Pyro

I think I need to clarify what I wrote earlier. I bought my 6 puck clutch from Nippon Power and they sell Spec, ACT, Center Force, and RPS clutches. I didn't buy the ACT clutch. I did buy the SPEC clutch (just the clutch, no Pressure plate, for 150.00) which was a stage three, 4 or 6 puck (your choice), ceramic, with sprung hub. The stage 4 and 5 are solid hubs which they claim to give quicker engagements (stage 5 has iron pucks). They also say that 6 puck clutches or more streetable then 4 puck clutches.

A sprung clutch has those springs that go around the hub (like the stock unit). Street clutches will have springs to slow down the clutch engagment just a little. Most "pure racing" clutches will have a solid hub (no springs) which will make it even harder to drive on the street.

I use a spec 240mm, sprung hub, 6 puck ceramic clutch with a stock nissan 2+2 pressure plate so the feel of the pedal is the same as stock but the clutch is very sticky. It shutters more when cold and on slow take offs and in reverse. If a quick release is used then there is no problem with shuttering but the shuttering is a pain sometimes when driving "normal". A change in clutch operation will be needed to prevent shuttering. However, it holds the power from my turbo very well. Next time, I think I will try the kevlar clutch instead of the ceramic. But in any case, get the 240mm clutch as use the 2+2 presuure plate. The street clutch for the 2+2 (240mm) holds the same amount of torque the racing 225mm clutch holds.

It sounds more and more like the flapper in the waste gate. The flapper closes off the exhaust port in the turbo and makes the exhaust spin the turbine. If the flapper is gone then the exhaust will not spin up the turbine. So, if this is the problem then any external and wiring on the outside of the turbo will not do anything. I think you should remove the down pipe then remove the waste gate assembly and have a look. But first check if all your rubber hoses on the turbo outout are in good shape. Boost can also be lost at those connections.

You are at the limit of Z drive train. If you want to go faster without changing parts every 2 or 3 passes then you need to to sometime major. I have never broken a U-joint but my outer stub axles and diff pins have broken many times. I'm in the same boat as you, I need to change something big. My car has run 1.5 60 foots, 6.9@110 1/8 miles, and 10.7@135 1/4 miles. And I'm also spraying N20 on top of a 350 with a 5 spd trans and MT slicks. But I'm breaking parts and don't feel the car is safe anymore. Here is an idea for your N20 system. Buy a 1 gallon fuel cell and mount it in the engine compartment (drivers side by the radiator). Then get a small fuel pump to supply the fuel enrichment to the N20 system. This way you can run racing fuel in the 1 gallon tank. 1 gallon of fuel will last longer than a 10 lb bottle of N20. And your Holley will get a little help from the other pump. One way to limit drive train stress is to reduce the "shock" when coming off the line. I use a brake line lock to hold the car in place at the starting line and let the clutch out just a little before dumping the clutch. This technique takes up the slop in the gears, U-joints, and splines before the "take off" and reduces the hammer effect when the clutch is dropped at 5000 rpms. You could also do this with an automatic trans. As for me.....I have decided to go 4 link with ford 9 inch with a 3.08 gear, th400 with a 2500 stall, and IC'ed turbos on an efi 350. A year or two project!!!

Sounds like a bad flapper. Stuck open or fell off. You could also check the if the intake blades spin easily by pulling the intake tube off the turbo and spinning the blades manually (with the car off). You should pull off the down pipe and wastegate and make sure the exhaust blades are still there. And check the flapper while you are at it. Turbo boost is pure mechanical. Nothing electronic will stop it from boosting unless you have a bad electonic boost controller. And stock 280zx turbo's don't have electronic boost controller.

I have used them on the street without any problems. I painted both sides of the gasket with silver paint right before installing them. If you use the 0.015" thick head gasket you will reduce the head combustion chamber by 5 cc as compared to a regular 0.040" thick gasket, which is a good amount. How big is your cam? Where is the intake centerline installed at? More cam advance will increase cranking compression (earlier intake valve closing). As rpms increase so will the cylinder pressure when using a big cam (cylinder filling aided by rpm). Or you should use a cam that is more "intense". Quicker valve lifts and closings will increase cranking pressures while retaining the same duration at 0.050" lift. Go solid cam! I think you are running about 10.3:1 cr with your current set up assuming 355 cid, 8cc head gasket (0.040"), piston in the bore 0.020", and 2 cc valve reliefs in the pistons. If you changed to a 0.015" gasket (3cc) then your compression would rise to 10.7 cr. It sounds like you are using a 300 duration cam with soft ramps.

