Chickenman

Dang...I missed this sale. Was looking for JDM style bumpers for my 280Z as well.

^ I made a couple of edits to my original post as I made an addition error. The important thing to remember is that you can fine tune the Vacuum canister to reflect your particular engine specifications and fuel requirements. To maximize fuel economy you want the engine just on the verge of light pinging. BTW, modern engines with Wide Band fuel control and Knock sensors can be much more aggressive in the ignition Timing maps than the ECU's and limited sensors that they had to work with in the late 70's,1980's and early 90's. Partly the reason why you have seen such advances in Fuel economy since OBD-II standards came into play in the Mid 1990's. With good fuel ( 91 to 93 Octane ) , 10 to 1 CR and a good combustion chamber design, any carburated or EFI aluminum head engine should be in the 50 degree total advance range under cruise condition. If you encounter a slight ping when applying light throttle at cruise, then reduce the amount of Vacuum advance by a couple of degrees with the limit stop. This assumes that you have adjusted your mechanical advance to be perfect. A chassis Dyno really helps there. For example. My 1986 Chevy Camaro that I used to Autocross/Hillclimb put out 420BHP and ran quite happily on the street with 91 Octane gas. ( It also easily passed Provincial emission specs with a HF Catalytic Convertor ) Ignition Timing was 12 initial + 22 mechanical = 34 Total mechanical . All in by 3,000 rpm. When I went racing ( Hillclimbs ) I would use 94 Octane as I needed every single BHP I could squeeze out of the engine. On 94 Octane fuel I could run 16 initial + 22 mechanical = 38 Total mechanical. This was set to give maximum HP and Torque on the Dyno. Vacuum advance ( Crane fully adjustable vacuum can... just like our Nissan's ) was adjusted to give 15 degrees extra under Cruise conditions. With my street tune of 91 Octane that gave me a total Mechanical and Ignition advance of 49 degrees. With 94 Octane total mechanical advance and vacuum advance = 53 degrees. Never any pinging. I would pull 22 to 24 mpg out of this 420 hp Holley 780 carbed car consistently, which was amazing. That is because of a sharply tuned car that ran a properly adjusted Vacuum advance.

Going back to Jason Gray's excellent distributor article, many people skip over the part on Vacuum advance. Don't do that. Read it carefully and then read it again. http://newprotest.org/projects/510/jasonGrayDistributor.pl Here is a very important part pertaining to the Datsun Electronic Distributors, as others have mentioned: So what does that tell us? Well lets say you want a total mechanical advance of 32 degrees ( Depends on fuel quality and other factors ) at 3,500 to 4,000 rpm. Full mechanical advance is usually all in by 3,500 rpm. Some people prefer it coming in faster, some later. It all depends on the engine, fuel quality and drive-train setup. You should check the distributor plate and calculate the numbers. IE: a 10 stamp on the dizzy plate = 20 crank degrees. Add 12 degrees initial timing and you're bang on at 32 degrees total. Now lets look at the D6K82-01. This has an 8.5 dizzy plate = 17 degrees crank advance. A fairly common number. Add 15 degrees initial timing and you have you 32 degrees total mechanical advance. Always double check the figures with a Dial-back timing light. Notice that we have not discussed vacuum advance at all. That's because when setting total mechanical advance, you musty always have the vacuum hose disconnected from the distributor ( and open end plugged of course ). So lets address that. You have your D6K82-01 dizzy dialed in to 32 degrees total advance so lets see what your total mechanical and vacuum advance will be under cruise ( light load with maximum vacuum ) . Lets see... the D6K 82-01 is a low compression emissions engine, so Nissan equipped it with a 30 degree vacuum can and low static timing ( 6 degree BTDC ). Then you came along and bumped the initial timing from 6 degrees to 15 degrees because = HP!! . Your mechanical advance curve is now good for maximizing fuel efficiency and HP, but lets see what happens when we add in the Vacuum advance. 15 initial + 17 mechanical + 30 vacuum = 62 degrees!!! Houston we have a problem!! What vacuum canister am I going to use? Simple...the original one the dizzy came with. No need to buy a different canister, just reset the limit stop on the present one. Edit: Remember that you want the total mechanical and vacuum advance at cruise RPM to equal approx 50 degrees BTDC . You can adjust that down a bit if you get pinging under light throttle application at cruise. Remove the Epoxy blob with a thin flat plate screwdriver. Just chip it away. After 35+ years I've found that the epoxy has usually gone all brittle and flaky. Re-seal with an RTV blob. Then adjust the inner limiting screw to limit the maximum travel to achieve 18 degrees vacuum advance. 15 initial + 17 mechanical + 18 Vacuum = 50 . There should be enough adjustment to handle all situations. I make a rough estimate and then do a final check with my Dial-back timing light and a Mighty-Vac. Jason Gray's article even tells you how much each mm of adjustment affects timing advance. You can also adjust how quickly the vacuum advance comes in by adjusting the outer threaded sleeve. This can come in very handy on motors with big cams. I'll post some info o that later. These vacuum canister adjustments can be made on any Datsun EFI dizzy. If it has a putty/epoxy blob on the end of the vacuum can, that's a fully adjustable vacuum canister. Lucky us.

