This documentation contains various information on the V8 conversion as well as ramblings and thoughts.  Don't expect this document to make any sense.  It may also have a lot of errors in it, so if in doubt ask me about it.

When I get time I will start to fill in documentation on the L28ET turbo 240z conversion.

Table of Contents for V8 240z Conversion

Table of Contents for Turbo 240z Conversion

BODY

    I will be putting on the California Z fender kit, without the whale tail. I am not sure what I am doing for air dam. The Cali kit interferes with all of the air-dams I have seen, so this is TBD. I will be putting on a fiberglass cowl induction hood.  I have purchased some repair body parts including rocker panels and door skins. I’ll have to see how good my welding skill get before I try the door-skins. I will do the rockers once the floorpans, sub-frame connectors, and roll cage are installed.  Had to change plans because of the rust in the rocker area.  I will do the floor pan and sub-frame first, but will not attach the floor pan to the inner rocker, then I will replace the inner and outer rocker panels.  I will use 1x3 tubing for the inner rocker and this will tie into the sub-frame and roll cage at the front and back of the rocker panels.  I will probably have to tack weld some support bracing so that the car will not warp when the rocker panels are removed.  Tubing should run the length of the inner rocker and extend thru the front floor so it can connect to the subframe in front.  Also it will extend thru the back floor to do the same thing, thus forming a box with the rocker panel and the subframe.  The roll cage will then mount to the front and back outer corners of this box.  
    Fix the rust around the windshield and door jams.  Have a new windshield installed.

BRAKES/WHEELS

    It looks like Weld Draglites will be the wheel of choice for the car. I like the look of the wheel and they have offerings in 15” size up to 10” wide using the 4x4.5” bolt pattern, which works for the 240z. If I can fit a wider tire than 10” in the rear of the car using the California Z fenders, then I will have to go with a 5 lug upgrade in the rear. This will allow me to use a wider Weld Draglite wheel than 10”. According to TomaHawkZ I may be able to fit 12” wide tires with coilovers and the Cali Z fenders. Also, if I do a 5 lug upgrade I will want to do the disc brake upgrade at the same time. In order to determine all of this, I have to put coilovers on the car first so I can gain the most inside clearance for the tires. Then I will have to fit up the California Z fenders and see what I have. When the Cali fenders are on the car, the fender well will be cut out so that the original fender lip does not interfere with the tires.
    To do the 5 lug upgrade or disc brake upgrade, check out Mike(scca) for parts. There are also other methods and parts available.
    According to my info I want to use a 75 to 78 brake booster with a 79 to 81 master cylinder.  Also, replace all brake lines.

    In order to stiffen the chassis and do rust repair I am replacing the engine compartment frame rails, floorpans with zedd floors, adding subframe connectors and new frame rails under the floors, putting in an 8pt roll cage from S&W, and replacing the rocker panels. During replacement of the engine rails I will be build new compression rod mounting boxes that are heavier.  I have had thoughts lately about putting in jegs full tube chassis.  I may go this route.
    When installing the roll cage check clearance with side bars to the door arm rests.  May want to remove door arm rests to allow sidebars to shift outward for more seating clearance.  Also, may want to add a piece of 18awg steel under the car in the areas where the plates mount up to the floor board for stiffening.  It looks like Corbeau Clubman seats will provide enough clearance for the rol bar.  Tim240z is using these seats with the S&W roll coge.  The Forza seats are a little wider.  I will probably fabricate my own mounting brackets for the seats.  The roll cage main hoop wants to mount into the seat belt cups.  Use the 6"x6" plates at the tranny tunnel and up front on the floorpans.  Also for the rear tube mounts, put them near the strut bar, not too far back in the car becasue this will interfer with the gas tank.  May have to get fuel cell dimensions or order the cell to complete the back bars of the roll cage.  Make sure that the cross bar behind the seats is high enough so that the harness straps go straight back from shoulders to mount, otherwise if the straps go down in back before they mount they can cause spinal compression in a crash.

    I want to use the 24x19 griffin radiator for cooling. I think there are two versions of this, one has wider cooling tubes. I think the larger is 1.25” cooling tubes. I want to use the largest I can get. A two speed Ford Taurus fan will be used with this radiator. Use approximately an 1989 to 1995 fan. Look for three wires to signify 2 speed. The second speed should only be used if the car is heating up too high.

