Xnke

Yes...what viscosity of oil are you running and what is your oil temperature?

I don't know about you...but a 70ft-lb loss is something to be concerned about. If I had paid 3000$ for a cast-piston bottom end, and then 2500$ for a cylinder head that dynoed 70ft-lbs more at the builder than at my local tuner, I'd definitely be looking at the tuner and asking where the other 70ft-lbs went.

71C is just as light, honestly, and has a double-cone 2nd gear synchro. Might help, but will be a slower shift, I think. The dog-ring method works for all the 71x boxes, pull the engagement ring off and press-and-weld the dog ring on, then cut the engagement teeth in the old shift hub.

Or use the LS1 temperature sensor and an M12x1.5 to M16x1.5 bushing.

You need to dissasemble the distributor, weld it, then reassemble it. Or drill and tap a screw with locktite in. Wire will NOT work...not for long, anyway.

If it's an original Nissan-assembled engine, it has higher quality components than you're likely to be able to find nowadays...you can't get Nissan bearings or ring sets anymore for these. You can still get quality parts, don't get me wrong, but you really have to hunt for them. If it was me, I would disassemble and check dimensions and clearances, and if they were still in-spec, reassemble and go on with it. If they were out-of-spec, then I would do a complete rebuild. It does have nearly 200K on it, depending on the life it's had, it may be time. If the compression test was within 10%, then you likely have decent compression ring seal, so it is down to either oil rings or valve seals. Valve seals are twenty bucks, headgasket is twenty bucks, so you could be back on the road and not smoking for under 50$. Or you could drop 800$ or more on a complete bottom end, plus 50$ for the same headgasket and valve stem seals. I would order a set of the Ford valve seals and install them, carefully, and then reassemble the valve train and the engine with a new headgasket, and run it. Chances are good your smoking problem will be solved.

I know you did a compression test...did you do one with a teaspoon of oil added to the cylinder? Both the dry and wet test are needed to rule out rings without a leakdown test. Also...not every gauge set reads the same. Did you write down each cylinder, noting if any cylinder reads more than 10% (personally I go 5%) different than the others?

More than likely it is bad valve stem seals. As I said...the bronze guides don't last as long as the cast iron stockers either. Did you do a wet and dry compression test before you tore it down?

You've discovered the way that most of the older Nissan FS5W71C dog-ring boxes were/are made. Nifty, eh?

Those ports look clean enough...not sure if the valve stems have oil coating them or just residue. Ring ridge...you seen in your photos of the bore walls where the rings don't come up any higher? There is a very clear mark there. If you can catch a fingernail there, then you have a bore issue. Would be uncommon at only 180K, but certainly possible. If you can't hang a fingernail on the ring ridge, then try this Tip the cylinder head up with the valve cover bolted on with the gasket, and pour a little oil in the valley so that the valve stems at the back of the head are submerged in oil...they should have what's called "positive contact" seals on them, so with just gravity pulling, you should not get oil leaking down into the ports in any great amount...if you get any at all. Bronze guides do run a little looser and wear out quite a bit faster than the stock cast iron guides, so you will likely get a little oil. It should not be very much at all! Leave the head tipped up like this over some paper towels for 30 minutes, and then come check for oil seeping past the guides. If you get more than a drop or three, it would be a good idea to check into changing the valve seals first. A set of the fel-pro Ford 2.8L Capri seals can be tricky to put on but will not pop off or leak like some of the aftermarket stock replacement seals can.

Check for a ring ridge at the top of the bore. Has the bottom end been rebuilt previously, or is this a Nissan assembled bottom end? Yes, smoke on decel can be valve stem seals. Also it will puff blue smoke on startup after sitting overnight, that's another sign.

The big thing on the L28 is timing advance, and compression/cam comes into that. With that Isky grind, you should easily be able to run 10:1 compression if you set the valve events properly. I ran 9.7:1 with a smaller cam for several years at 36* advance and had zero pinging issues on 87 octane. Set your intake valve closing event properly, don't run it lean, and make sure you use the correct plug heat range, and you will be rewarded with a ping free engine. Cylinder pressure makes power...too much cylinder pressure at low rpms results in pinging, and too much heat in the chamber makes it worse and even more damaging. Manage cylinder pressure to make power without pinging.

