Tony D

Could be a loud "WHUMP!" could be something that sounds like a hammer banging on your engine in rapid succession---all depends on the turbo and where it is on the compressor map when you surge it. In many cases people with these "hard dump" BOV's are getting a sound much LIKE surge because they are very near lthe surge point. A BOV should make a "sigh" when relieving the pressure. Letting pressure build to a point and then dumping it is running a pressure spike close to surge before dumping it. The bigger the compressor section, the lower it sounds. It can be bad, very bad. In the old days, one good surge at full pressure could snap the blades of the compressor causing a big mess! To witness Garrett's test cells testing compressors it makes someone like me cringe. But happy at the same time, since I realize casting and blade designs have really greatly improved their strenght and integrity...

Ahhhh... And to think I spent nearly the last two months in South Jersey (Edgewater Park and Moorestown) and I only saw a silver Z32 and a Red Z31... Where were you! LOL Good to see someone has hearing!

Yeah, that is a welded and ported head, same as I have sitting out in the shed. This is the kind of work they do in Japan...

I would say to get your cousin's detonation problem under control before changing to Forged Pistons. The only difference will be when you blow the forged piston, it will cost more to replace. Stock L28ET pistons are pretty durable, as a re stock head gaskets, when they start blowing, it means DETONATION about 99.99999% of the time...not weak parts.

An O-Scope tells all on them! The pulsewidth waveform from the 81 CAS is identical to the one from the later CAS unit in the Dizzy area. Wire power from the battery to the wire with 12V---make sure you have good power there. Then make sure your pullup resistor is connected good---mine fell out causing some bad stuff. You should get a cranking RPM signal if there is a pulse coming out of the CAS.

Pretty much, but I used a three wire heated sensor from an 87 Z31. I prefer the heated three wire unit over the single wires units because they reliably give a switching narrow band signal at all operating areas, so you can run a wider Closed Loop Narrow-Band parameter---keeps the engine operating near stoch longer, giving better fuel economy in town that provided by the standard single wire unit, which usually cools off pretty quick once below 2000 rpms. That is if you run a Narrow Band. If you run Wide Band, you get even better economy because you can set off-stoch parameters... And you need a Pot style TPS. Not a switch. I used one off a 91 Sentra with an SR20. I liked the TB better than the one everyone else seems to use with the longer shaft. This SR unit bolted on and with one spring and quadrant change accepted the stock 280Z bellcrank bolt-on.... But it's not a "balck box" that looks like the old TPS, either, it's something with a flat-key drive and a grey connector.

I/C means different fuel and spark curves... Start tweaking, the power will follow. Piping size only matters as a function of volume being filled...and I/C adds volume, too. A compressor wheel that flows more will fill that volume faster, along with a proper dump valve (BOV) that will keep Turbo RPMS up allowing proper on-boost repressurization after a drop-throttle event. You changed the air density and temperature, chances are you will need more fuel and can run more spark, also. This will help boost performance. Boost Threshold should not be affected that much if fuel and spakr is correct.

I talked with a local Dyno Operator and got the O.K. "to bring my own fan" since they only had a puny air mover on a pedestal stand. I loaded up an old stripped down SWAMP COOLER fan. It was a window mount unit, so had legs and a discharge oriented the right way---I made a duct to go to my G-Nose and slid it up to the front of the car and turned it on High. This was some big honkin fan! It also helped that I resized the sheaves to max out the amperage the motor turned, so I was getting something like 5500 cubic feet a minute out of the thing. It worked really well, and cost me scrap parts and a $5 belt from Home depot. The dyno operator liked it so much He gave me two free hours if I let him keep it! So he kept it, and then went bankrupt... LOL Maybe he didn't have the best business head. Anyway, in the southwest old LARGE whole-house swamp coolers are a KILLER source for a high volume cooler with an output duct size that almost exactly matches the frontal area of a Z so making a directional duct is relatively easy, and you don't have to screw with so long in between runs waiting to "cool down". Mine was critical since we wanted to do some "hood down" runs to see if some heat shielding was going to work. It also gave me (roughly) the same airflow I figured I would be getting at 60mph, so it made it easier for some load point work that we did programming the ecu. It seemed to really keep the car decently cool---far longer than the stupid pedestal mounted fan would have done----which basically blows air on the engine and the dyno operator to keep him from sweating too much! Just a thought, you might want to try that...