    I will be using the R200 LSD, which comes from 87 and a half to 89 300ZX turbo cars. The 88 SE300ZX pearl white car had a viscous LSD. I got inner stub axles from a 280Z so that I can try using the u-jointed halfshafts. These usually break with too much torque, use Brute Force u-joints Checker part number 1-0029BF for $14 each. The options then are to upgrade to CV jointed halfshafts. I was able to get a flange that goes from chevy u-joint 1310 to the 300ZX flange. I think it was part number 2-2-1819, I’ll have to doublecheck. This part is obsolete now from Spicer. I will have a local diff shop build a driveshaft for the car. In order to use the 300ZX pinion flange I have to modify the original 240z front differential mount. I will be using the Ron Tyler type front diff mount. This goes over the front of the diff using a chevy tranny rubber mount and eliminates the issues of diff nose rising under acceleration.
    I will be installing an A833 4 speed transmission that has 4th gear overdrive. The ratios are very similar to a 700R4 tranny, they are (3.09-1st 1.67-2nd 1.1-3rd  .73-4th/OD). Overdrive gives a theoretical top speed of 155mph with 3.7 diff and 15 inch tires.  It is a new process tranny. It has an aluminum case and only weighs 80lbs which is good. Can handle boat loads of torque. Its downfalls are the gear ratios and the fact that it is rarer than the dodo bird. I found one so I am going to use it until it breaks. It has a unique bellhousing bolt pattern which means there are no scattershields made for it. It was a dodge tranny used in muscle cars, but GM used it mainly in there Diesel engine pickups from 82 to 86. It was an option on gas engine trucks. The best way to locate one is to tell junkyards you are looking for a replacement for 82 GMC diesel 4 speed, made by new process. I will use a hydraulic throwout bearing with this. Mcleod makes these and it looks like you can get the master cylinder with it. Then I will just have to mount the master cylinder. This will avoid mechanical clutch linkage and avoid slave cylinder mounting.
    Driveline phasing:  use a magnetic angle finder from Harbor Freight to simplify these measurements for phasing.

    Use a mini starter and use a remote solenoid. Possibly relocate the battery to the rear of the car.  Also install a Honda S2000 push button for the starter.

    Be sure to use a 7” or smaller harmonic balancer. If you mill the block deck be sure to re-visit quench. Quench should be around .045 for best chamber burn, more than .060 quench causes detonation. Like to keep DCR somewhere between 7.5 and 9. 9 requiring 92 octane gas. Watch out with high lift cams to use rocker arms with long slots. Check valve to piston clearance by not putting a head gasket and only snugging a few bolts. Use the micrometer with a light valve spring or use the clay on piston method. The micrometer method may not reveal how close the outside edge of the valve runs in comparison to the edge of the valve reliefs in the piston. Clearance should be a minimum of .100 using iron rods.
    DCR turns out good using the 282 duration (hydraulic) cams. Starts getting low with 290 (hydraulic) cams. If I can run a thin head gasket like .020 and a piston with small valve reliefs like 4cc. This will help. KB FT pistons have 6cc valve relief. It doesn’t look like you want to run a dome or pop up piston because it hurts the fast burn chamber efficiency. Use hypereutectic pistons.  This is also using Trick Flow 23 degree heads with 64cc combustion chamber.  I also want to get a Weiand Team G intake either part number 7530 or 7531.  The 7531 has higher rise.  Or get a Victor Jr. edelbrock intake part number 2975 or 2999.  I will be topping this off with a 750 Holley double pumper with mechanical secondaries.  For ignition I will use MSD either 6A or 6AL.  I still have to decide what type of distributor and plug wires to buy.  Want to use a perma cool remote oil filter mount.  Also use a crane cams vacuum canister to help with brake vacuum.
    Will want to run with a Weiand aluminum water pump.  All of the following engine combos based on trick flow 23 degree heads.  However, AFR 190cc heads are the best and improve torque curves signifigantly.  They are more expsensive so it is a money call when I get ready to build.
    One cam choice is the Competition Xtreme Energy Mechanical Flat Tappet XS282S-10.  This Has 244/252 duration @.050 and .520/.540 lift.  Desktop Dyno shows 350lb/ft torque at 2000rpm and 450lb/ft torque at 5000rpm.  With max horsepower of 470hp at 6000rpm.  This looks like a really good build, with good quench, good DCR(maybe too mild because of being solid, lose lift and duration to lash(lash is only .012 on xtreme solid cams vs .030 on old technology solid cams)), flat top pistons with swirl combustion chambers.  As a rule of thumb they say to figure 8 degree less duration with solid cams, but is this rule based on lash settings of .030?
    A hydraulic cam choice if I decide solid is not worth the gain is the magnum 280H.  This gives a torque curve making 350lb/ft at 2K and 430lb/ft at 5K.  This of course is easier to use being hydraulic.  That missing 20lb/ft of torque on the top end eventually costs 50hp, but the cam should pull almost as hard up to 5K which is what really matters to me for a street car.
    My current thinking on camshafts is to first try the 272TL-6 oval track cam which shows the best torque curve between 2k and 5K.  Then if I don't like the idle and low end properties of it, switch over to the 280H magnum hydraulic.  272TL-6 shows best DCR and torque curve, but is a 106 LSA cam so idle may not be good.  However, it is a small solid cam so I have been told that idle may be as good as the 280H hydraulic cam.  More to follow.  272TL-6 shows 370lb/ft at 2K and 450lb/ft at 5K making 445hp peak.  20lb/ft of torque over the entire range versus the 280H cam.

