Michael

Harsh crowd here! Having spent 20+ years tinkering with my Datsun, having it be my garage companion through several human relationships and countless too-human failures and foibles, I'm sentimentally attached to the machine. But it's not what I really want. It's my companion, yes - but not my dream. And this thread asked about dreams. The dream would be a truly iconic racing-car, that redefines the possibility of what's possible in vehicle-engineering. Short of that, the mini-dream would still be a foray and achievement far beyond anything that I've been able to do, or might ever likely be able to do. Thus, again, the term "dream". As to reacquainting ourselves with hardnosed realism, the "dream" is to merely sort out and to render reliable what I've already tried to do. The engine that I have currently installed has "potential" for some 500 hp (it is after all 461 cubic inches, with some top-shelf parts is semi-semblance of good order), though I doubt that it actually produces half as much. The brakes... occasionally work. The car is squirrelly, ill-tempered, rough, more of a white-knuckle facsimile of amusement than anything serious on the road. I dream of fixing that someday.

* Full chromoly tube chassis (custom designed, verified with extensive finite-elements modeling) * Unequal A-arm suspension on all four corners, based on some blend between Miata and 5th/6th-gen Corvette (with suitable design and testing) * Carbon-fiber body panels affixed to tube chassis, after proper wind-tunnel development * LS7 (Chevy 4th-gen SBC) engine, twin turbo * TBD gearbox * Ford 9" differential and center-section, with suitable half-shafts and inboard brakes * Lexan windshield etc. * VIN from 1970 Datsun Z welded into firewall In other words, the only Datsun part of the car would be registration as a Datsun. It wouldn't even attempt to resemble at Datsun in its external lines, let alone internal components. Why not? Because there are too many compromises in building a "dream car" from the initial canvas. It's taken me 20+ years to figure that out.

Miata.net itself admits that its search-function is subpar. Recommendation from the more venerable members there, is to search for a topic via Google, thereby finding the right Miata.net thread. For purposes of troubleshooting or getting advice on repairs or minor upgrades, it's fantastic. For things like V8 swaps into Miatas, the utility of the site is more suggestive than explicit. Then there's miataturbo.net. Rather sophomoric and dismissive attitude by veterans towards newbies, but the intent is noble: they're trying to keep the site technical and useful for rigorous instruction, rather than water-cooler blather. Much of their content leans toward electronics and tuning... probably of use to the turbo and fuel-injection-oriented people on HybridZ. And yes, that Manta is spectacular!

This looks like a novelty. Based on the physical size and the gear ratios, it looks to be a direct competitor to the G-Force revision of the venerable T5 (https://www.gforcetransmissions.com/tran_gt-5.asp)... prices are similar. The G-Force version appears to have slightly higher torque/hp capacity. Let is know what you think of it!

And now, 19. Canadian drinking age, eh?

