Tony D

The reason for the relief valve is that total flow mapping in the ecu stops at an equivalent of 10psi. If you go into boost below 3500rpm, the vane in the AFM is still in play, but not for long. That is where the relief valve and knock sensor come into play with the timing...on boost below 3500. So by a flow calculation the ECU "knows" you are in boost, but is only programmed to 10psi...really for air density compensation on a cold day more than anything else. If you have a MAP based system (Megasquirt) then the delineation between boost or N/A is easy to see, but on the vane type it's kinda nebulous....

I'm in NJ right now, but live about 20 min north of Temecula. E-Mail me and when I get back next week maybe I can make some time to get with ya nad figure it all out. I am way behind with house work, but maybe some phone stuff will work---I do have a stim we can plug into it to eliminate the box as a cause, though!

"i am trying to avoid buying an entire parts car b/c that is a lot more money than just buying the motor. " Beware of the assumptions you make, as this one is FAR off base! I have spent $100 for a COMPLETE ZXT in Lien Sales, and have NEVER paid more than $475 for the whole vehicle. There are plenty of rusted, rolled, crashed ZXT's out there CHEAP to choose from... Most engines bare without loom sell for more than 2X my average whole car purchase: $200. Watching internet boards and E-Bay is probably your best bet at this point of the game---but you will pay almost as much for a "claimed running" setup there that you will for a wrecked or rusted ZXT. Buying the car allows you to get it running BEFORE you do the swap---an IMPORTANT consideration.

Yeah, the L-4 is a very common swap. And not only L-Series, just about any Nissan $ banger has been swapped into there: SR20, FJ20, L20B...

Beware of the myth that forged pistons cure all! They will break just as easily as cast when confronted with the forces of detonation! Fix your detonation, find it's cause, THEN make the change to forged. Otherwise you may be withdrawing far more funds from your bank than you ever thought you would spend on "bulletproof pistons"!

I know if you hit the rev limiter, and you have the retard set to 5ATDC, you can get full boost at just off idle. You can also get the turbo glowing red hot, overheat your engine, and melt the brazed joint on the turbo oil inlet, causing a dramatic oil fire. Don't ever get PO at the system and hold your throttle flatfooted while simply adding gas under boost at low rpms without watching the turbo.......

Got to agree with GrayZee on his last post. Many of the factory brainwashed technicians will have no idea about what is going on in a serious high performance application. For instance, while the knock sensor may have some effect on timing, and his anecdotal evidence of rapping a hammer on the block affecting timing (hey, you can SEE IT) he misses th point that the stock knock sensor is SHUT DOWN over 3500rpm where the engine's ECU goes on the open-loop pre-programmed "full power mode". It's out of the loop there, what they have it for is BELOW 3500, so you don't get tip-in throttle knock in light cruise to boost transition like interstate passing uphills or gradual grades when running cheap gas. That is FAR more common thatn knock under boost in the STOCK form, and FAR more likely to KILL the engine in a STOCK setup... So beware what the stock application guys tell you---lots of times they are a valuable resource, but many times, it's only from observation, and absolutely no training or factory engineering support to back up their observations. (Meaning they can tell you what it DOES, but unfortunately not WHY---and the WHY is far more important to understanding the workarounds.

not "choke" cables, "starter system" cables...Unless you have teh flat top HIF6 smog carbs---they have a real choke plate. Using an appropriate 10mm drill rod, you can make the upper linkage and use a standard Mikuini or Weber downlink and heim joints to connect to the stock piece between the carbs. From that fabricated upper bar, you can install a clamp on throttle quadrant, and go throttle cable easily. Look in the linkages section here for what you need to make it up, you should be able to get drill rod from an industrial supply house locally. http://twminduction.com

I have seen throttle cables and the quadrant attached to the upper portion of an SU linkage to use it that way. Good Luck!

You DO NOT need the cylinder heat temperature sensor! Plug that connection into the N/A water temperature sensor in the thermostat housing used for Coolant Temperature for the N/A ECU and it will work juuuuuust fine! Been there, done that! If you have access to an 81 CAS unit, you can mount it externally along with the pulley, and use IT on the later wiring harness, and simply install the 81 distributor or lock your N/A unit down for spark distribution duties.

"One of the reasons I bought a preassembled unit is so that I wouldn't have to buy a stim." Well, now you see FIRSTHAND why most people who built their own units tell everyone to buy a Stim! It's the ONLY thing that will tell you in about 30 seconds or less, if your BOX is bad, or if it's SOMETHING ELSE! Bet you would kill about right now to KNOW...