    After reading Vizard's camshaft book I now believe that the isky 280H Megacam is the best for the application, if I can keep the exhaust free flowing.  This cam is similar to the comp 280H but has 108 LSA for better mid and top range performance.  The solid cams really fell apart after reading the book.

    I also bought the power series book on EFI systems.  After doing the 280zx turbo swap into the 73 z car I fell in love with electronic fuel injection.  I will use Megasquirt as the fuel controller.  This is a batch fire controller that will run 2 banks for the V8.  Lucas injectors for Mustangs are pretty cheap running about $40 for 42lb/hr.

    Use Hooker block hugger headers part number 2100.  I am not sure if i will run dual exhaust yet, but it looks that way.

    When replacing the fuel lines try to run ½” aluminum. Replace stock fuel tank with plastic or aluminum fuel cell. Use an electric fuel pump because the mechanical interferes with engine mounts.  The use of fuel injection requires a high pressure pump, baffles in the fuel cell, fuel pulsation dampers, fuel rails, pressure regulators, etc.

    For the interior I need to get a dashboard cover. I want to put in two corbeau Forza type seats and 4 point harnesses. I would also like to install autometer gauges and a Honda S2000 push button for starting the car.

    There will be several mods to the suspension. One will be coilovers. Mike scca sells coil over kits. Get 225lb front springs and 250lb rear springs. I have seen mention of toikico struts, but don’t know anything about them. I think I only have to weld a perch onto the strut tube for coilovers unless I want to lower the car, then I would have to section the struts.  Will probably want stiffer swaybars.  I will need to replace all of the bushings in the suspension.

    When doing the small block Chevy conversion you gain around 125lbs if I recall from the JTR manual.  Helping to offset this weight will be:  Aluminum radiator, aluminum heads, aluminum water pump, mini starter, aluminum intake manifold.
    The roll cage adds around 80lbs.  The new engine frame and sub frame connectors may add around 50lbs.  However racing seats save 24lbs for the pair.  Weld draglite wheels should save some weight, not sure how much.  Also the Fiberglass front fenders will save some weight.  The rear fiberglass fenders add weight because they are bond on types.  Also save with fiberglass cowl induction hood. Scottie says cowl induction hood weighs 21lbs and original weighs 37lbs.
    The original radiator weighed 16lbs.  Not sure what the Griffin 24x19 weighs, but it should save some weight.    
    I think the new fuel cell will save weight.  The old fuel tank and all hoses and evap crap weighed 28lbs.  Not sure what to so with the spare tire yet, because I may put the fuel cell where it use to be.
    The conversion to R200 LSD also adds weight.  The original R180 plus mustache bar and driveshaft weighed 80lbs.  The new R200 diff weighs 80lbs by itself.  The mustache bar weighs 8lbs.  So this upgrade will add 8lbs + new driveshaft weight.
    The original 4 speed tranny and bellhousing weighed 80lbs.  The new A833 4 speed and bellhousing weighs 80lbs.  I wil only gain weight on the tranny swap if the clutch/pressure plate/flywheel weigh more than the original parts.

Gains:

~300lbs gained in total

Savings:

~140lbs saved not including wheels, fenders, fuel cell

curb weight 2355lbs

Conversion Weight ~2500lbs

Other interesting weights I have found:

TURBO 240z COOLING

Turbo cooling is not as tough as V8 cooling IMO. I installed 280zxt hood vents to let hot air out from under the hood. I will also install heat shielding around the brake master cylinder. I removed the injector fan since I live in a cooler state. I am using the normal plastic clutch fan.

I replaced the R180 diff with an R200 diff. I plan to put the R200 LSD diff in the car. I has a custom driveshaft made for the borg warner T-5 tranny. I am using u-jointed halfshafts right now.

The basic wiring into the 240z is as follows. You need to get a Haynes manual for '79 to '83 280ZX. This is the one with the red cover. Look on page 252, this is the wiring diagram. You will see 3 plugs labeled "1,2,3" with circles around the numbers. This is at the lower left-hand side of the page.

The wires are as follows:

Plug 1= BR 12v power source. Positive

G 12v power source. Positive

Plug 2=Y start signal (+)
GL ground for inhibitor switch
YW speed sensor (not necessary)
Y A/C signal (+)
YW coil (-) (must use ignitor)
B fuel pump ground if using modulator

Plug 3=LR fuel pump relay
G ignition .signal (+) for air regulator
W not used
Y not used
BW ignition signal (+)

More to follow on 240sx throttle body upgrade, injectors, turbo selection, manual boost control, removing emissions, etc, etc.

I built my own 2.5" mandrel bent downpipe to replace the stock restrictive unit. I am also building my own 3" mandrel bent exhaust from the downpipe back with a dynomax bullet racing muffler.

The fuel system definitely needs upgraded for the L28ET engine. First you need a high pressure electric pump. I bought the autozone stock replacement to start with. You also need a larger return line to the fuel tank. It is also a good idea to add a sump and baffles to the stock tank.