zuperair

260 Carbs are flat tops. Round tops are 240 carbs.

Interesting.....hadn't thought of that scenario. Radiator was without fluid for about 3 months. That could be the answer. Guessing if I had it boiled, it'd be fine. Worth keeping on the shelf at any rate. Thanks!

Well, I've got it figured out. Sort of.... I found an upper radiator hose today that would work with my aluminum radiator....tossed in some new fluid and went for a test drive. Seems my stock radiator was the culprit, since I had no issues whatsoever. Could see the tick in the needle on the temp gauge when the thermostat would open...ran it hard, ran it soft, let it idle in the driveway for about 15 minutes. Dead center on the gauge! I took numorous readings with the Raytemp gun.... Head on the pass. side 155 all the way across. On the intake exhaust side 160 near the intakes, 195 near exhaust ports. The block was 155 (wooohoooo), and the radiator 145. Couldn't be happier. Now I can move down my list to the next thing. Getting very close to done now. Odd thing about the stock radiator...never had a problem with it. Always ran cool. I wonder if there was something in the head from the build that plugged up the radiator somehow. It's about the only thing that makes sense at this point. Anyway, thanks for the replies....I'll be posting up pics of the project very soon.

I thought I posted the radiator temp...guess I forgot that little tidbit. I did shoot it, and it was between 185-200 depending where I shot it. I did put in a new thermostat...I meantioned that, but didn't list that under new parts which I should have. Also, while searching...I ran into your thread from '03 "z car getting hot". Read through that, but unfortunately we have different issues (obviously your's is sorted by now) since mine gets hot while moving. Curious...was it the wrap in your case that was causing the overheating issue? I jet hotted my header....and figure there's no way it could cause this issue. But 'till it's solved I hate to rule anything out. Anyway....I'm sorting out the upper radiator hose for my aluminum radiator. I installed it and once I get the hose I can test it out...although, I'm not holding out much hope at this point. Everything I've come up with through research tells me the e31 works fine on an L28....anyone feel differently?

I've got a '77 280 with the stock L28 block and fuely head that I converted to an e31 head for use with triple dcoe webers. Before the conversion, the temp gauge was always about an 8th inch left of center. Pretty standard with many of the other z's that I've owned. After the head swap, the temp settles in for a moment at dead center...but after about 2 or 3 miles starts it's slow climb. It's highest point has been about an 8th of an inch left of 250. Not sure if it's stable there, since I shut it down as soon as possible (till now I've only test drove it no more than 10 miles). I used a raytemp gun on the head, and it showed around 185-190 near the intake ports, and about 205 near the exhaust ports. Intake temp avg about 160...header temp at head about 300. Block's temp is about 205. So far, I've re-timed it....put in a new thermostat (180), checked fluid of course, and I've ordered a new sender. Thing is, the Raytemp numbers aren't where the gauge is....but then again, this gauge worked perfeclty before, I'm using the same sensor, but it's definitely getting hot. Any suggestions would be greatly appreciated. Here's what I've got... Stock Parts 77 L28 Block Stock coil and Ballast resistor New parts e31 Head with Schneider cam, full valve job, top end is new Triple 40mm DCOE Webers (new) Hooker Super Competition Jet Hotted 6 to 2 Header Mallory mechanical advance distributor Aluminized 2 1/4" dual exhaust with Glass Packs and Ansa tips I've got an aluminum radiator for the car (new) and I was planning on putting that in after paint...but I may put that in just to test. Deal is... the stock radiator is like new, and it never had an issue.

I feel the same way about leaving something jumpered. I did set it up with a relay yesterday using the power source from the plug, the keyed "on" power from the ignition switch, and a local ground. I even went as far as using the stock fusible link that was in the FI loop. Yeah, I did remove all traces of the FI system. No harnesses, computer, relay or resistors. When I pull the engine and trans for paint prep, I'll even grind off the mount for the air flow meter and the mount for the air cleaner. Going to get it as simple looking as possible. Interesting! I ran the 32/36 dgv dual weber setup for about 15 years in my 260. Always off of the mechanical with no issues ever. Had talked with several guys that had pressure reg's on their fuel lines for that setup, but mine was a dream. This triple setup I bought came with the carter, so I just went with it. They said it wouldn't need a reg', and at least in the driveway they're right. We'll see once it hits the road and gets under a load