Just to further comment on Blue's link to Jason Gray's page. All Nissan Electronic distributors have a vacuum advance that is FULLY adjustable for both travel amount and for the spring pre-load tension. Understanding how this works can really open your eyes to tuning possibilities. http://newprotest.org/projects/510/jasonGrayDistributor.pl Vacuum advance pays huge benefits on any street driven car. It is particularly important at cruising speeds where a Vacuum advance will increase engine efficiency and MPG. If you're not running a Vacuum advance on the street you are just throwing money away from wasted fuel mileage. That is a proven fact. On Race Cars a vacuum advance doesn't matter because you are nearly always at WOT. It does matter on a DD though. At cruise speed and RPM's, the engine is at very light loads and with very little throttle opening. The low throttle opening reduces the Volumetric Efficiency of the engine and the air/fuel mixture density is very low. The low mixture density with a VE of 60% ( example ) takes much longer to burn than when the cylinder is filled at maximum density ( VE 100% ) . This requires lighting off the mixture much earlier in the combustion cycle so that Peak cylinder pressures occur at the proper time ATDC. This maximizes torque and fuel efficiency. It is important to note that the reduction of VE at cruise RPM's and low throttle opening also reduces what is called " Dynamic Compression " ratio. Static compression ratio is the mathematical calculated compression ratio of cylinder volume. It is calculated using 100% VE. Dynamic Compression ratio is what the engine actually sees in a running condition and VE is a variable. This is why when you do a standard compression test, the instructions always tell you to jam the throttle wide open. If the throttle is closed when taking a compression test, very little air can enter the combustion chamber and you get a false reading. It is also why engines with big cams require more ignition timing advance at low rpm's and mid-range than a stock cammed engine. The big cams overlap period reduces the Dynamic Compression ratio at idle and low rpms' ( below approx 2,500 rpm ) and you also get exhaust dilution at idle from the over lap. Additional advance at idle is required by bigger cammed motors. Getting back to stock engines. At cruise RPM and light loads, it is not uncommon for Petrol engines to require a total ignition advance of 50 degrees BTDC. Even engines with high static compression ratios ( IE: 10 to 1 ) require this to operate at Peak efficiency. Continued....

Can't go wrong with Isky parts... Do you recall how much shorter the Isky retainers were on the bottom side?

I used to use the Nissan A -series valve seal on my cammed L-series. . The ones with the metal shell. 13207-H7210. Easy installation and gained you some room...but I can't honestly remember exactly how much. Spring retainer to valve seal clearance is something that should always be checked with big cams. Looks like these are still available OEM from Nissan. Funny enough..they are a stocked item with most Nissan " Forklift " dealers...