It’s interesting that you mention Miata.net. I’ve been active on that site, for a decade or so, but mostly from the viewpoint of stock or lightly modified Miatas. Miatas are lovely cars to drive, but noxiously difficult for V8 conversions, requiring very substantial re-engineering for even a stock LS1 (or similar) V8. The S30 Z requires so much refurbishment and sorting-out just to be livable on a daily basis, but the cavernous engine-bay is unrivaled as recipient for a large engine. Miata.net doesn’t have the level of FAQ as does HybridZ. There is no equivalent to the wind tunnel campaign that was done for the S30 back in 2007. There are no legendary members like JohnC, whose posts have come to be pillars of received wisdom. And there’s surfeit of dumb “newbie” posts about generic and trivial things. But Miata.net remains lively because of persons to whom it appeals: middle-aged men who remember when the NA Miata came out in 1989, who couldn’t afford it then, or for whom family/career/etc. interfered, and who now have the time and the garage-space to tinker. Without making a swipe at our younger brethren, it seems to me that for whatever reason, Z’s tend to appeal to people who are less established in life, less-experienced, who have more eagerness and dreams than wherewithal or practice. So, the questions tend to be both ambitious and naïve… which is irritating to the veterans. If somebody asks why his 1991 Miata is running roughly, it’s a quick deduction that the catalytic converter has clogged, suffocating the engine; or the plug wires, notorious for going bad, have indeed gone bad. If somebody asks what’s the best way to swap a Hellcat V8 into a 1971 Datsun, and will the rear-end be strong enough, well, that’s a much more irritating question, is it not? Also, it seems that for whatever reason, the originals/regulars on HybridZ have gone silent. Some have passed away. But others I’m sure are not only very much alive, but still own their Datsuns. What happened? What happened for example to “Katman”, to Terry Oxondale, Pete Paraska, Mike Kelly, Denny411 and so forth? On Miata.net, we have numerous people with 20K or 30K posts, who have owned a dozen Miatas over the years, who have been buying and selling, driving and storing, modifying and preserving them for nearly 30 years. Why has the same trend not persisted with HybridZ? Also, there are modern questions on perennial stalwart topics. For example: “Suppose that I’m happy with stock brake-power, with maybe performance pads and SS lines. But I want lighter brakes, for less unsprung mass. And I don’t want to deal with drum brakes. I don’t want to rifle through junk-yards. I don’t need or want 13” rotors or 6-piston calipers. I called Wilwood and Arizona Z-car, and that’s all that they had. What else can I do, now, in 2019”. Or: “So, you guys tested a bunch of Datsuns in a wind tunnel in North Carolina with no moving ground-belt, no boundary layer sucker and some high blockage. My university has a high quality wind tunnel with a moving belt and capacity to spin the wheels using embedded electric motors. With have a 6-component internal force balance and a particle image velocimetry system for getting time-resolved 3D measurements of the flowfield behind the rear hatch. What should I be thinking in terms of a test matrix?” Or: “My engine makes 650 ft-lbs of torque. I want a manual transmission with overdrive, but don’t want to deal with the weight of a T56. I need a blowproof bellhousing because I sectioned my firewall for 10” of setback beyond the JTR method, and my race-sanctioning body wont certify my car unless they see that SFI sticker. I called G-Force, and they told me that at my power levels, it’s either a T56 or bust. And everyone at my track insists that I install a Powerglide… but I want a proper manual transmission, with overdrive. What should I do?”

Don't do this. Have patience, and spend more money (if necessary, vastly more money!) on a car with fewer problems. Otherwise you'll spend 5 years doing rust-repairs, 5 more years doing structural reinforcement, and 5 more years nursing your wounds after you realize in year 11 that new rust has already formed where you had replaced the old. Alternatively - and it sorely pains me to say this - look for a less rare, less rust-prone vehicle of comparable low weight... such as a Mazda Miata.

Facebook is one of those newfangled enterprises that's completely passed me by. That forum traffic is falling because of the alternative of Facebook would be surprising... but only because I'm ignorant of Facebook. A related problem occurred at our local BMW enthusiast meetup, "Ohio Bimmers". Because it's more local, it's more conducive to semi-regular meeting in person. I would host "wrenching sessions" at my house, with some 5-10 participants in a typical gathering. Well, these were a common occurrence 10 years ago. They've since petered out. The culprit is demographics. Most of the participants were younger fellows, typically freshly out of college, age 23-26. In the ensuing years, they've done the Big 3: gotten married, had kids, and bought a house. The Big 3 are enormous drains on one's time, one's spare energy and one's capacity to engage in hobbies, be it modifying Datsuns or playing chess or going mountain-climbing, Perhaps in another decade or two, once the kids are grown and in college, the former participants will return. Meanwhile, some of the founding members of this site were around age 35 in the year 2000. Today they're in their mid-late 50s... seemingly the ideal time to reengage in hobbies. And yet, most are absent. Have they moved on to other cars? Have they burned out? Some, I know, went through divorces... then recovered and remarried. Others... who knows?