Kentucky Z's? I know there is at least ONE yellow 280Z with an L28ET prowling around Lexington, on the south side of town off "Circle4" if I recall. Guys name is Wayne. I stopped by his place when I was doing a job over in Huntington WV and had a day to kill. So there are three in Lexington. Like Musketeers! My vote for L28ET swaps is simply because I have 5 engines in my sea container, so putting htem in something is easier than getting a V8 lums from something else.... Though finding a wrecked, complete Q45 or Titan might HEAVILY sway my choice of mill for the next project car. High-Tech V-8's are cool, a 1957 era 350 fits better in a Vega. Been there done that. Now a Titan motor in a 67 Camaro....THAT would be a swap to consider! Debut at Super Chevy Sunday...

"any choice drill bits to use, names to look for, since i can't say off hand if i've ever seen bits listed by diameter as small as .060?" Well, if you buy a Rochester #60 Jet, and simply tap the bottom of a threaded NPT(BSP) to AN-4 Adapter you don't have to worry about the orifice drill, do you? And you can change orifice size for about $.75... As for the line size, I was advised -3 was a better choice as it was .187" ID, almost identical to the .196" line that Nissan Supplies. One other item to think about is if you are feeding a -4 line straight through a -4 adapter, you basically have a .250" hole in the oil system blowing back to the sump. This can cause oil starvation in hard righthanders. I have lost a turbo in a hard right hand sweeper, passing under boost. if you drive hard, and do not run an accumulator for oil supply you are on borrowed time on anything but a ball-bearing turbo! They WILL trash in an instant from that air bubble travelling through the line! A large line---just like when going to a gauge, transmits a pressure drop IMMEDIATELY to the turbo. When I set up the restriction on my old Corvair (and the VW for that matter) the restriction was placed AT the turbine supply fitting, using the larger -4 line as somewhat of an accumulator, full of pressure right up to the turbo. Most Industrial Stationary Turbo Machinery will run your restriction as close to the point of use as possible to minimize effects of pressure fluctuation, and keep a steady stream of cooling oil on the componentry while at speed. Using a -4 Feed Fitting you can thread the "cone end" and stick your jet in there, also! The spool up differential is plotted in a lab on a scope trace---chances are you will not see it in seat of the pants driving. It IS a concern when designing the oil supply system for the turbo, though. It is measurable, and only mentioned because it indicates the excess oil is COSTING horsepower to turn meaning the exhaust turbine is roking harder to turn the compressor than it needs to. Remember Nissan is betting that the line will get coked up and restricted through owner neglect---which is why they called for replacement of the oil supply line at EVERY turbo changeout! Coking in the supply line has trashed more than one turbo, and is kind of a built in restrictor after about 50 to 75K miles of operation of a careless operator! On a -3 line, a restrictor is not nearly as important as a unfettered -4. And my preference from past installations is to install it at the turbo for the aforementioned reasons, if at all possible.

The Crown Package utilized a single DRAWTHROUGH SU and a Corvair E-Flow Turbo (un wastegated) on a stock exhaust manifold with a tubular steel adapter. Turbo Tom sold a Holley Draw Through setup using a Rajay and an external Wastegate. This could move a ZX through the 1/4 in 11's, and easily in the 13's at low boost levels. Ultimate on the carb turbos though were the HKS and Cartech blowthrough Triple Mikuini setups. Both made gobs of power (over 450HP+ when set up with the correct carbs and turbos in the HKS's case) Both mimicked the Maserati BiTurbo in function, sans modulator rings. Long Story Short: DON'T DO IT! Go EFI, and if you must use triple throttle bodies, then do it with EFI. Drivability nad boost transition during light throttle is FAR superior (nay, seamless!) with one EFI.... Don't get me started! Triple Mikuini Blow Through Turbo 1987-2003 Now Megasquirted! 1966 Corvair Corsa Turbo 1989-Present, working on Megasquirt Blowthrough T/B conversion! 1962 VW Microbus Single Holley Drawthrough (Turbo City Kit) 1981-82, Dual Blowthrough Dellortos with proper Modulator Rings 1982-87---sold for finances and replaced with dual N/A engine. Soon to be Megasquirted Centermount Blowthrough Turbo Again!