Add an Accusump! Cheap Insurance, and you can prelube that hicomp monster before putting a load on it.

But if you have three donor LD28's sitting in your shed, you start to wonder about whacking off the shaft of a drive with a perfectly good drive tang, now wouldn't ya? I would probably use a lathe to part it off nicely anyway, so it might take me more than 5 minutes, also...

J, I autoX and do track days also. I would not be without an accumulator WITH my baffled pan. Either without the other is ASKING for trouble! That was what I was recommending in my above post. One turbo was all it took to convince me about that. I will not even hard street drive corners in a turbo without at least a 1/2 qut accusump unit in it! Plus, prelube is a neat feature...

it's a factory part that drops in without modification...

Uh, why do I need to? Jeff P did it, and had 23/23 as I posted above. I will ultimately be running his setup turbochargerwise on my black car using a standalone EFI system, so given I have seen his testing setup I trust his numbers.

Generally, this is the case as you stated. The general rule of thumb is 10/1Krpm, but recently with bearing coatings some have been going as low as 5psi. Depends on compresion ratio, and if you have an accumulator. I would get an accumulator, baffld oil pan be damned, $100 to provide that extra 1qt of pressurized oil just in case is well worth it IMO!

WOW! 2:1, 1.8:1? My training said something on the order of between 3 to 5psi more than what you see in the inlet manifold. Having a multiple of boost seems like a VERY undersized turbine wheel...

While that lockwire job will not cosmetically comply with NAVAIR 1-1A-8 or 1-1A-15, functionally it will do the job. The bolts are in close geometric configuration so single wire "loop style" securing is acceptable... This isn't an F-15D APU or CGB...

The Return elbow INSIDE the fuel tank is where the EFI return lines clog! Many times you can rooter it out using a piece of brazing rod cut to have a sharp spade tip to act like a drill to poke through the swarf in that elbow. While the return line should NOT have any appreciable pressure in it, it MUST still have full pressure rated softlines and appropriate clamps as John C said. I have seen 100psi in the header, and then the return line burst AT THE TANK spraying fuel all over the muffler... Nice, huh? My bet would be the elbow inside the tank is where the obstruction lies. Easy way to check: pull the line off at the tank and see if you get freeflow. If so, I lay money you can't pump into the tank through the return line connection! Good Luck Rootering!

I know JeffP did on his last-before-this-build-turbo setup.... (LOL) My recollection was that Exhaust Manifold Pressure (measured at a tap in the spacer before the turbo) was 23psi at a manifold pressure of 23psi, from 3000 to 7000rpm. Below 3000, I don't recall if he measured that. This was very good.

The pins are available at any good industrial hardware store. I can get them at McFadden Dale Hardware in Corona in their Metric Fasteners Section. If you can extract one fairly intact, you can measure it, and order them by the size. They are a standard metric Pin Size. Sorry, I forget the dimensions, but they had several hundred at McF-D there in Corona. The flywheel has no step, it is blanchard ground true across the face---the groove cut in the face is the "use limit" for a stocker. REMEMBER TO PULL THE DOWEL PINS BEFORE YOU SEND IT IN FOR RESURFACING!!! I actually got a flywheel back with the pins ground flush!!! I got my money back on the resurface/lightening ($40) but we agreed that IN THE FUTURE I would remove the pins before bringing them any more work... I made a funky Clock for the shop shed... LOL

Hit the dyno with 280Zone and rip a run off his time.... LOL

"Cam oiler only came on 240z's, N42 is from a 280z." Better qualify that statement to "US or North American Specification Vehicles" I have an N42 headed L28 from a Nissan Cedric that has the cam oiler spraybar. The JDM L26 we installed in my buddie's Fairlady also had the E88 and a cam oiler bar. When it threw a rod, we snagged a 75 Cedric L28, and it tooo had the spraybar. My understanding is the drilled cams came in 77-78 vehicles. This seemed to jibe with non-US market junkyarding as well.

it doesn't matter. The position of the CHT reads temperatures higher than a CTS---at least using my engine as an example. I believe Nissan used the rearmost positioning of the CHT sensor on later models because the thing heats up faster, and puts the car into closed loop quicker, as well as gives a "hotter" reading for the fuel curve. I use the CHT because that is what I had in the car, and later got a thermostat housing so I could switch from one to the other to see what the difference was...