. Then I had to get a tank which was $135 IIRC, cart was ~$50 or so. When I put my regulator on the bottle it IMMEDIATELY blew up. I could have sent it back to Miller, but in talking with some friends apparently the regulator that the Miller and Lincoln comes with sucks, so I just bought a nicer one which was ~$100. Other little odds and ends makes up the rest of the $900. The thing I like about the Miller 135 or the Lincoln 135+ or equivalent is the infinite heat AND wire speed controls. Some of the cheaper units don't have the infinite heat adjustment, instead they have 4 or 5 click settings. This can be worked around, but I wanted to really be able to fine tune it, and I thought it justified the price difference between say a Hobart 135 and the Miller (which truth be told have a lot of the same parts in them). I'm stitch welding the chassis on my car so I'm doing A LOT of sheet metal welding. I'm a relative newbie to welding, but I have to say I've made some SWEET looking welds with this Miller, and I attribute that to the welder much more than the operator.

Arc welding has its purpose, but I don't think working on a Z is it. Z metal, even the frame rails, is too thin for arc welding I think. If you were going to build a trailer or fix a fence arc would be a good choice. For fixing your car, especially if you are going to weld any of the paper thin Datsun sheet metal, a gas shielded mig would be a much better choice. Not wanting to rain on your parade, but that's the truth. At the very least I suggest you practice A LOT before you strike an arc on your car, so that you know what kind of results to expect. Try to use thin metal like you'll find on the Datsun too. I think you'll find that your arc welder is tough to use on thin stuff. I spent about $900 on my mig welder with cart, bottle, helmet gloves, extra spool of wire, pair of welding pliers and a big wire brush. That was the best $900 I've put towards my car. Enabled me to do all kinds of projects I couldn't before.

Thanks for the vote of confidence, although all I've done is autoxed for 10 years. That jetting looks pretty similar to mine, except the pilots and the pump nozzles are smaller. There is no doubt that Todd knows way more than I do about these carbs. One thing I can say is that road racing guys generally don't care at all about transitional response since they are always WOT at high rpms, so they might not take the time to tune it in as closely at low rpms. I've got 44s set up like this IIRC: 37mm chokes 50 pump nozzle 67.5 pilot 155 main 210 air OA blocks Also the fuel requirements are going to be pretty drastically different based on what cam you have. Your Z should definitely run well enough to figure the fine tuning out with those jets. I'd suggest you stick with the small pump nozzles for now, get an O2 sensor installed before you mess with anything so you can see the changes. If you were going to put money in jets first thing to try would be bigger pilots. I really like Todd's idea about "zeroing" out the linkage by loosening up the arms first, then synchronizing. Another tip on pilots I've picked up is that the pilot should be sized so that the car runs best with the pilot screw adjusted out 1.5 turns. If you need to back the screw out farther than that then you need a larger pilot.

Actually it is a rich condition, but it will show up on an O2 sensor as a lean condition, which makes it kinda confusing. When the throttle is closed and the rpms are low, there is a strong vacuum behind the throttle plates and the air that leaks past the plates is moving very fast. When you slap open all 6 44 mm butterflies the vacuum goes down to almost zero and the air in the intake slows down as well. Right at the same time you dump a bunch of fuel in. You'll find that this problem doesn't happen if you roll onto the throttle. Only when you punch it from a low rpm. At rpms above 2500 or 3000 the velocity is already high enough that the engine won't stumble. It is this combination of low vacuum and rich fuel condition that causes the stumble. The O2 sensor will read lean here because suddenly the air velocity drops. No O2 into the chamber, no O2 into the exhaust. You can see this effect on dyno sheets done with wideband O2s. Air/fuel will go from 14:1 to 10:1 until 2500 rpm or so, then jumps back into a reasonable range. What's interesting to me is that the car will pull better through this spot with the bigger pilot. I spent a lot of time on this in my Z, because I had a lot of situations where I would come out of a turn at a low rpm at autox and the thing would stumble. I was reading the O2 sensor and it was showing lean when the throttle was opened, so I kept going to a bigger and bigger pump jet nozzle thinking that would help. It did at first, but at a certain point it wouldn't make any difference how much larger I went. Then I read online that the O2 would show lean in this spot despite the fact that the car was actually super rich, and it also recommended using a larger pilot and not the acc pump nozzle to fix. So I tried that. MUCH better. I was surprised at how big the pilot had to be. I kept making it bigger and bigger thinking that it couldn't possibly run better with a bigger pilot, and it just kept running better and better. I think the pilot works better than the acc pump because the pilot only puts fuel in when there is air to burn it, where the accelerator pump will pump a big stream of fuel with no air to burn it. Mine still has a tiny bit of a hesistation there, but I just don't think it can completely be alleviated on the 44's. That's my understanding of the problem and its causes anyway. texasz--thank you for the .pdf. The info there combined with the info in the How to Hotrod Your Nissan/Datsun OHC Engine book should be enough to give anyone a good understanding of whats going on, but those Mikuni manuals are few and far between.

