BRAAP

Just as Mario and Sidwell suggested. The firewall VIN is stamped into the firewall so that will be THE vehicle VIN. I don’t have one handy, but it he beginning of the Black Dragon (formerly Victoria British) catalog is break down of VIN numbers and the years of production for those VIN numbers. The dash and door tag can easily be replaced. Also a few things on the Dash (if the dash and instruments are original), can distinguish the exact 280 model. ’75 280Z had and Amp gauge, in 76 it is Volt gauge with charge light. In 77 the font style of the instruments changed from the older 240/260/early-280 font to a more modern thinner font. Then in ’78, the Speedo also had KPH in blue font, in side of the MPH. Firewall VIN stamp, above the brake booster on the firewall. ’75-’76 Door striker ’77-’78 Door striker ’75-’76 deep spare tire well and full size spare tire ’77-’78 false rear floor with shallow spare tire well/space saver tire ’75-’76 speedo, (note font style) ’77 speedo (Note font style) ’78 speedo (Note font style) ’75 AMP gauge (Note font style) ’77-’78 volt gauge (Note font style)

One of my favs..

What sort of “top speed” are you looking for? Making a trip to Bonneville of is the street car?

There is a 50/50 chance your P-90A has the hydraulic cam. Some P-90A heads still had mechanical lifters. Click ME to see a P-90A with mechanical cam Good luck, Paul

In post#42, there was mention of the difference in how the crank pins come out in a non twist forging in its 180 degree state vs a dedicated single plane crank. At some point between that post and this page was more discussion about that and if memory serves…. Ah heck, I don’t recall the specifics, I just recall we had discussed it a little bit.

Don’t feel bad and don’t get discouraged. Honest mistake, no biggee. Keep looking. Something is bound to turn up eventually.

Along these lines, years ago, I had thought about what it would take to get a twisted forged SBC crank, though before it was twisted, and then just machine the crank pins. … *** edit *** Ah ha… Found it. Back in Post #42 of this thread, was mention of the twisted vs non twisted forgings.. http://forums.hybridz.org/showpost.php?p=772054&postcount=42

So close , yet so far… Thanks for keeping your eye’s peeled for SBC single plane cranks, sorry to be the bearer of bad news, but that is not a single plane crank. It is a dual plane. Look closely at the crank throws, there is one every 90 degrees, instead of 180 degrees. Typical inexpensive forged cranks are forged in a single plane, then while still glowing hot, are twisted to form the dual plane. To forge a dual plane crank in the dual plane, require a more complex forge, hence the added cost, but that non twist forging is supposed to be superior in strength to its twisted brethren.

Nissan GT-R at 3800-3900# lbs! For any sports car, regardless, 3800 lbs is fat. On paper the Nissan GT-R’s performance and capabilities look stellar, the car is a very complex computerized machine. Its looks? Well that’s in the eye of the beholder. For some reason it is the 3800+ lb weight that keeps stabbing the back of my brain. My full size Luxo-barge, Infiniti Q-45, with half tank gas, no driver, weighed 3800 lbs! Anytime a “sports car” weighs the same as a flag ship luxury car, regardless of how sensuous it looks on the show room floor, it's a... Hmmm… so take a 90-96 Q-45, (can be had for under $5000 in excellent condition), rebuild the engine to withstand 20-25 lbs of turbo boost… Utilize the latest track proven Z-32 suspension components and mods... you with me?... (Q ship and Z-32 share front and rear suspension design), now around the track, the Nissan GT-R driver is feeling a little uncomfortable as he can’t seem to shake Grand-dad, maybe just a little, but Grand-dad is still in his mirror, (Grand-Dad is a term of endearment we have for the Q-ship due to its “boring”, “no-one-looks at it” sex appeal, not even the police give it a second a look.)

Mtcookson, How feasible do you think it would be to leave the intake manifold base on the VG30E and fab a new, short, upper plenum to accept the M-90? It should be much lower overall than the one pictured here, possibly only a couple inches taller than an N/A plenum overall maybe? Or build a water to air intercooler into that new upper manifold, would be little a taller, yet allow for more boost? What are your thoughts, any other ideas?

The “pressure” results from the centripetal force which is the result of the bearing clearances only allowing “so” much oil to escape, vs how much oil is being fed to the bearings from the pump AND from being flung away from the crank centerline out to the rod journals due to CENTRIFUGAL force! Centripetal is the inward force that resists the centrifugal OUTWARD force, Centripetal could also be the measurement of whatever is holding back the mass from the centrifugal force, i.e. pressure. Just as you described with the Moon, the Earths gravity is the centripetal force in that scenario holding the Moon in orbit, while the speed of the Moons orbit along with its mass is resisting the centripetal force, (dat dar be da centrifugal force), trying to fling the moon away from the Earth, in a straight line, yet the earths gravity isn’t allowing that. Same as in the oil galleys of the crankshaft. At that, this is car guy stuff, not quantum physics. We are all accurately understanding what is taking place on the same level, regardless of the exact terminology. Grumpys post stands and will remain. Feel free to take this up with your professor/s.