Edit: Because they may not gain you " enough " clearance. You can gain some clearance by using the A-series Nissan metal shell seals, over the original L-series seal with all Nitrile body construction ( 13207-21000 ). That can still limit your valve lift to around .480" if you use the stock retainer. I've seen Datsun L-series race cams with well over .600" lift. You may have to machine the guide, machine the bottom leg of the valve retainer or get different retainers depending on components used. .120" clearance at full lift should be more than enough. Note: Post edited to clarify answer.

Valve lift over approx .460" will result in the bottom of the stock spring retainer hitting the top of the valve seal. You shorten the valve guide to prevent this interference with high lift cams. A common Mod to all Datsun L-Series engines. The other way around this problem is to use aftermarket spring retainers that have a shorter " leg " on the bottom side. Isky makes these in steel 1624-ST(12) and Titanium 1624-TI(12)

Regarding Fuel tank. While the car is up on a hoist and you've drained the fuel tank, it would be a good idea to check and/or replace the main hose to the fuel pump and all other vent hoses. The main hose to the fuel pump is quite large. 13mm or 1/2" as I recall. Add a METAL inline fuel filter between the fuel tank and the fuel pump. A Fram Gxxx ( I'll find the correct number later ) works well as a Fuel Pump pre-filter. I do not like using a plastic fuel filter in this area. A rock can fly up off the road and shatter a plastic fuel filter

Have you snugged the Fuel line clamps yet? Better to do it sooner than later. There are a lot of fuel and emission hoses in the engine compartment that can leak. Check the hose clamps on them all. Fuel injectors, FPR, Fuel filter.. check all of them. Inspect the hoses carefully for any signs of rotting or cracks. If suspect replace all of the relevant hoses. Make sure that you get good quality FUEL INJECTION rated hose ( it should be re-enforced and clearly marked as a high pressure Fuel hose. Be sure to use new Fuel Injection clamps. While you're at it, put the car up on a hoist and check around the rear fuel pump and fuel tank with the engine running. I've seen leaks from FI pumps at both the O-Ring and also the electrical contacts. I you see any weeping at these points, replace the pump. Check the sending unit as well. These can leak from either a old O-ring under the retaining ring and also from the Electrical contacts. The electrical contacts have a small o-ring underneath to seal them, and this dries out with age. As new sending units for the early 280z's are next to impossible to find, you can repair the electrical contact leak. Remove the sending unit. ( Drain the gas tank and observe all safety advisory's ) .Clean the areas around the electrical contacts with a SS or Brass wire rotary brush ( Dremel or similar ). Then apply JB Water Weld around the connections. This product is magic and seals water, petrol, diesel, hydraulic fliuds and most chemicals. It will even cure underwater. Ordinary JB Weld will eventually be dissolved by Gasoline, but JB Water Weld will not. It's product description specifically mentions it's use for repairs of Fuel Tanks and Oil Pans. I used it to repair the weeping electrical connections on the Fuel Sending unit of my 1976 280Z when I could note source a new one or a good used one. That was 6 months ago and so far I have not seen a single drop of fuel from the Fuel Sending unit. Of course I installed a new retaining ring and O-ring. BTW, Nissan still carries those parts t and they are cheaper than MSA or any other supplier.

Did you re-adjust the slot opening amount as I suggested? You should be able to loosen the lock nut and adjust the slider stop. Edit: I'll have to get going and put mine on. It's fairly cold out now, so it should be a good test. Been busy sorting out my Audi... which if you've ever owned a German car, means it's a constant battle

As mentioned, the Valve springs are new OEM Nissan 13203-F2000 outers and 13204-23000 inners. The 13203-F2000's are a superceded part number from the 13203-E4100. Does anyone know if the F2000's have more spring pressure than the E4100's ?