Nay, look closer to home. Although, there is a guy with 96mm stroke forgings out there, for the 3.6L engines... The RB crankshaft can be pressed into service, but it requires work. An RB forging, as long as the snout and bearings are not finished, is the place to start from.

With that much cam, you should be bleeding off enough compression to not have preignition issues with proper fueling. But KEEP YOUR EARS ON! Check your plugs regularly for detonation signs until you're convinced it's safe!

Not enough compression for that cam, either...flat tops and an uncut P90A are 8.8:1, and that cam will want 10:1+ for best performance. You're right at the bottom edge of the compression ratio range, it'll run and can probably make good power, but there is still cheap power to be had in compression. Set the intake valve closing event to 76*ABDC and try it again, that cam should start pulling from about 3500 and pull cleanly to 8000, making peak power somewhere around 7000RPM or even a little higher...will depend heavily on your intake runner diameter and your fueling.

So how many folks have figured out the method I am using to get a 90mm stroke L32 crankshaft? Hint...what other Nissan has the same bore spacing, same bearing diameters, and has a timing belt instead of a chain? Some effort required...

90mm stroke can be crammed into the case with effort...

Yes, that can be (and should have already been) pulled, but you need to look at the damage it will cause elsewhere. The roof is mis-aligned, the rocker is bent upward, and the rear deck is likely warped. The next pull will be back-and-down, with a fulcrum under the rocker panel. It can cause bad things to happen, even when you only have to move an eighth inch to make it right.

More info on the pistons, compression ratio, is the head ported or just bolted on stock? Current cam info would be a big help as well. Is it a stock cam? What size webers? That torque curve is pretty nice...223HP is not terrible if you have a small cam and a stock head. I would be starting with a cam in the 0.480" lift range, but keep in mind piston-to-valve clearance! Make sure you have enough piston crown thickness to cut the valve reliefs in. Can't really give a lot more suggestion till we know what you've got to start with

Took out the valves and went to weigh them, batteries are dead in the scale. Will buy some tomarrow and weigh them.

I have a set of the -N1100, I'll check one tonight.

Do they come in 58MM???? If not...can you mod a set that large? Lemme know when yours arrive!

That's true...but they were sold through the Nissan dealerships as the "Sports Option" rods. I bought a partial set here in town about three months back...They still haven't found my sixth rod, so I may never have a complete set. I have a complete set of 6 12100-N7170, and an incomplete set of 5 12100-B2501 rods...The -B2501 PN is the FJ24 140mm rod, and was supposed to be sold as sets of 4 or 6, weight-matched and sold as a set. Both of these part numbers have bronze bushed small-ends at 23.5mm, and standard big ends, with cap-screws instead of rod bolts. You wouldn't know where I could get the 12113-H5820 rod bolts for the -N7170 rods, would you, Tony?

It is a typo...I back-checked the indicated lobe lift vs the rocker ratio, the lobe lift given is 0.288", he says he measured about 0.432" lift at the valve, that's a 1.5:1 ratio. That cam grind looks a little odd, but the cam is "very small". The lift numbers are pretty much spot on for a stock, unported head, although I would want more duration at 0.050" lift. Somewhere around 224* at 0.050" lift for a 0.430" lift cam. I would not look for more than 180HP, really...but given that you have a presumably un-ported, small-valve Maxima N47 head, 154HP and 150ft-lbs is pretty respectable!

Which is probably all you can run before hitting detonation, but it is worth the effort to fix that distributor. I would call around and see if there are any dyno shops around who can re-curve a stock distributor. I would want to see 18 degrees at idle, to 1200RPM, then ramp all the advance in by 3000RPM, shooting for 28-30 degrees total advance. You don't really need that last 6 degrees or so with the very closed chamber head when running a flat-topped piston. That assumes though, that you have flat topped pistons, and 11.25ish to 1 compression... What camshaft profile are you running? lift, seat duration, duration at 0.050" lift, IO/IC/EO/EC?