The restriction of oil flow to the bearing is seal related, true, but there are very complex forces working inside highspeed turbomachinery that manny people are unaware of... too much oil can cause a measured decrease in spool up time, excessive frothing in the pan (causing intermittent cavitation of the MAIN pump in some cases!), seal leakage, oil consumption, high oil temperatures blah blah blah... By restricting flow, you get better heat transfer from the oil that IS going in there, and returning far less volume of frothing oil to the sump. Those are the two biggest issues after seals leaking.

Dude, there is NO FIdle relay on a Z-Car! What I did was hook the Fuel Pump relay to power a Three Wire O2 sensor, and the Aux Air Regulator for fast idle operation just like the stock Dastun did (F. Idle. Fast Idle---get it?) This way, the items are only powered when the car is running, like it should be. I even alter stock cars to run like that. The F.Idle relay output is later used from the MS as the spark output on MSnS---on the diagram you posted, the yellow lead coming from the DB37 should go to the HEI module terminal "G" (marked "FIDLE" on the second schematic in the relay board, which is a direct pass-through). The tach lead pickup would be determined by what version board you show---you are showing a V3 MS unit, but the schematic is for a V2 MS unit---and I am not sure the tach pickup circuit is the same on both boards.

he he he, for instance, I can link you to a photo if a Toyota Truck that runs a 4-71 Detroit, turbocharged, mid engined, and goes over 150mph. He did no modifications to that Detroit, still 17:1 compression, but LOTS of boost, LOTS of cold icewater in his air-to-water intercooler, and HIGH gears. He does 0-152 in about 1.3 miles....on dirt. That's respectable! If he didn't stretch the frame 14 feet for stability on a minitruck, he could easily house his mill under a standard cap, and really screw with people's minds! LOL

A late note I have is that from the originally proposed sketches, Idea 1 is the closest to the Nissan Factory Underbelly Pan that was used on the Z432R's. The underbelly pan was used in conjunction with the G-Noses' lower apron (which went back to the lower radiator support, where the underbelly pan started) and went back to the rear of the transmission. It was complete with drainage / servicing holes for fluids. It was made of FRP, and is shown in the Fairlady Z parts catalog from 1972 if anyone is interested in what it looked like. That underbelly pan was what Nissan used when wind tunnel testing the G-Nose during development of the S130 body. With a slight Rake, The G-Nose and headlight covers, and that bellypan the Cd of the S30 was reduced from .465 to .38X...

Have to agree, the block threads are NOT NPT, they are BSP (1/8-27 BSP I believe) For the restrictor, you can also use braze in the base fitting, and simply drill it out. For the inverted flare portion, as Yasin did, drilling and then adapting to something you CAN use is the easiest option. Welding is nice, but a threaded solution would also be possible. I forgot where I saw it, but there was a BSP "T" Fitting available, that would allow you to do essentially the same thing Yasin did, and still screw the stock sender in the end of it---I think it was for sale at Pegasus Racing in New Berlin WI... Was a Male-Female-Female "T" configuration in BSP. They deal a lot with English Ford stuff there, so they have some strange BSP fittings available. The feed to the turbo would simply be a BSP to AN-4 (with restrictor added) which should be available almost annywhere---a Parker Store would be a good place to look. A Brass or Aluminum BSP to AN fitting makes it really easy to tap the bottom of the fitting, and screw in an older Rochester Carburettor Jet to use as a restrictor, and makes it easy to change later if you want more/less oil. The Rochester jets were a standard machine screw thread---1/4-20 I believe, and their sizing in simple: a 50 jet is .050"! Good Luck!