I do have the e31, but I can't run the stock mechanical since it wont have the right fuel pressure for the triple webers. They're kind of touchy on the fuel pressure. Interesting! I know the plugs intimately at this point. I have found the stock wire that leads to the pump, and have jumped that for a test. It worked, but I didn't think of jumping it from one of the other plugs that connected to the FI relay. I'll look at that today. I did buy a generic relay for the system yesterday. But, If I've got switched power in that FI harness somewhere, that would be an easy job. Mount the relay in place of the FI relay, and the wiring would be like a 9" harness tops. Oh, and the pump I'm using is a Carter matched for this Weber system. It works great. A little loud in the "Whirrrrrrrr" dept. but then again, I've got the car completely stripped down, no interior, carpeting, tail light assemblies. So, I'd guess with the car bare, it's louder than it will be when the car is re-assembled. I just got the exhaust system in it on Thursday. 6 into 2 Hooker Super Comp header (ceramic coated) into twin 2 1/4" pipes to twin glasspacks, piped to twin Ansa Turbo Tips. Just in the pre-tune stages now, but this thing howls!!!! I'll bleed out the new wilwood system this week so I can tune it for the road instead of the driveway. Up till now, I've just been using the custom emergency brake kit to stop the car here around the house. Thanks for the replies!!!

Thanks for the reply. After going over the wiring diagram I'm now thinking that there is no pump relay. I mistook the "fuel injection relay" for the pump relay the first time through it. It appears the the power from the pump comes from the fuel injection computer which is powered by one of the fusible links. Now guessing that the FI computer also acts as a relay for the fuel pump. I'll find the correct wire from that remaining harness, and put a relay on it. Should have it sorted out today if I can make the time. On the fuel pressure issue, you are correct on the lower pressure required for the carbs. I already swapped out the stocker for a carter. 3-4 psi is all that's required for the DCOE webers. Volume is what they really like...Hi volume, and low pressure. Sounds like a great sales job when I think of it that way

I haven't had any luck searching this topic, any help would be appreciated. I swapped my fuely head on my L28 ('77) for an e31 head and set it up with triple webers. I removed all the associated fuely harnesses and the computer as well the dropping resisters. Before doing so, I tested the connections at the stock fuel pump, and found that power to the pump is initiated only after turning the key to "start". The relay then must keep the pump powered after the engine is running I'm guessing. When I attempted to start the engine after the swap, I found that I no longer had any power to the pump, and have traced that to the removal of the fuely computer. I bypassed the stock wiring with a makeshift harness to the battery, and got the engine running (wicked cool) so I know everything will work. How do I wire my relay/pump so that I can use the stock wiring? Is there an easy way to power the relay off the ignition circuit? Thanks in advance for any help/suggestions!

I'd say junk yard for sure, if you can find one. Is the 240 collector the same as the 280??? If so, I've got one I'd just give you for shipping costs.

It'll probably help me out, so thanks. I've got an AZ Car Radiator for my project car, haven't given it much thought really since I'm not ready to put it in just yet. When I do, I'll try those hoses. What I've done in the past isn't that hard either though....Measure outlets, coat hanger, bend to proper angles and cut to length....small trip to Fleet Farm and about 20 minutes of effort to find a match (trimming always necessary). Thanks for the info though, it'll save me some time for sure!!!

No doubt the 210's plow, woooohoooooooo It's a '99 with a big bad 502 with 510ft/lbs of torque. Makes moving the weighted pig up and out on plane really easy! I rode in just standard gear through september this year....but most years I'd say about mid sept. I'd start wearing a shorty with a neo shirt, two/three weeks of that then I'd just put on my drysuit. Not the full baggy tho, I've got an O'niel that is 3mm neo on the bottom and then the full loose baggy top. That thing's awesome.