If you've kept the factory AC plastic vacuum reservoir tank and the FICD & A/C magnetic vacuum valves it should be easy. The Vacuum tank has a one way check valve in the line just before the Tank ( underneath the relay cover ). Just connect the AC vacuum feed line to one of the legs on the Cannon manifold. That will cover your vacuum operated Heater/AC dash pots. If the manifold does not have a vacuum port, drill and tap one for a 1/8th pipe thread. The heavy pulsation of connecting a vacuum source to one leg on an ITB manifold does not matter in this case because the Vacuum tank will act as an accumulator and the 1 way check valve will prevent vacuum from draining from the tank. ITB manifolds will actually pull a very strong vacuum signal...but with pulses. This tends to screw up a distributor vacuum advance which is connected directly to a manifold leg, but should not affect the Factory AC vacuum reservoir system because of the Reservoir tank. To run a Vacuum advance properly with Triples, you have to build a manifold log to dampen the fluctuations. . If you find that you need an AC throttle kicker, it might be best to toss the factory Vacuum dash-pot kicker and utilize an electric solenoid that extends when 12 volts is applied. You can easily splice that into the AC clutch 12 v line and fabricate a bracket for the Triples. Modify the main linkage rod with a Tab, so that solenoid " kicks " the main throttle rod when the AC comes on.

Thanks John. That's pretty much what I figured, which is why I'm imposing the 6,500 rpm shift point. I'll set the rev limiter to 6,700 which gives me a bit of room if I have to stretch things. We did re-use the old 9mm Rod Bolts and Nuts. So that does concern me a bit. And we did not balance the assembly. Normally the factory balance is pretty good and if memory serves me correct, you can re-use the Rod Bolts once on a non-race engine. 8 mm bolts would scare me re-using them. 9 mm not so much. Am I correct on this? This engine is pretty much just a nice stock rebuild, with the exception of an HP Cam. Valve train is all new ( Springs, valves, valve guides etc ) with a fresh 3 angle valve job. I figure there's no point in twisting the bejeezuz out of it. The original engine builder is a great guy... but a bit of a story teller. Last thing he told me after the engine break in was that the engine should be good to 7,400 !! Yeah right I just smiled and drove away slowly... Richard

It's been a long time since I've run an L6 engine, but I used to race L24's many, many years ago. Right now the car pulls really hard to 6,500. What is the safe engine Redline on an L28 with a stock bottom end? I've have a freshly rebuilt L28 engine with a 280 duration .460 lift cam. New Nissan factory valve springs ( 13203-F2000 Outers and matching Nissan inners ), Doug Thorley headers, 2.5" custom exhaust. Factory balance job. Stock rods. Stock Flat tops. I will be autocrossing this car a bit next year and maybe running some Track days. I used to run my L24's to 7,000... but on the L28, I'm thinking of using a 6,500 RPM max shift point with Rev Limiter ( Crane Hi-6S ) set to 6,700 rpm. Shouldn't be any reason to go above this should there?. Car will likely have a Mega Squirt 2 or 3 system by next year.

I've owned several Camaro's that I've Hillclimbed, Autocrossed and Track Dazed. All had HEI ignitions at one point and all used the stock HEI module. Engines were all in the 10.5 - 1 CR range and all made in excess of 420 HP. I could run to 7,000 rpm with no problems at .035" plug gaps. Not on the factory coil though. I used Accel internal coils and Blue Streak HD caps and rotors with Brass contacts. Also, on an HEI distributor you absolutely MUST replace the high resistance carbon button that connects the coil to the rotor with a low resistance bronze button when using an upgraded coil. The factory ignition coils and the high resistance carbon dizzy button are the real weak points of HEI distributor... not the module IMHO. Having said that, I did update the HEI distributor with a Crane Hi-6 CD ignition and LX-92 external coil. Plug gap was increased to .040" and engine did idle noticably better with the Multi-Spark feature. Seemed to pull harder as well...but I did not do any comparitive Dyno tests between the different ignition systems. Butt Dyno and emmissions testing seemed to show an improvement though. BTW... I love David Vizrds's articles. Great engineer.. but he does tend to pitch the " Product of the moment" . But really, any author of Automotive books does the same thing to different levels.