I'd skip reading magazines like SCC if I were you. The compression you are talking about does NOT utilize an intercooler, and they are injecting up to five gallons a minte on several stages of turbocharging compression until the last one where they do no inject any coolant in order to get enough heat to ignite the fuel when injected! The stock LD28 was available in Europe with a turbocharger, I'd look to getting a Euro Turbo Manifold (the turbo is the standard T3 with a .43 A/R turbine housing) this, along with the Euro Fuel pump assembly to allow for the increased boost will give you a diesel with the HP of a gas engine, but torque like you will not believe. For instance, the 2.7L Tubodiesel available in the 2000 Frontier Ute had 170 HP and 285 Torque, with a EuroCityCycle fuel economy rating of 35mpg (thereabouts, it was expressed in KM/L) My 3.3L Gas engine here in the USA only had 170HP, and not NEARLY that much torque. The newer 3.0L Turbodiesel with direct injection is even better! But I digress. The way to give low end (off boost) torque is with HIGH compression, to get high end horsepower, you get BOOST---intercooled for proper efficiencies. Intercooling is the key, if you intercool a Diesel, then you can leave the high compression as then the temperature will be brought up to autoignition temperature. If you LOWER the compression, then you HAVE to boost high to get heat into the air charge so the lower compression will bump the charge to autoignition temperature. Remember you can't preignite a diesel, because the fuel isn't in the chamber unitl it's SUPPOSED to be. Problem is with non-intercooled diesels, is that they will not have the smae power as one with an intercooler simply because of less dense air. You're a bit backwards on what you need to do to reach your goals---might want to read a bit more technically oriented magazines that go into why things are working the way they do, instead of a periodical that caters to a skim job on the technical end of it... Anyway, the Diesel is a different animal! A normal LD28 will return 40mpg in a Z, and with a turbo, the preformance can be startling---easily equalling that of a stock gas engine, if not surpassing it!

Wow, that is different! Then there are THREE versions of the Turbo Distributor, one for JDM, one for USA, and one for Eurospec! I guess this makes sense, the JDM and US Emissions laws are similar, so their engine controls would be similar. But the German and Euro Market L28Turbos (rated at 200HP) indeed have a simple pneumatically retarded distributor as I listed above. Learn something new every day I suppose, but now I am wondering where I got an obviously Euro Turbo Dissy in my collection, when I have it marked as "84 Skyline L20ET"? Damn, the intrigue continues. Thanks for those photos! The output from both should be similar---Nissan is very standardized within years as to what signals they wanted to incorporate. I O-Scoped the US model 81 CAS, and compared the Waveform to an 82/83 CAS unit, and they were identical traces---I would suspect if you find the right two wires, the hall effect shaping circuit in there will give a similar output to the ECU as any of the other Turbo CAS units. What you will be looking for the Megasquirt will be the signal from the individual pickup on the "bottom" of the Dizzy in the photos above. This will give you the six firing signals you need for the trigger. You will probably have to use the HEI module same as on the other units, but hookup is identical. You can test the hookup using a DVOM and watching the pulses coming out while turning it by hand fairly quickly. The two wires that give you the pulse when you wiggle one point of the reluctor past the single pickup will be the one you want. I might also say that the wiring color and wire position of the single picku will be the SAME as the 82/83 unit because it's the same on the 81, and they both use the same plug to interface with the stock ECCS system. The upper portion of the dizzy is unused---it is the leading trailing setup that is incorporate in the 81 CAS to interpolate 1 degree increments, and on the 82/83 unit as the megaslotted outer ring to give the one digree resolution. Good Luck, take a look at Mobys Stickies over at Megasquirt Forum here and between the two it shoudl go together smoothly.

What defines High Rev Diesel? Isn't the stock limit on the LD somewhere in the high 4000's? 4600 comes to mind. It will send a Z to about 112mph with stock gearing, so with a little gearing play that top speed could be improved upon, but given a diesel is a torque engine anyway, the boost will make getting to 112 pretty fast! IMO, the rev limit on the LD28 needn't be raised, it can all be accomplished through gearing, just like on large trucks.