That's hysterical !!! Small world for sure...I've been riding with Justin plenty. Lots on the street and lots on the Ice. Still bummed about his bike being stolen. Us Italian bike owners stick together...and us Loretto-ites. Hopefully he'll get a new bike to ride for next year. Right now I'm hoping he gets an Ice Bike setup. We'll be riding soon! Thanks for the note Devon, who would have 'thunk' it... z

Good eye!!! Yeah it is....I've got a SuperAir Nautique with a 502 in it. Bought it new as a matter of fact. The wake is SICK! I've also got a Ski Nautique closed bow...live on a lake, livin' the dream. I used to be pretty closely tied to the industry, but these days it's all about the fun. Maybe next summer we should rip the Z's around a bit, and do some ridin'....I just pulled my boat off the lift last week. Finally had to call it. Now the lake needs to freeze so we can take out the Ice Bikes. If it's liquid I like it best, but frozen....we still tear it up!

Ok, so I was able to bring the car home last night. We worked on it both Saturday and Sunday to get the car finished with this step. Once I got to Al's on Saturday morning, first thing we did was assemble the front end. Al had already cut the strut tubes and welded the new adjustable ride height coilover collars to the strut tubes and spindle housing. From there, it was a matter of merely assembling the front. AZ Zcar instructs the front collars be welded flush with the strut tube base, and the rear they say to cut at 7 1/2 inches above the tube base. After the front is assembled they recommend assembling the rear loosley, then setting the car down on the suspension to see how much more may need to be trimmed to accomplish a level car, while leaving maximum height adjustability. So, I figured I would set up each corner with identical thread depth into the collar, and identical spring preload. So, I set the spring preload to 5/8", and since the adjustability range is 4" (their collar is actually 5 inches long), I screwed the coilovers into the collars 2 1/2". I figured this would give me the best look at where I am given this system, and given that from this point I would have 2" of up adjustment as well as 2" down. So, now moving to the rear. The rear camber plates were first up. The rear towers are assembled from the factory in such a way that there are several different layers of metal. Cutting them with the air saw wasn't an option here...so the small cutoff wheel had to be used. Doing it this way leaves a lot more finish grinding on the work list...but there doesn't seem to be anyway around it. Cutout before the finish grind.... Welding in the rear plate.... After the Camber Plates were welded in, we moved on to the Strut Towers, and modifying them to accept the new coil over collar. Firstly let me say that removing the pinions in the rear A arms so we could remove them entirely was an absolute @#$%*. Supposedly (by the service manual) you just remove the locknuts, remove the set bolt, and then just pull it out. LOLOLOLOLOL ROFL .... Now, my car has been amazingly clean and easy to work with throughout this project. Original owner, Arizona, yada yada yada.... tell it to the pinions. So, figuring that we'll be using full billet A arms and new pinions, our solution was a ton of heat, and a real big hammer and an air hammer. Once we destroying the bushings and the pinions, and oh yeah, removing them...we cut them off at the suggested 7 1/2" up the tower tube....here they are with the collars resting on them (not welded). From here, we just loosely mount them back into the A arm, screw in the coil overs into the collars 2 1/2" so they'd be identical to the front. Al then tacked them so we could loosely bolt up the wheels and set it down to check level of the car. So we set it down, and oddly...it was like almost 2 inches too high in the rear. I had measured the height of the car from the ground on all four corners using the rocker lip as a guide. Front measured out at 7 1/2" off of the floor....rear was 9 1/4". So, we pulled it apart after grinding off the tack welds, and cut another 1 3/4" off of the rear tubes...re-assembled them both...tacked them in again, loosely assembled the rear to bolt up the wheels, and dropped it back down. Badda Bing!!!! Level. After settling, the measurement was 7 1/8" front back, left right. AWESOME. At this point we dis-assembled the rear again so Al could do the final weld on the rear collars. After the final welds were in place, it was time for final assembly. I didn't bother assembling the brakes in the rear since I'll be doing the Wilwood brake mod this week....so this saved me about 20 minutes or so. Also, it made for a bit of fun driving it into the trailer with no brakes. We had it figured out pretty well, but it was a little funny doing it that way. Thanks for all the help AL!!!!!!! Anyway, that ends the AZ Car Coilover and Camber Plate install assembly. Holy #$+% is it stiff!!!!! Have to play a bit with preload and settings on the shocks...but man is it cool!!!!! Stay tuned....since my metal guy is off hunting this week...I've moved up the AZ Zcar Billet Chassis mods, along with the Wilwood brake mod, and the Skyline 3.90 LSD diff. Going to be a fun week!!!! Any input would be appreciated! Thanks, z