And that's golden advice right there! The JTR book itself exhorts readers to be sparing and parsimonious in their ambitions. Do a swap, not a "restomod"! Is the recipient-Z in good shape? If not, the swap will be unsuccessful, or at least a protracted effort. If yes, then there's a 25-year-old recipe for getting it done. The only thing that 's not thoroughly documented (still!) is the clutch hydraulics for the T5... throwout bearing, flywheel and pressure-plate and so forth. That's the only part that involves a modicum of improvisation. But here's the thing... you do the swap. You get it hooked up, bolted up, connected, buttoned up. Congratulations! Now you have a hot-rod. That hot rod requires tuning! Can you tune the ignition, the carburetor, and so forth? Do you understand port vacuum and manifold vacuum, proper spark advance, and so forth? That is the difference between a strongly-running car, and a turd. That is something with which you'll need to wrestle, whether or not you swapped the engine into a 240Z, or bought a Chevelle or Nova or whatnot with that engine native. And that's the art/science that's been waning and vitiating over the years.

Mpg depends largely on engine management: carburetor vs. fuel injection, camshaft profile and so forth. 20 mpg should be readily attainable even with a more aggressive engine build. However, truly high efficiency, in the sense of a modern sports car, will be hard to attain - even with the 240Z's weight advantages. The reason is lousy drag coefficient... the bane of good highway mileage. To answer your questions: 1. Do as little as possible, at least initially! Complete the swap, get the engine running and the car sorted out. Engine mods can come later. 2. This is entirely subjective and situational. So enterprising drag-racers are pushing 500-700 hp (or more!) without molesting the "stock" look. 3. Never, ever ever install a non-overdrive transmission in a "daily driver" Z! Your application is screaming for a T5. 4. Initially, do nothing. Between your relatively weak stock 350 and the stock wheels/tires, the R180 differential in your 240Z should be adequate. Later you can swap in the much stronger R200. Search the "drivetrain FAQ" for model years/varieties from which to swap the R200. The #1 discriminator between failure and success, is the condition of the Z that's about to become the swap candidate. Rust? Overall condition? How is the suspension? The brakes? Do things work in general? Are bits falling off? Rubber? Plastic? Doors close properly? Dents/body damage? Electrical systems? You're about to do an engine swap. Don't also make it a restoration. The #2 discriminator is falling into the "while I'm at it" malaise. Do as little as possible! Laziness is always its own reward, but sometimes it's also this best route to quick and definitive success. This is one such instance. Be strategically lazy!

Perusing the data from that 2007 wind tunnel test, I'm baffled by the results for the Pantera hatch. Intuition suggests that flow is already separated near the front lip of the stock hatch, and then continues as a set of oscillated separated rollers. This is because the stock hatch angle was poorly chosen. It’s too steep (pressure gradient too high) for attached flow, yet less efficient than a blunt (high angle), abrupt rear element… such as for example the back of a VW Rabbit. The rationale for Pantera hatch is to get up on attached flow, instead taking the pressure-drag penalty on the rear windscreen, but hopefully getting flow reattachment further downstream over the hatch. It is possible that this latter phenomenon wasn’t achieved in the wind tunnel test. I’m not criticizing the wind tunnel test, but am pointing out that (1) the result was counterintuitive, (2) the drag increase from the Pantera hatch was still small, compared to the unrelated issue of what’s done at the radiator/nose/airdam, and (3) design-variations on the Pantera hatch are still possible, which may actually reduce drag, instead of increasing it. By my reckoning, the benefit of a Pantera-style hatch isn’t a “hatch” at all, but a fixed lid over the trunk-area, merging into a fixed rear glass (or plexiglass). The benefit is (1) save weight, and (2) isolate the cabin from the fuel-cell and battery (assuming a trunk-mounted battery). If there is aerodynamic benefit, then that’s a bonus, rather than a main objective.

These are both factors. The intentional push to make this site more of an archive and repository for knowledge, than a discussion-venue, has cast something of a pall on freewheeling banter. Too much clutter of course obscures the useful information; the idea behind this site has considerable merit. But it's not without adverse consequences. I'm finding that so many methods that were revolutionary in 2000, are now mundane, or even obsolete. Suppliers have changed. Technology has moved on. As our cars age and become rarer, the emphasis shifts from engine-swaps to rust-abatement and restoration. "Parts cars" have all but disappeared. Instead of swapping damaged or inferior parts, the emphasis now is on improving what's at hand. Soon it will be time to post another Happy Birthday message to this site; it's about to turn 19! I miss the bygone years of intense activity, even if indeed most ideas have already been covered, and new discussion is not always warranted.