You sir should to go down to the quickie mart and buy a lottery ticket… How are you determining these to be LSD? If those are indeed truly LSD, then they were installed by someone else, and also being as the aftermarket supports LSD for the R-180, and the Suby also came with an LSD R-160, and the R-160, R-180 and R200 will fit, we have no idea what diff is in the car until we can see it for ourselves.

Oh my… 8 years… A huge thank you to SuperDan for THE worlds premier extreme performance Z car site.. We wont get into how much of that 8 years we actually spent in front of the screen pounding the keyboard…

Yeup! That about sums it up.. ... Thanks Jon.

Thanks for the Link Brad-man As Ron stated, the specs for the OE 240 and 280 cams are the same.NO OE cams that came to the states in a Z car had .433" “valve” lift. .390" and .413" are the common “valve” lifts for the OE L-6 camshafts. (don’t forget to subtract valve lash in your calculations when measuring the nose vs. base circle "before" you multiply the rocker ratio). If your measuring and calculating technique is accurate, then that is an after-market cam. At that, .433" doesn't make sense for an after-market cam, i.e. why would an cam grinder bother with mere .433" lift? In '77 the cam oiling for the L-6 switched over to internal. internal and external cam oiling is interchangeable. Just swap the cam towers. Internally oiled cam with internally oiled cam towers and vice versa. Do NOT mix cam towers from different heads, nor mix cam towers from their relative positions on the head. Stamp them 1-5, (or whatever system works for you), front to back and install them in the same order.

DD is a ’93 Z-32 Plan “B” is my ’90 Chev full size half ton 2wd, extra cab long bed, (farm truck)

Ahhh.. That could suck lots of time for sure. Thanks for sharing... Around 8 years ago I found one even more powerful at sucking the time out of ones day, week, month, even year.... Check it yo!!! Click ME for penultimate time sink game...

Six Shooter hit some very goods point in his last post regarding the Torque vs HP and how it comes to be, so a lot of what I'm saying here is just restating what he said. When comparing a similar HP bike engine to a car engine, yes the bike engine will be working harder in that car vs how hard it worked in the bike, (10 second bike vs a 15 second car with similar HP, so be sure the engines cooling system and lubrication system, is up to the task of working just as hard, for longer stints...). The bike engine when used in car would be lugging around a lot more weight now, but the cars performance shouldn’t suffer if the cars engine that the bike engine replaces produces similar HP and both are optimally geared, (keys words, optimally geared). Deeper over all gearing will be used with a bike engine to take advantage of the bikes RPM and deliver similar torque at the wheels, (the cars acceleration). Point being that comparing the HP and torque figures of high revving bike engine vs low revving car engine are relative, not as offset as the numbers themselves make it appear. For example, if the bike engine produces 200 HP @ 12,000 RPM and 100 ft lbs of torque @ 6000 RPM, it is the 200 HP you’ll be making use of, the gearing in the transmission/rear-end will take care of “torque at the wheels”. A transmission is merely a Torque multiplier/RPM divider, as well as the diff. Lets use an arbitrary L-6 for example, that produces 200 HP @ 6000 RPM and 200 ft lbs @ 3000 RPM compared to an arbitrary 200 HP @ 12,000 RPM, and 100 ft/lbs @ 6000 RPM bike engine. (these are general figures for the purpose of showing the relationship in how they accelerate an equivalent weight car and in are in no way ideal or what you will find in the real world, but the point still stands. There may be other forces at work such as drive train losses etc that will affect each a little differently, but those are beyond the scope of the point being made here.). If both of these engines were in identical cars and those cars weighed identical, they would post similar ¼ mile ET and MPH, i.e. accelerate similarly from a dead stop, even though the bike engine is down on torque, it is making up for the lack of torque with RPM. Lets break it down a little more. Both cars using identical 4 speeds transmissions, but the bike engine car is using a diff ratio of 7.08, the L-6 powered car is using diff ratio of 3.54, (half the ratio of the diff in the bike powered car). The Bike engine produces half the torque of the L-6, but spins twice as fast, so its diff ratio is twice as deep. (Keep I mind, this scenario is general just to set the idea and concept that a bikes lack of torque does not equate to lack of available acceleration when the gearing is optimized to take advantage of the bikes higher revving). In this scenario, both cars are shifting at the same vehicle speed, the tires are seeing the same torque at the ground as well as the same HP, (just as Six-Shooter eluded to, the tires are spinning at the same rate, yet the deeper diff ratio of the bike powered Z is effectively doubling the torque that passes through it to the tires vs the L-6 diff, i.e. torque multiplication through gearing. That is why 1st gear in our cars feels so darn quick when accelerating vs 4th gear. Torque multiplication). In summation, generally speaking, the relationship between HP and Torque is important and is not to be discounted, though keep in mind the ft/lbs maybe less peak, the RPMs are grater, thereby compensating/making up for that lack of ft/lbs. Just because a bike engine produces similar HP to a car engine, yet only half as much Torque, that does not mean when installed in a car that it wont pull/accelerate just as hard. The Bike engine revs more, so the gearing will be deeper, therefore delivering similar Torque to the wheels and accelerate the car similarly.