I still have my old set of DGV's which I ran for about 15 years. They were mostly trouble free, although I did need to rebuild them about every 4 or 5 years...so this would most likely help with the old set you have. Short of that, if I had to guess (not working with it obviously) I would start by making sure I had no vacuum leaks period. These days I have a vacuum tester so if you have one use it, otherwise its back to the old fashioned way. Still pretty simple stuff. Next, I would make sure that your carbs at set at baseline adjustment. 1 1/2 turns out on the idle screw, and 2 on the speed screw. Other than that, I found this article which pretty much is all about your problem and could really help. http://www.theautoist.com/weber_carb.htm Here's a much more detailed progression to tune the carb http://wiki.datsun1200.com/index.php/Weber_DGV_Tuning an exploded view of the carb and it's parts http://s2.pegasusautoracing.com/2008/049.pdf That's where I would start. Vacuum....if this is right, then it helps to isolate the issue to the carb, and not it's installation. From there Baseline adjustments...from there and with the help of the info in the links, you should be able to figure out what the cause is and correct it. Hope this helps... z

Was the car running fine with the duals up until these symptoms occurred? Or did you just set this car up to run the downdrafts?

Another member posted this a while back, it's a great site. You'll find the wiring diagrams (and much more) for your year car. Pdf's (very readable and zoomable). Should tell you all you need to know. http://atlanticz.ca/zclub/techtips/electrical.htm

Just thought I'd post up some pics of the camber plate install for the coil overs. I got the coilovers and plates from Arizona Zcar...and after quite a bit of waiting my welder buddy was finally ready. I took the car up to his place about 40 minutes from here, and proceeded to tear apart the struts...I'll post pics of that later. Once the strut towers were dropped out of the mounts, it was on to the cutting aligning and welding. AZcar shows a cutoff wheel being used to remove the tower cap....I like Al's method better. Much cleaner cuts with very little finish ginding required. Here's the driver side cut out, with the plate and shock gimbal.... He aligned the plates (Super Important) with a solid aluminum bar he uses as a straight edge...took quite a while to get it exact. Measuring from the firewall, as well as the core support put the bar in the exact "square alignment" position. At that point he tacked in the camber plate and checked alignment again (and again). This is a shot of the pass side being checked for alignment after it was tacked in.... Double checking the free play of the shock gimbal on the driver side before final welding... Once we're happy with the alignment, the plate is welded in completely.... Once they're finish welded, he grinds them down to a point where I can finish them smooth for paint. Once painted, it will look like it came from the factory like this.... We'll be doing the rear camber plate install this week, I'll also be posting up on the strut tower dis-assembly, cutoff, and modifications. Can't wait to get it all in, but things are moving along pretty much right on schedule...ok, maybe a couple weeks behind, but with any build...we'll count that as "on schedule".

I had a 260 with the stock setup, and unlike many I had no problems with them. Lotsa crap on the manifolds though, so it's not a very attractive look and there are much better performance choices out there. I did end up ditching that setup, and going with the downdraft Weber dual setup. I've heard plenty of people trash them, but I had great luck with them. I used a 240 balance tube (no egr), ran them with a Hooker Super Comp set of headers and wow was it fun and effortless. I will say there's a cold start issue with the downdrafts due to the "uphill" climb that the fuel/air has to make up the manifold adapter to make it to the "level" ground of the intakes. When the mixture hits the cold aluminum, condensation can occur and look out for backfiring. Once it's warmed up, it's not an issue...and for me (this would change with jetting)....the break point would have been around 52-55 degrees. Anything lower than that and good luck, any temp above that and it's just a matter of how long will it take to warm up. Easy solution to this issue is just using heat on the manifold adapters. Back in the day after I figured this out....I used magnetic block heaters. Of course they don't stick to the aluminum, but you can set them in there on the top of the manifold adapter behind the carb and in about 5 minutes bang/zoom. Now, with so many heating options a small electric heating coil like that of a heated seat, or any type of line heater would solve this. The twin setup (weber) I think looks great compared to a Holly setup. Granted, you can't get much simpler than a Holly...but as a "semi purist" it just doesn't look right to me. And plenty of non Z stuff I think looks great....and alot on this site looks amazing...but that 4 barrel setup looks to me like my old Ford truck intake and I couldn't get myself to go that route even if it was the simplest. The triple setup I think "looks" the greatest (imo) and they're awesome when tuned right. But not for the faint of heart or the less applied z owner. The FI setup you have right now is about as bulletproof a daily driving setup as you'll find. To me, it just lacks the "passion" of the other more exotic choices. My rank given two categories: Appearence, and Performance considering popular carb choices and stock FI Appearance... Triples Su's (240z style) Dual webbers 260z Flattop Fuel Injection Holley 4 barrel (sorry, for me I really don't like this look) Performance... Triples Su's Holley 4 barrel (this could easily be no. 2 in this ranking) Dual Webbers Fuel Injection 260z Flattops