I used the exact same Behr epoxy that was first asked about in this thread. I bought my house from an old lady and the garage had been used but there was only a very small spot probably a foot in diameter where there was oil in the concrete. I followed the directions on the can as closely as possible, and cleaned the crap out of the floor before I put the epoxy down. I rolled it on with the garage door open, and still ended up getting VERY high off of the fumes. Whew. It was funny cause I had a friend there helping me and when we started we were making nice straight lines back and forth, and after a while our lines were... less than uniform you might say. It looked great right after we painted it. After a couple of years of using it I can say that the epoxy held on reasonably well under the abuse of rolling a floor jack, but it couldn't take scraping. I dropped the transmission out one day and slid it over so I could access the pressure plate bolts and it carved a big chunk out of the epoxy. Also jackstands could scratch through the epoxy as well. Some ATE Super Blue brake fluid definitely left a blue stain in the epoxy. Oil cleaned up easily though. So it stained, it was fairly easily scratched, and the foot diameter oil spot that I painted over did eventually start to peel back. It was easy to clean though, and spills wiped right up. The one thing I really liked about it was that the white floor would reflect light under the car so visibility was pretty good under there. I think it would have worked better if the floor was NEW when the epoxy was laid down. One last thing, I was working in a business at the time where the entire warehouse floor was epoxied. The only time that floor lost any of the epoxy was when a piece of the concrete chipped off. That was TOUGH stuff. I asked the owner of the building about it and he said it was "rated for food service", not sure what that meant, but he also said that it was TOXIC stuff and the guy who put it down used a full rebreather suit and still got very seriously ill from the fumes. That epoxy had been down for maybe 15 years by the time I came around. Epoxy can definitely work and be tough, but the keys are using the right stuff, applying it the right way, and putting it on new concrete IMO.

reegs, You get more pressure from a smaller master. More volume from a larger one.

Get an O2 sensor installed in the exhaust system. Just a simple one wire narrow band O2 sensor is what I use. Hook it up to a voltmeter or get an air/fuel gauge to read it. It will tell you where you are lean and where you are rich, which is very useful info. Then you need to learn some about Webers in order to tune the air/fuel ratio appropriately. They have a lot of different parameters you can mess with, much more than Mikunis (one of the reasons I run Mikunis). Here is a very good thread on Webers: http://forums.hybridz.org/showthread.php?t=93343 The fact that you have that much gas in the oil leads me to believe the rings might be bad. You might want to start with the oil and filter change then check the compression first. The fact that you have an unknown cam doesn't make the tuning process any harder. You still need to know when it's lean and when its rich and adjust accordingly. I've never heard of anyone who could tell you what jetting to use just by knowing the cam. You still need to adjust for that particular block/head/compression/intake/exhaust/etc combination so I don't think that your mystery cam is a handicap at all. BTW Norm would be WAY faster with triples.

That sounds really nice Sean. Perfect agressive street car exhaust. I wouldn't mind hearing it from outside the car too.

The diff actually sat about 1" forward in the earliest Zs (comparatively) and when it was found that this created vibrations and U joint failures they moved the diff back about an inch in mid 71 to compensate. The mustache bar is different, and the transverse link that goes behind the diff cover is different. I think Nissan had a recall on this and some of the early cars were fixed at the dealer. Quite a few still have the diff in the forward position. The rear sway bar looks similar to the current Suspension Techniques bar but they have stamped ends, not the welded ends your bars have. ST includes new uprights that the sway bar attaches to that look pretty much identical to what you've got there. Yours are evidently pretty old, might be Mulholland (?). No idea on the springs. Not sure why the holes in the bar are different sizes. Maybe they changed the stud size on the R180? Or maybe somebody installed an R200 and drilled out the holes (although I thought they were spaced wider on the R200).

Leave it alone and learn to love that noise. Richening it will make it lessen a bit, but it isn't a problem and your mixture should be set to make the car work when you're accelerating, not decelerating.