I have two data points, for both of which the evidence is scant and only qualitative: a 1972 240Z, and a 1978 280Z. I partially gutted the doors of my 280Z, removing the longitudinal crossmember and a good portion of the inner-wall sheet metal. I placed the detritus from both doors in a cardboard box, and weighed the box. It was, if memory serves, 10-12 pounds. The 240Z door shell-material may be lighter gauge, but the architectural difference between the two sets of doors is worth only 5-6 pounds per door... if that. My original 240 ended up getting sawz-alled (is that a verb?). I was shocked by the thinness of the sheet metal... but wasn't sufficiently engaged to measure it with calipers. Before cutting the tub apart, I used vice-grips to pry apart, peal back and cut chunks of sheet metal. Later, I did the same for the front bumper supports on my 280. The qualitative difference in sheet metal gauge was... significant. My casual hypothesis is that the preponderance of the weight difference in going from 1970 to 1978 is in the gauge of the sheet-metal, rather than the engineering of the tub (bumper supports, radiator supports, A-pillars, subframe "connectors", etc.). To Grannyknot's point...since your 280 tub is on the rotisserie, would it be possible to weigh it? Bathroom scales are notoriously inaccurate, but at least it's something... they have typically a 300 lb limit. Perhaps one scale could be put at each end of the rotisserie? Or would that damage the scales? My stripped 1978 280Z - with a fairly elaborate roll cage, a 454 big block Chevy and a Doug Nash 5-speed, weighed 2720 lbs, on 4 Longacre scales. This was with, at the time, cast-iron heads, most stock sheet-metal intact, stock hood etc. Since then, I've replace heads/water pump/etc. with aluminum, and have removed quite a bit of metal, undercoating and other bits. Hood is now fiberglass (homebrew design).

There was an observation made on this forum some years ago, of how many members had "graduated" from the S30 Datsun to... a Porsche! The rationale was that they wanted something quieter, more luxurious, more elegant, and yet... something quick, responsive, well-sorted, rust-free and suitable for an elegant night-on-the-town. A late 1990s - early 2000s base-model 911 can be found for around $20K. Automatics will be cheaper than manuals, and yes, they have power-steering. The 240/260/280Z doesn't lend itself to luxury. It's hard to simultaneously achieve good handling and a compliant ride. It's hard to quiet-down the noise (wind, engine, tires). It's expensive to equip the interior in luxurious finishes. And it's quite a prodigious challenge to introduce the various modern electronics that are now associated with luxury. By buying a car that's 25-30 years younger, you get all of that... plus substantially more engineering-development, and a dollop of prestige (if that matters). The advantage of the Z is its rawness and simplicity. To each his own, of course... but replacing that rawness and simplicity, with refinement and complexity, sounds... challenging.

That's an eminently fair point; we're all better served by comparing the existing options with some newfangled innovation. Novelty by itself is no advantage, and is perhaps a disadvantage, being untested and probably more costly. But we should observe: this is (now) 2019. Options that were current and available in 2005 or 2012 aren't necessarily still so. Our cars are becoming rare. Junkyard parts no longer fit. Suppliers have moved on to other markets. In some cases, venerable vendors have quite literally passed away. Now more than ever, we have to improvise... especially since 4-lug wheels from any manufacturer in any size - and at ANY price - are becoming a rarity. What was 10 or 20 years ago a vanity project - big brakes, big wheels, whatever - is now becoming a necessity. Some of still have semi-complete Z-cars that have been hibernating in garages for quite literally decades. When will they emerge? And when they do, what about bushings, ball joints, brake calipers, wheel bearings and the like? Here's wishing the best to Invincibleextremes, and here's looking forward to more progress!