Dude, is it Steam??? Cuz they've been pissing me off lately with the latest updates and protocols....Lagging like cra-z

Thanks John, makes sense. I definitely understood what Jmortenson was saying there given the independent rear. It just seemed a bit odd that I've never got any of those cars to spin two. But those solid axles do torque twist when your hard on it...so that would explain my "always" scenario. No, I haven't put it in yet. Timeline now puts the install probably around 4-6 weeks, I'll definitely let you know what I find if you haven't done one by then. Hopefully the snow will hold off so I can check it out. I've done a few calculations for RPM given certain speeds and it will be a lot different than the 3:36's and the 3:55's that I'm used to. I'm not going to do much road tripping with the car, or I might be a little concerned since I'm going to be running a loud exhaust as well. But then again I loved the sound of my 260, fully open with webers....so not sure if it's gonna bother me or not. If it's a problem I'll just swap it back, but I think the added zip will be a riot.

I appreciate the responses and the "how stuff works" link. The only question I have left really is.... If an Open Diff is most common, and the Z spins two as a result of the "equal torque" being applied to both wheels....why would say my old Buick always spin one, or my old Mustang, or the list goes on. The Z's have all laid down two, although the "Donut" test is a great example since they would lay down two as long as you were going relatively straight. The "one wheel wonder" that many of us grew up with never would spin two....and I mean never. Were they just super cheap open diffs that power would always make one slip? Just wondering, since the Z question was answered perfectly...thanks!!! Oh, and looks like I'm good...thanks for the pic example jmortenson, here's a shot of the 3:90 LSD that I've got. Thanks again guys!!!

I've searched this and came up dry, so I hope someone has an answer for me. Lots of talk about the LSD's on this site, and I read this very informative post through and through as well... http://forums.hybridz.org/showthread.php?t=114798&highlight=differentials but it doesn't answer my questions... ....with my limited knowledge I've understood there to be "one wheel wonder", "limited slip", "Posi Traction", and "spools" in rear drive cars. A one wheel wonder car will only spin one tire period (we've all presumably had one or two of these)...a limited slip car will mostly spin two...a posi will mostly always spin two, and a spool of course will always spin two. So, since there wasn't a limited slip diff it's said... (http://datsunzgarage.com/engine/ ) until 1987....why have all the z cars I've owned (and there've been plenty) spun two most of the time? If this isn't limited slip...then what is it, and why is limited slip better? What advantages are there to an LSD, if I've already got a diff that will spin up two wheels? 2nd Question... I bought an r200 3:90 Diff supposedly out of a Japanese Skyline... I'd like to know how to Identify it as such, and to Identify it as a true LSD diff but haven't been able to search out any answers. Any help (or schooling) would be greatly appreciated.

Wow! I think you're doing real well having that kind of money at 16. I'm guessing that he got tired of holding on to it....since I paid $7250 in August. I figured it was worth the money considering it has all documentation since new, was an original owner car (just months before we saw it), and was from Arizona. Not many one owner Arizona cars showing up here in the frozen "rusted" north as you probably know. I couldn't resist it, even at that price. Looking at the cars on Ebay these days, I feel very lucky to have this clean a car at that price.