Oh! sorrry about that. LOL That's good! You already have a LSD. Have you tried any suspension tricks to increase weight transfer to the rear tires? Like.... removing front sway bar. installing soft springs and struts up front. installing hard springs and struts in the rear. It is hard to get both drag strip traction and good handling unless you have a 4 wheel drive or rear engine car. Another thing is, old rubber generally has bad traction. I don't know how old your current tires are but as tires age, the rubber loses traction. So maybe a fresh set of rubber will help. If you plan to go to the track more than 4 or 5 times this year then maybe you should get a set of slicks and another set of wheels. The difference between drag slicks and regular tires is huge at the track. I'm not sure but I feel my Z actually pulls the front tires off the ground just a little when using slicks.

N0, but the MT ET streets are street legal. They are built the same as slicks but have 5 or 6 very little groves cut into the rubber for what they call a "tread". But they drive like slicks on the road. The side walls are so weak, it makes to rear end of the car wonder around (good for straight line traction only). And if it rains the end rear will feel like driving on ice. Not very pleasant. I had slicks on my V8 Z but I trailered the car to the track and didn't drive it on the street with slicks. I have also used the MT sportman tires and they work pretty well at the track but not nearly as well as slicks. However, street driving was pretty normal and tread wear was acceptable. IMHO, I think you should get some regular radials and spend some money on a LSD. Or buy an extra set of rims and some slicks for the track events. Preicison Gear sells a LSD center carrier for R200 diffs for 605.00 which would be about the cost of 2 slicks and 2 extra rims. I recent installed a LSD carrier in my 1/2 ton 70 chevy pickup with a 454 engine and the LSD really helped out traction. Maybe you should consider getting and 3.90 diff from the junk yard and installing a new LSD carrier. The 3.90 will help low end power and the LSD will help traction. And, I bet your are tired of making single black lines all over the streets.

I didn't like the BFG drag radials at all. They didn't stick well (compared to slicks) and were expensive and wore out VERY VERY quickly. They were gone after a few smokey burnouts! I guess they would had lasted longer if I didn't heat them up before launching the car. On the other hand, a set of MT drag slicks lasted me 80 trips downs the drag strip and that included a smokey line-lock burnout before each run. But they require another set of rims to make switching from one set of tires to the other an easy swap. Mickey Thomson now has their own drag radial (not ET street drag tire) which was tested in this month issue of Hotrod or Chevy High Performance (i forgot which one). This brand new drag radial made better 60 foots in a few cases as compared to the MT drag slicks. However, I bet they will wear out quickly just like the BFG's.

Your launch will depend on which GM trans you are using and which Z diff gear under the car. 700R's have a very low first gear (3.08) and will give a 3.54 gear a 10.9:1 overall first gear ratio and a 12.0:1 overall first gear ratio if you are using a 3.90 diff gear. A 10:1 overall first gear makes a nice "hole shot" car. A th350 trans has a 2.50 first gear which will produce a 8.85:1 or a 9.75:1 overall first gear when using a 3.54 or 3.90 diff gear. You didn't mension which trans or gear your are using but I would guess you are using a th350 trans with a 3.54 diff gear, since you are wanting more "take off" power. The cam you are changing to should help low end torque. Furthermore, a small shot of N20 will also help you get off the line.

I rotated the turbo output nossel downwards and ran an output tube (2" OD) under the oil pan then turned the pipe up behind the alternator then out of the engine compartment on the passenger side of the the radiator. Then I relocated the AFM to the front of the radiator (extended the wires) and ran the intake tube (2.5") and tube from the cool side of the IC (2.5") into the engine compartment on the drivers side of the radiator. I posted the photo of this setup in the photo album between 6 and 9 months ago (I think). It looks good and is easy to work on. The car ran 13.7 @ 106 mph in the 1/4 mile with a slipping clutch, 10 to 12 psi of boost, 5 spd, stock T3, spearco IC, custom 2.5" down pipe, 2.5" exhaust, r200 3.90, stock 76 efi, and 80 psi of fuel pressure from the FMU. On the dyno it made 235hp but was very lean (stock NA injectors are maxed out). Boost comes on very fast and as low as 2000 rpm. There is a perfect area for the IC tube to run under the oil pan in a first gen Z. The IC tube is higher than the lowest part of the oil pan.