It's good to see this thread be reinvigorated... now running for over a decade! And yet - has anyone, over these intervening years, actually weighed a bare S30 tub (with all bolt-on stuff removed, all glass and rubber and plastic removed, etc.)? Has there been comparison between the 240Z tub and the various iterations of the 280Z? This remains, I think, the burning question. When this site first started, there was some flexibility in finding a 240Z as a starting-point, with the 280Z being an also-ran, a consolation or a shortcut, when the lighter and older vehicle couldn't be located. Today, all S30s are rare. None in any reasonable condition are offered inexpensively on Craigslist. We have to modify and preserve whatever example we happen to have in our possession, even if it's the 77-78 heavier model. Still, it would be nice to know, what weight-penalty we're paying, in going form 1970 to 1978, in terms of things that are not bolt-on.

Welcome indeed! When this site first started (in a few weeks it will have been 19 years!), there was much debate about "optimal" engine longitudinal placement. The main strategy for higher setback ran into conflict between the Chevy distributor and the stock Datsun hood latch. So, the latch would get relocated. In Techie's photos, the stock hood latch appears to be intact. It would help to take a closer photo, standing at the side of the car. Also take a photo of the engine-mounts. Are they long and cantilevered off of the steering crossmember? More engine setback is generally a good thing, but cutting the firewall is an adventurous exercise that often leads to having to gut the interior, rendering the car, ahem, "specialized". Most crucial after picking up a vehicle with an engine swap, is sorting out maintenance issues. How is the compression? Are the valves in adjustment? Is the ignition timing correct? It's remarkable how large can be the performance-difference between an engine that's in good tune, and one that's lacking. By this I mean simple things, like spark plugs or carburetor settings. An engine with well-flowing aftermarket heads, big cam, port-matching everywhere, free exhaust, high compression and so forth... maybe more sluggish that the most prosaic economy-engine from a taxicab, if the latter is well-tuned, and the former is not.

Congratulations on a successful resolution! It is indeed frustrating, how one might spend years on remediating rust, building a roll cage, inserting new frame rails, building an engine, etc., only to suffer deep disappointment because of some minor but insidious problem with the tuning (spark and/or fuel). But this happens often. Even if we can't diagnose the problem, and only solve it by swapping parts, well, at least the problem has been solved. Given your stack of receipts, perhaps you can do some sleuthing on the provenance of this engine... its parameters and properties. From that, it would be possible to select the "ideal" intake manifold and carb. And then maybe the final step would be tuning on a dyno.

Welcome! There are actually people around, who have been working on their V8 swap for 30 years. I've only been working on mine for around 20... plenty more experience to acquire. Surprisingly, nobody has yet ventured with the gruff admonition, to buy and read the "JTR manual". It glosses over the electrical details specific to the LT1, but is otherwise relevant, especially for engine mounting and interface with the transmission. By way of advice, I suggest first establishing a sound condition for the car itself: rust abatement/mitigation, brakes, suspension, that sort of thing. Swaps often fail not because of the swap itself, but because the installation of a different engine is part of an overall restoration project. It's so much easier when with the stock-engine the vehicle is already in good functional condition... especially if you have no reason for any aggressive chassis reinforcement or re-engineering (new frame rails, setting the firewall back, installation of roll cage, etc.). Good luck!

1-8-4-3-6-5-7-2 (GM firing order)... In your case, every other cylinder is non-firing? Such systematic failure is peculiar. HEI module? Is there a spare distributor, to replace the current one (the complete thing)?

The Muncie M20 was a "wide ratio" (for the times!) 4-speed. First gear is around 2.56, and fourth is of course 1.0.... not the best choice for a Z. Unfortunately there has been little progress in V8-suited manual transmissions over the past 20 years. This is understandable, as the Gen-1 small block and Mark-IV big block have been obsolete for 20 years. Several aftermarket vendors modify the venerable T5, or its peers (Tremec etc.). At 350 hp, one supposes that a fairly conventional T5 would suit. Mine is an older build, with. Doug Nash 5-speed (not overdrive!), but then again, the engine is not 350 hp. If I were doing it all over again, I would probably go with a G-Force variant of a T5. As Miles noted, the JTR book remains useful as summary of the OEM options. There may be reason to improve on it, as it were, using a blow proof bellhousing and a hydraulic throwout bearing.