I remember the same gasket between the spray bar and cam towers on my 1971 . It was definately factory. However, if my aged memory serves me correct that gasket was not available separetley. It only came with a new Spary Bar. Had to install a new one on my 71 240z and I remember that the new Spary Bar came with the gaskets already glued on.

^^ Sounds like the slide stop needs to be opened up a bit. Or you could re-adjust the air bypass screw on the AFM ( Mixture adjustment ). The slide opening and AFM mixture setting have to be matched during warmup. If the CFM flow of one AAR is different from another then the idle mixture adjsutment on the AFM has to be adjusted. FYI: FSM says idle mixture on 75 and 76 models cannot be adjusted...but that's not 100% true. Depending on Model of AFM it may have an aluminium plug in it ( " Tamper proof plug ) .. but it can be easily drilled out and removed. Later models, with Catalytic convertors, had no plug or a rubber plug covering the idle mixture bypass screw.

Isky still makes some L- Series grinds. ( L-6 and L4. Also A-Series ) http://www.iskycams.com/onlinecatalog.html Isky cams.bmp Isky cams.bmp

I couldn't get the Edit function to work in my posts before. Fixed now. 10 Micron is fine for Petrol EFI, but it is not the only determination. You have to watch the flow rates. Pleated Paper element filters have a high surface area which enables them to filter out very small particles while maintaining proper fluid flow rates. That is something that must be considered when purchasing any filter. Most filter manufactures now use a standard called Beta Ratio Testing: This is a good Tech Article from Baldwin Filters ( One of the largest filter manufacturers in NA ) , Click on the PDF's at the bottom of the page: Baldwin Filters | Product Highlights Actually SS Fuel Filters ( good ones ) now come in 1 Micron sizes which is more than adequate for Petrol EFI. But decent ones are not cheap. SS meshEFI filters for petrol with adequate filter area is going to cost between $125 to $160. And then there's the question of efficiency rating, IE: if the micron rating is rated " nominal " or " absolute ". It's a big difference as per the article above. Canton makes excellent products. but I have no idea of their efficiency rating: https://www.cantonracingproducts.com/product/25-910/25-910----CM--15-FORD-EFI-INLINE-FUEL-FILTER-OE-FITTINGS/ IMHO, there is absolutely nothing wrong with paper element filters. As long as you get quality products..... AND stay away from fuel with Ethanol contents higher than 10%.

For some reason the " Edit Function " is not working properly and I can't edit my above post. Member HR369 mentioned that you can get SS mesh filters for EFI systems as well. Edit: But decent ones are not cheap. Expect to pay $125+ for one of decent quality and capacity. BTW.. biggest Hype job and marketing ploy of all time is K&N Air filters. Yes they do make horsepower, and they're really good as a filter on things like ATV's and Motocross bikes. Mainly because they don't fall apart when wet and will filter when covered with mud. And they're great for wringing out that last HP on a Race car. But as an actual " FILTER " of small particulate matter, they are terrible. You will never EVER see a Cotton gauze type Air filter on any manufacturers engine...because they can't filter the really fine stuff. Same with oil filters. Paper ( actually a Cellulose fiber ) is a very good FILTER medium. Here is an Independent study various air filter mediums. K&N and foam filters turn in very poor performances in actaul filtering capacity. Summary of testing: Air Filter Study Completed!!!!! - TheDieselPage.com Forums Link through Nico.club of actual Test Data : K&N Air Filter Review - Debunking the Myths (and why OEM is better)