I've got the manual for the TECII if that would help ya. I am in the process of booking dyno time to remap our 2L L20A for Bonneville from the L28 map that is in there now. Do you have the WINTEC program for readjustment? "State of the art, 1999" LOL

Guys guys guys! We are all trying to be helpful, but us boys in the US of A are just confusing the poor gent of Oz. The L20ET as well as Eurospec L28ET's did NOT have a special optical trigger or crank trigger unit like we got here with the ECCS system! The dude from Kiwiland is hitting on it, and basically the Non-US turbo cars had a standard style ZX distributor with the control module on the side, and a SIMPLE pneumatic retard/advance cannister on them. For guys with a simple Megasquirt setup, having one of those Euro Dizzies would be the hot, simple ticket for a quick install without having to screw with the timing maps. Anyway, Kiwilad has it correct, the turbo dizzy will actually retard a SIGNIFICANT degree when you pressurize the "advance pot" on the side of it. If you apply a vacuum, it will move one way to give you 7 degrees advance, and if you let that vacuum off, it will return to the "middle" of it's range, when you apply 7psi to the thing, it will move the OTHER direction about the same amount, for 7 degrees of retard. Aside from that, the weights and advance points are slightly different, but I have no information on that. A N/A dizzy will not move appreciably when you blow pressure into the pot, unless something is broken! Hope that clears it up for ya! Good Luck, Cheers!

The intake he is referring to is a transplant form a Nissan Sedan, not used in the Z-Series from the factory, but will fit no problem. It was used in Cedric and Gloria Saloons and Coupes. Correct, it had a plenum with runners that came "underneath" and curved around the outside of the plenum before opening to the plenum proper. Basically the inlet to the runner is on the fender side of the plenum, and not hte motor side! I transplanted one of these into a 1978 Fairlady Z, and was amazed by the down-low torque. Then again, it had the "two barrel" throttle body also, using a smaller primary body for about 3/4 of the throttle pedal throw, then a larger secondary body that opened over the last 1/4 of the pedal travel. You cruised up to around 3500 rpm on that little hole, nad had nice high vavuum numbers for economy, and got a suprising kick when stomping it compared to the first 3/4 throttle! It's a common intake overseas. I have photos on the laptop, but not on-line. There were two different "TWO BBL" Bodies, also, one for the L20A, and another for the larger L28, make sure you have the right one for the L28 if you want decent breathing!

I ran a JDM turbine housing, and could get full boost at 1500rpm, and the unit would surge badly at 21psi. But not at 20. The overspeed is one item, but that is only a matter of balance. The balance really isn't what kills them, the half thrust bearing it what kills them! The load you place on the compressor wheel (simply put, designed for 5 psi, now running 4X that) quadruples the bearing loads on a thrust bearing that is marginal in the first place. As the bearing WEARS (and it DOES WEAR) the axial movement of the impeller increases. On lift-throttle event where the rotor assembly makes a full available axial movement and SLIGHTLY kisses the housing, and that is the beginning of the end. What was in exquisite balance previously is now out of balance, nad starts the beating bearing road to failure. Industrial turbines have "startup rubs" all the time, and run forever because their bearings are overdesigned. But in an automotive turbocharger design practice is a little less.... So you have a half-thrust bearing instead of a 360 degree thrust bearing. And no matter where it goes first, turbine or compressor, once it kisses due to wear you are on the road to ruin.

I used a 60mm T/B from a 91 Sentra SR20. All you ned to do with that is remove the quadrant, and the outer spring, and bolt your stock linkage arm on. It comes with the POT style TPS. I don't know what the fascination withthe other unit is, other than it accomodates the stock early TPS for people screwing around with the Stock ECU. For a MS conversion, the Stanza body is EVERYWHERE and does not require rethreading, nor shortening. Look at my Cardomain Page, and you will see that throttle body. Plug n play, baby!