I forgot to give the cure for piston slap. Bore the engine and install new pistons. Make sure the machine shop knows what they are doing (quality shop). The shop should not bore the block until they measure the "new" pistons you are going to use. The use of torque plates during the bore out process will also make a big difference in engine "build quality". A backyard hone job and new rings on old pistons is the most common cause of piston slap. That is why forged pistons are loud when the engine is first started. More "cold" clearance is required for forged pistons because they expand more than cast pistons when they get hot. So when the forged pistons are cold, they rock in the hole which causes the skirts to slap the cylinder bores.

Yes, you are right. The turbo ecu controls the timing. I didn't see you were using the turbo ecu in your list when I first read it. So you may not have any control over that. I'm don't know what the factory ecu does with the ignition timing curve (retard, advance, and knock sensor). I hope it can handle a cr of 8.8:1 and 12 psi. My bubby's car dentonates like crazy if more than 18 degrees TOTAL ignition timing is used. At 30 degrees of total timing, it sounded like shaking a big coffee can with 20 or 30 marbles inside. In my and my bubby's case, we are using the stock 77 and 76 distributors so we can turn adjust the initial and total advance. But that is all, no knock sensors and just rpm dependent advance (very primative compared to computer controlled ignition). Sorry, I can't help with your ecu transplant. But good luck!!

Nice setup! However, 8.8:1 cr on a datsun turbo will be hard to tune out detonation. A friend of mine is trying that now on his 77 280 and found out 18 degrees total ignition timing under boost is all his engine will take at 6 psi, stock T3, no IC, 93 octane. We ending up welding the dist advance solid and hooked up the distributor vacuum advance to BOTH the manifold and to the ported vacuum (viva Y-connector). This gives a lot of timing off boost then redards it when the boost comes on. So, he is running around on 28 degrees (18 initial + 10 vacuum) timing under full vacuum or under no vacuum situations then drops to 18 degrees under positive manifold pressure. Not the best way to do it but it works. An after market ignition timing controller or an aftermarket efi system will come in handy to tune out dentonation. He is using an FMU to add more fuel under boost. I'm doing the same thing on my 76 Z, except I'm using the stock turbo compression (7.4:1). I 'm running a stock T3 at 12 psi, spearco IC, 20 degrees inital timing and 28 total (mechanical advance only) with no detonation.

Piston slap sounds more like a diesel engine sound and gets quieter when the engine warms up. It is caused by a loose fitting piston. Short piston skirts can make the problem worst. A ticking sound is normally an old lifter, or low oil pressure, in need of a rockerarm adjustment, worn cam, or exhaust leak. and normally gets louder as the engine warms up.

You should keep your head selection under 200cc. 170 to 180cc would be better for a street driven 327. And you should get the 64cc combustion chamber to maintain your compression. The AFR head is one of the best heads out there but cost a little more. Iron eagle heads and World Product Sportsman heads are a good deal and are about the same. Trickflows are nice but I think they require longer push rods and need washers under the head bolts. In general, aluminum heads run better at higher compression ratios and will make even less power compared to a similar flowing iron head at lower compression ratios (less than 9.5). Finally, most aftermarket cylinder heads require longer head bolts. I think you will also make more power with a more modern camshaft. The 350hp GM cam is pretty much a dog. It has very slow ramps and not much lift. It bleeds off cylinder pressure which kills power. Get an extreme energy Comp Cam or something like that.

(14.7 + boost pressure)/14.7 = "turbo muliplier"

I think the side view picture is used as general decription and it doesn't really show the shape of the header. The header did fit very close to the block (just like a block hugger) then it continued to a full length. Now I wish I tried them on my car before installing them on the 34'. Maybe a call to sanderson will clear that up. Prior to my 34 experience, I bought a full length Hooker header made for V8 conversions in Z cars. But that header didn't fit very well because the header wasn't designed for the "set back" position or shatter shields. I had to do some cutting and bending to get it to work. I did try those corvette headers first and they didn't even come close (as mentioned above). In the end, I wish I had just made a custom header because it took a lot of tweeking on the Hooker header to get it to fit.