Paper element or cellulose filters are actually a very good filter medium, both for fuel and lubricants. Manufacturers of everything from Mopeds to Locomotive engines have used them for decades and millions of miles for good reason. They are effective and are cheap to replace. Stainless mesh steel filters made for Diesels can catch the bigger stuff, but they can not catch the small micron stuff that can plug Petrol fuel injectors. Orifice size on Petrol injectors is usually much smaller than on Diesel Injectors. You can use a Stainless mesh filter as a pre-filter for fuel and this is their main function ( particularly on Diesel engines ) , but it should always be installed with a paper element or synthetic fiber filter after the SS mesh filter. Diesel engines usually have multiple filters in the fuel line, including pre-filters and water filters , because the fuel tends to contain more contaminants than Petrol. This is mainly due to methods of Transportation and storage, in remote places like Logging camps and Mines The real problem is quality control with the flood of cheap aftermarket products from off shore. Also, product lines that used to be good ( IE: TRW, SKF, Sealed Power ) our now made Globally and quality control suffers greatly. Best advice is to buy your filters from OEM. Got a Nissan, Honda, Toyota, Ford, Chevy, Audi whatever.... buy your filters from the Dealer. You pay more, but OEM filters are usually VERY good quality. Edit: You can get small micron ( 10 Micron or less ) high quality SS Fuel Filters for Petrol...but they aren't cheap. You also have to watch the filter area size. Many of these filters are designed for Race engines and require more frequent cleaning than a Paper filter

I'm kinda lucky here as British Columbia Canada is a hot bed for Datsun 510's and to a lesser extent Z cars. At least three of our major Nissan dealerships have Parts Departments staffed with ex Datsun Racers and they are all still enthusiasts. As a result they tend to keep in stock a healthy supply of maintenance parts for our Vintage Datsuns. They also have no hesitation in tracking down obscure parts, be it from the USA, Japan or wherever. It's a really nice community. I'm one of the old timers who worked with these guys way back when, in a Galaxy Far,Far Away It's also nice to see that the old guys, who are all Parts Managers and ready to retire, have trained a new group of younger enthusiasts to take over. I did a cruise this Summer with a local 510 Club ( The 510 Realm - Index page ) and we stopped off at Local Dealership ( WestCoast Nissan ) on the way. We had half of the Sales department, Service Department and ALL of the Parts department out looking over the cars, chatting and taking pictures. Good Times

Pretty sure that the Factory Nissan F/F do not have a sticker on them. Information is silk screened on. I'll take a closer look at my BNIB Nissan FF a bit later and post pictures. Better yet I'll pull my old FF off and cut it apart to compare. Pretty sure it's OEM Nissan as well. Ethanol could certainly be the culprit, especially in concentrations above 10%. All manufacturers usually have warning in the owners manual to avoid ethanol concentrations of more than 10%. Even to this day it will void most manufacturers warranties. Only exceptions are Flex Fuel cars which are designed to run on E85. These have specialized components designed to handle the nature of Ethanol. Note: BNIB fuel system parts from Nissan, Honda, Ford, GM etc etc have been redesigned over the years to handle up to 10% Ethanol. This includes older models such as the 240Z. However, if you happen to discover a Vintage supply of NOS from Datsun or Nissan, they may not be have the revised materials. Anything in original " Datsun" packaging would certainly NOT be made revised materials. ( I was a Datsun/Nissan dealership partsman form 1974 to 1992 )

I noticed your car is a 1976, same as mine. Do you have the Federal distributor with the two sets of coil pickups or the California model with only 1. Sometimes the pickup coil will go bad and will work intermittently. If you have a 2 pickups in the Dizzy and you lose ignition spark you can do a quick switch of the coil pickups to test. The " advanced " pickup ( Secondary ) is only used when the engine is cold. The " retarded " pickup ( Primary ) is used when the engine is warmed up. There is a 3 way connector just above the Ignition coil. If you suspect that the Primary pickup coil has failed, you can switch the leads around at the 3 way connector and run the car on the Secondary pickup. Really the best thing you could do with a 1976 is to replace the distributor with a later model ( 79 - 81 280ZX ) that uses the E12-80 module. BTW, Rock Auto has a great deal on re-manufactured 1979 280ZX Distributors. A-1 Cardone ( a good brand ) for only $90.79 + $15 core charge. Great deal!! Rock Auto Part #31619: Product Detail