The inevitable question is whether the effort in doing something ambitious (research, sourcing components, fabrication, testing and adjusting) is justified by the eventual benefits. My personal feeling is that for those who have the skills and resources to do this successfully, the question no longer needs to be asked. For the rest of us, it's too easy to get seduced by impressive theoretical options, that end up only causing frustration and dejection. That said, my preference would be to start with some kind of suspension modeling software. The more sophisticated ones are doubtless expensive, but there should be a basic one available as freeware. A swap that used at one time to be popular, or at least occasionally encountered, was the front suspension from the C5 Corvette.

The Mark-IV big block 454 is not to be confused with the LSX bored/stroked out to 454. The latter will fit anywhere that a Gen III-IV small-block will fit. The former is going to be challenging in a 300ZX. In the above post, the first photo is of a Mark-IV big block, while the second is the LSX. An fellow named Grumpyvette for some number of years posted expert advice on the care and feeding of the big-block 454, achieving both impressive performance-numbers and reliability. Doing this requires both an intuition for how parts go together, and as goes without saying, for acquiring said parts. Begin with the casting numbers on the heads and block. Are these a candidate for refurbishment, or ought one to ditch them, in favor of new (or at least alternative) parts? Writing today, in the summer of 2018, it is hard to justify a Mark-IV big block, unless one is particularly fond of them, has the parts and equipment to support them, and has a particular hankering for such a novel swap. I did this swap (with copious help) in an S30. That project included setting the firewall back 6". The big block will fit even without a firewall setback, and at least 2-3 people on this forum have built big-block S30s with stock firewall. Opinions on weight-distribution are of course their own matter. In a 300ZX, one supposes that the fit will be considerably less accommodating. If one is truly keen on doing this, one could aggressively cut metal and secure an eventual fit. Is it worth it? Again, very much a matter of opinion.

This site began (now over 18 years ago!) as an antidote to “purism”. Purism is a zealous affection for one particular brand or model, to the exclusion of all others, where one regards said brand as being inviolable, and any introduction of alternative components is “impure”. In particular, in the late 1990s, the V8 swap was first becoming systematized, and this site was built as a home for persons interested in such a swap, without facing taunts and vitriol of detractors. Later, we realized that it’s all too easy to become clannish and insular about the V8 swap itself, and so, all sorts of variants came to be welcomed. Technology and tastes moved on. Today, perusal of sub-forums immediately shows that the most popular thing is the turbo, quite often on a straight-6, whether from the original S30, another Datsun/Nissan, or an entirely different brand. Mechanics aren’t known for being philosophers, but to the extent that there is a prevailing philosophy, I’d summarize it as being an easy-going minimalism and openness to alternatives. The easy-going part, means that there’s no stark loyalty to any brand, year, national-origin or technology. If it works, use it. The minimalism means that the best approach is the simplest. Why add complexity for complexity’s sake, let alone, for mere appearances? The openness combines the aforementioned two. If upon completing a swap, there comes to be a demonstrably better way of doing things, the old gets yanked, and the new attempted; unless of course one grows tired of too much tinkering, and has the maturity to accept things as they are. Some of the most venerable members on this Forum have died. Others have lost interest, faded away, or just gone silent. I miss them, and I miss those heady early days, when seemingly by the hour there were new, insightful, stimulating posts – the repository of knowledge growing. Forums themselves have changed. Now there’s you-tube and facebook… online guides and quicky updates. Who has time anymore, to craft lengthy and detailed essays? My own car has now been in various stages of incompletion and completion, for some 20 years. I’ve often lost motivation, and honestly, haven’t had much of it over the past couple of years. But this stasis and somnolence are not permanent. I look forward to renewed garage-sessions… and maybe even a recrudescence of spirited posting on this forum.

Well, isn't it time now to be celebrating HybridZ's 18th birthday? It's now old enough to vote, to be drafted, to be criminally charged as an adult. It's not old enough to order its own parts, using its own credit card, with its own legally-valid signature. How will it function with its newfound maturity? On a more serious note - there must, there absolutely MUST be a HybridZ member somewhere out there, who wasn't yet born, when this site was started! Pray tell, who are you?