Check out these headers from sanderson headers (SandersonHeaders.com) Angled plug head http://sandersonheaders.com/pagesbypartnum/c32ho.htm Straight plug head http://sandersonheaders.com/pagesbypartnum/c32.htm They are just like block hugger headers then turn into full length headers. This design is made for old street rods with big engines in small compartments. I installed a set in a 1934 chevy with a small block. I'm pretty sure they would also fit in a V8 datsun since they have the block hugger design. And I know block huggers fit easily.

That is strange. Chevy balancers should have a single line cut all the way across the side of the circle. There should be nothing on the pulley. If the heads are off then you can use a dial indicator to find TDC. Use a hole punch to mark TDC on the balancer at the 0 on the timing mark. If the head is on then you can use a screw in "stop" the goes inside the spark plug hole. Rotate the engine manually (gently) until the piston hits the stop then mark the balancer. Then rotate the engine in the opposite direction until the engine stops again and again mark the balancer. TDC on the balancer is centered between marks.

I would guess it would make a lot. But as long as the rest of the engine is setup right (intake, carb, ignition, compression, and exhaust) I'm running a 242 duration cam (comp cam 292H), full length headers, dual 2.5 inch exhaust, performer rpm, 11:1 cr, 200cc dart iron eagle heads, holley 750, msd 6AL, slicks, R200 3.90, and a GM T5 5spd. And my 240 can run 120 mph in the 1/4 mile without N20 and on pump gas. This means, I'm making about 384 hp at the wheels since my car weighs 2855 with me in it. The heads you are talking about would most likely make another 20hp over my iron eagle heads. When I use the N20, I can hit 134 mph in the 1/4 and 110 mph in the 1/8 mile (10.7 and 6.9 seconds). But diffs and stub axles require frequent replacement under N20 conditions. Bummer..

215cc heads on a 350 are good for high hp and high rpm (good drag racing head). You will lose some low end torque and throttle response using 215cc heads (not so good for the street). A 383 would make better use of a head that big. Or a 11:1 cr 350 with a 250 degree cam (@0.050) and a shot of N20. However, 600.00 is a good price. But it all depends are what you are looking for; drag racing only, street/strip, street only??? Those heads will most like require longer head bolts, head bolt washers, and longer push rods (+0.160"). I would use at least 10:1 cr with an aluminum head on the 350. Titanium valves don't last as long as stainless valves (good for racing, bad for the street). FYI, 200cc dart iron eagle heads (straight plug, 64cc chambers) cost 1000.00 new from Summit and would make a better street/strip head.

I see...... There is nothing wrong with a two bolt block. Mine is a two bolt and my V8 Z is running 10's. I think the performer rpm intake would be better and I don't like edelbrock carbs. I threw two in the trash a few years ago. The Holley 3310 (750 vacuum secondary) carb is much better than the edelbrock. Unless the edelbrock carb you are talking about is the edelbrock Q-jet series. The edelbrock performer series suck because they are made of the wrong material (aluminum) which cause them to heat soak (gas boilers) and the accelerator pump system sticks after a few months (bad design). That is why I threw them away, vapor locking and sticky throttle. You should match the engine compression to the cam you what to use. Here are some general guidelines: 8:1 to 9:1 use 190 to 210 degree cam (at 0.050" lift) 9:1 to 10:1 use 210 to 224 degree cam 10:1 to 11:1 use 224 to 242 degree cam 11:1 to 12:1 use 242 to 260 degree cam You should be able to change out pistons and/or use a thinner head gasket to get the compression you need since you are going to rebuild the engine. I would use the hooker block hugger headers. They work much better than stock manifolds. However, block huggers don't work as well as full length headers. But, block huggers install very easily in a V8 Z. Use the hookers (pn 2100) because they use 3/8" thick flanges.

If I were you and IMHO, I would drop the engine in stock. There is sooooo much more to do in a V8 conversion than the engine. The engine is the simplest part. A cam swap is only a one day job. Plus if you use the old cam, you don't need to do the painfull cam break in procedure right at the time you are just trying to get the engine to run in a conversion project. So just inspect the parts and reuse all you can and get the conversion completed before hot-rodding the engine. There is a lot more to go (trans, drive shaft, exhaust, fuel system, gages, throttle linkage, trans linkage, clutches or cooling lines, mounts, radiators, fans, and wiring to name a few.