240260280z

Yeah I measured 45 seconds on my 280z after it sat for the winter in storage. You can change rockers as long as the surface is smooth, the curve is normal, the alignment of the cam interface is parallel with the lash pad interface AND both are in line. It is best to use Nissan rockers rather than after market ones.

You can dial back the idle enrichment screws to get a good a/f at idle and have clean plugs when idling. But if the fuel level is too high or the jets are too big then once off idle, the car will still be rich. Try a few plug cuts at different loads to see what plugs (a/f) is off idle: 1. Cruising 2. Accelerating up a long hill at WOT. As the guys mentioned above, if your distributor is not advancing, the fuel will burn later as it is leaving the exhaust. I don't think this will blacken the plugs though... but your exhaust will be very hot and may glow at night.

There is a restriction in the oil passage at the top of the block that limits oil to the head. The oil in the head just oils the cam bearings and the rockers. You will just take a little from the cams by enlarging. I can send you a rocker if you want to replace that one.

Yup: http://forums.hybridz.org/topic/58658-pistiondeck-height-misinformation/?p=536534

Help. For a stock L28 engine, the piston pops out of the block but the AtlanticZ and OzDat engine planning tools do not match!! I looked at my FSM's to double check all numbers: Connecting Rod Length: L28 connecting Rods c-c 130.35mm in FSM's Honsowetz, Monroe, and on-line engine calcs give 130.20mm (so this is an error but not enough to make the model fit the real world.) Piston Compression Height: Not in FSM's but it is 38.1mm everywhere Crank Stroke: 79.0mm in FSM Still, with the con rod adjustment I get a piston above deck at 0.08mm and OzDat tool gives 0.06mm using the shorter rod data. Real world for L28 is ~ 0.584mm protrusion of piston above block (nearly 1 order of magnitude higher!!!) See picture at top. It seems to point to this question: Is the block height correct at 207.85mm /207.87mm /207.90mm? It would seem that the block height needs to be ~207.37.... did someone write a "3" and read an "8"? The only source I can trace so far, for this value is 207.85mm in Tom Monroe's book however he has the rod length that is shorter than the FSM..... help

Your problem seems to be too much fuel. 4 & 5 seem less rich. Do you or a friend have an air-fuel measuring device? Quick and dirty first step would be to lower fuel level if you do not have leaner jets. You could also get hotter plugs (5) rather than (6) heat rating.

Yup! The firing ring.

Looks like we will have a new member in our club soon. What a nice guy! Even more impressive is that he has driven his Z across North America many times over East West and North South and diagonally! Looking forward to seeing your Z!

Check for VIN in this list: https://web.archive.org/web/20120920004831/http://www.editgrid.com/user/mlwilliams/Z_Car_Registry

The carbs seem to have an issue. If you could take a photo of all plugs together, we could see if it is just one carb or all 3. Check fuel levels in carbs too.

Can folks please add accurate HG compressed and diameter measurements to this thread. I have scoured the net for many data points but there is a lot of variance so Id like to start again in this thread to improve the accuracy. Here is what I have collected: MFGR_____COMP_____dia NISMO____0.60mm___??? Ishino___1.00mm___??? Nissan__ 1.14mm___??? Nissan___1.20mm___??? Nissan___1.25mm___??? Felpro___?.??mm___88.9mm Felpro___1.10mm___??? Felpro___1.15mm___??? Felpro___1.20mm___??? HKS______1.00mm___91.0mm HKS______2.00mm___91.0mm Tomei____1.00mm___90.5mm Tomei____1.20mm___90.5mm I measured the 88.9mm Felpro on a spare I have. Most state 89mm. _____________________________________________________________________________________________ Some oval shaped early L24/L26 gaskets are also mentioned but I omitted these as the volume would be difficult to calculate without knowing more details. FYI: part number 11044-N4221. Stamped with the Nissan logo with the code NRZ 46F. NRZ stands for Nippon-Reinz made in Japan. oval ring measures 89.5mm x 87mm features the same water passage holes that original (1971 E31 240z) head gasket had.

Exhaust popping is usually too rich or retarded timing. First verify timing marks: Check piston 1 top dead centre with the mark on the damper pulley. Also have a look at exhaust and see if it is spitting soot or stinky like rich fuel burn.

For initial it is just the timing at idle (800 to 1000rpm) using the timing light. Do you need to set up the carbs too?

Try 15 degrees initial timing with no vacuum advance. Don't go over 38 at max. Do you know what the mechanical advance is on your distributor?

Here are products. http://www.mgchemicals.com/products/protective-coatings/conformal/ You could melt wax over the parts too as a quick and dirty,

Hi All, I have revised the engine planning tool on our club's website (attached). Please take it for a spin and if possible, provide corrections to the data and also suggestions for more data. It is attached below. You should be able to save to your desktop and open with your browser. FYI just type in the green blocks if you want to manually override any value. Philip S30 Engine Modeller V2 Beta 1.html

Yup. I'm planning to start building some Z motors. We have quite a few in our Z barn so if the 88mm piston works out then it should be a reasonable build. The race shop that will do the machining has an engine dyno so I'll get some benchmarks.

Some pictures of a 71 and 73 here. http://www.classiczcars.com/topic/40844-1971-240z-license-plate-lamp-photos/

I bet it was painful! btw I have a mustang TB for you. Want me to mail it or wait until you and Rene visit us or we go there

you could coat it with polyurethane or silicon to seal it.

That should be in every automotive and aerospace welding manual. No one will forget it

Kurby, CCA are just making their first L28 plate next week. I may purchase it. Steve yup the machinists have measured differences with and without the plate installed. Newer techniques even pump the block with hot water to operating temperature. I plan to do quite a few 88mm and 89mm over bores over the next few years and sell some motors so it is a needed investment. ZH, for the head, the cam can be relieved by the tower bolts when it is torqued to the block. Not much else can be done w/o a long boring tool and boring new towers when installed on the block or over-boring and sleeving existing towers. Yup BHIP are très cher ($$$$)

~500-600 locally. I'm looking at one of these ~450 and probably better made: http://www.ccaracing.com/product1.htm

I think you will be ok with temperature. Just let it cool between hits and make sure the electrical path is not through the bearings.

Diving head first into a few motor builds. Trying to do it right. I figured I'd ask around before approaching a machine shop. Thanks!