You know better than this. Whooping up on a triple carbed Z on the road means squat diddly regarding how good an induction system is at making power. This is simple guys, either back up your claims with a time slip or dyno charts, street racing accounts are not valid PERIOD! There is an L-6 powered street car with SU’s, N/A running documented 12.8’s at the strip. There are similar and faster triple carbed L-6’s as well, N/A. Lets see some dyno sheets and ¼ mile time slips, not just … “I beat up on car once…” Don't trash this thread with useless posts!!!

With my ’75 280, I ran dual pipes out the OE bumper holes. Dual 1 ¾” then dual 2” with the L-6, then dual 2 ½" with the V-8. I used angle cut chrome tips for all of them. For the 2 ½” exhaust, I had to open up the holes, mostly making the holes more circular vs the OE oval, was needed for adequate clearance. Also had to modify the fuel tank to get the passenger side pipe through, (looks like you already have that hurdle cleared). Personally, I think if the exhaust pipes must be a visually seen item, that through the valence gives it a more finished exotic custom appearance. Here was mine with the dual 2" while it was L-6 powered.

DETONATION!!! The L-series is especially quite sensitive to boost “issues”. Your engine is Detonating itself to death. Broken piston skirts, three blown head gaskets, DING DING DIGN!! Detonation!!! Your crank was NOT hitting your pistons. The assembler would have seen/felt that happening during assembly if that were the case. If the combination of parts, (pistons, cylinder head for a pump gas friendly compression ratio), and the tune, (ignition timing, fueling requirement using an aftermarket EMS or an OE Turbo EMS). What parts are you running, i.e., dished or flat top pistons? What cylinder head, i.e. casting number on the passenger side? Also, what engine management system are you using? Was the person/s tuning your engine knowledgeable and more importantly experienced in tuning boosted engines? On the first blown head gasket, the red flag of detonation was waving. The second blown head gasket, was your DEAD giveaway as to the problem, DETONATION and action to rectify the detonation should have been implemented by this point(actually the first time the head gasket blew, should’ve been the clue that something is wrong and something should be changed before it happened again). The detonation is taking place on one side of the combustion chamber which is forcing your pistons to rock violently which slaps the piston skirts against the cylinder wall, breaking the bottom of the skirts off the pistons. With detonation this severe, Good chance your rings and ring lands are also collapsed/busted! Your rod bearings may even show signs of being squished as well, depending on the severity of the detonation and how long it has been going on, (apparently several times). other issues such as cracked crankshaft etc could arise... In short, your entire short block needs to be completely torn down, new pistons, maybe new bearings, etc. Searching the archives here on HybridZ, make sure your new pistons and head combination are compatible with each other under boost. Also, search the archives here for appropriate tuning parameters for builds similar to yours. Always start out your boost levels, fuel requirements, and timing advance on the conservative side. Here are a few pics borrowed from other threads, Turbo L-'6s that experienced detonation. This is the region of the piston skirts that bust from detonation. Blown out head gasket from detonation. Busted pistons from detonation. Notice the busted ring lands and pistons skirts...

EXACTLY! The R-180, when used up front in an AWD Z car, should be able handle pretty much anything thrown at it torque wise, even with slicks up front! In a milder street tire shod AWD Z application, I would even consider the R-160 up front. This is really a topic for another thread. Pretty cool huh? It would be nice if we could talk him into writing up a page or six, detailing first hand, his cars build up and performance in our projects section...

VG30E TB is smaller then 60mm, just a little larger than the OE L-28 TB. At any rate, a throttle body swap alone, even to 60mm or larger especially on stock or even mild L-28 will net you nothing you would ever notice. The stock intake manifold runners are the biggest hindrance to air flow as well as the stock exhaust system. There are SEVERAL other mods to perform that will net noticeable gains in performance before the OE throttle body becomes a restriction and should be considered at hindrance to performance. Here is great thread on larger throttle bodies; Click me for Large throttle body discussion For gains in performance, Start by advancing your ignition timing. OE is 10-12 degrees BTDC at idle. Bump that up to 15-17 at idle. There are many other easy mods that will deliver noticeable gains in performance, which can be found through the HybridZ search engine. Good luck, Paul