Michael

Asking a somewhat transparent question… how does the low-end and midrange torque of the E46 330 compare with the 350Z? I have a love-hate relationship with my E36 (1992 325is). I love the RWD and the overall dynamics of the chassis (well, at least at my level of driving “skillâ€) but I’m deeply frustrated with the lack of torque. My 1990 4-cylinder Honda Accord has more torque off the line, and that is a very embarrassing admission! A fellow at work recently bought a Porsche Cayman, base model (not “Sâ€). Though of course the market segment is rather different, soon after buying his Porsche at my request he test-drove a 350Z. His report was that compared to the Cayman, the Z felt more sluggish in moderate-speed corners, but was at least as fast in straightline acceleration.

We don’t need FEA for a back-of-the envelope analysis. The JTR-type brackets can be thought of as beams (roughly speaking), with the engine as a point load on one end of the beam. The moment at the root of the beam goes as the distance to the point-load squared; 5.5†vs. 3.5†cantilever --> ~ 2.5X more moment. Meanwhile, if you double the depth of the beam then the moment of inertia (strength) goes up by a factor of 8, but that’s not what we are doing here; here we are doubling the thickness of the beam, and that is a linear increase in strength. However, as Grumpy pointed out, 1/4" steel plate is already thick enough, since it is much stronger than the crossmember’s mounting pads. In my Z the engine has 6.25†setback (altered firewall). The engine-mounts go to footers welded to pads welded to the frame rails. This is almost atop where the tension/compression rods protrude, as johnc suggested. And the aforementioned pads spread the load to avoid stress concentrations.

Moving from urban (and urbane) California to small-town Middle America can be a traumatic experience. I moved from Los Angeles to Dayton, Ohio in 2000. It felt like political exile to Siberia! The shock was staggering, and I’m still working through the depression that the move induced. I travel to Reno annually for an aerospace engineering technical conference; in fact, just came back from there last week. While every town must surely have its strong points, after a decade of annual trips to Reno, it strikes me as dreary and benighted. Unlike small towns in the periphery of a large city, Reno is isolated, and must fend for itself. But it lacks the authenticity of a self-sustaining town, trying instead to be a tourist trap like a mini-Las Vegas. Oh, and the winters are almost as brutal as in the Midwest. Regarding formal education vs. personal initiative and ambition… clearly one size doesn’t fit all, so consider: if you prefer a structured environment where you can concentrate on your technical area of expertise, then “corporate slavery†is the way to go, and an embossed fancy piece of paper is how to get there. Big corporations - and especially the biggest corporation of all, the federal government - loves fancy pieces of paper. If on the contrary you prefer seat-of-the-pants improvisation, devoting years on formal schooling may not be productive. Small businesses seem to care more about targeted expertise, such as familiarity with the latest programming language. Who among us doesn’t crave the romance of entrepreneurship, or at least the laid back social environment and “get it done†focus of a small shop? Big bureaucracies dawdle and run in circles, while small companies are agile and reward competence and hard work. Well, maybe. But later in life many people realize that the security and insulation of working for a large institution also has its benefits. This means that we lie to ourselves regarding our tolerance for risk, eschewing compromise from hubris rather than from conviction. My recommendation is: stay in the Bay Area, and take classes part time at the local community college while keeping your present job and looking for a better one. After a year or two at the community college, you can decide whether to get a technical certificate (Microsoft network administration, automotive electronics, whatever) or to transfer to a 4-year college for a Bachelor’s degree.

When I moved to Ohio in the spring of 2000, my only vehicle was a stock 1978 280Z. I drove it through the winter of 2000-2001, which included perhaps a half dozen snowfalls, each of moderate intensity, and each followed by rather haphazard plowing. On level roads there were no problems if driving modestly. But on one occasion I decided to try a slide, taking a turn going downhill at an unplowed intersection one night. The result was a spin, with the driver's side rear wheel hitting hard against the curbside. The collision caused no body damage but bent the rear suspension, causing ridiculous toe and camber on the affected wheel. From then on, a tire would wear from moderately-used to dangling steel bands in about 3000 miles, maybe less. I retired the car in the summer of 2001, when the left-rear brakes seized. Moral: drive conservatively and you'll be OK.

Actually, this sounds like a clever swap. Relatively cheap, lightweight car with anemic stock engine, and moderately roomy engine compartment. The main trouble spot will probably be exhaust header clearance between the strut towers, and clearance between the driver's side header and the steering shaft. But fiscally... the LSx will be a lot larger than a Gen-1 SBC, because of economies of scale, supply and demand, etc. Sorry, couldn't resist!

Too late now, but why not, instead, 1. Buy a $3000 beater (like a mid-90’s Corolla) that would only need liability insurance. 2. Put $4000 in a Roth IRA for 2007 in the kid’s name, and add $5000 for 2008 3. And if he’s a good boy, contribute another $5000 when 2009 rolls around? That way you help him out financially, don’t throw good money after bad, and the investment is in an account that he can’t [easily] touch?

Z’s are even rarer in the Midwest! In the past 8 years, I have seen one of the road, one in a used car lot, one in a parking lot and three in a garage (those three belong(ed) to a HybridZ member). But on business trips to Los Angeles, I typically see at least one Z per trip. Z’s are old enough to be distinguishable from the modern imports, so that even diehard Midwestern muscle car fans tend to give them at least glancing appreciation. But V8Z’s are another matter entirely: they’re disdained by the domestic and the import crowds alike. But that, I suppose, was one reason what this site was started!

On the other hand, this new Vette will weigh about 200 lbs more than the Z06, will cost 2/3rds more, will have less engine displacement, will be more complex, and ups the Hp only by around 100 over the Z06. My hope is that with the Z06 no longer being top dog in the Corvette lineup, Z06 prices will ease a bit.

Driving Pete’s car with the 327 and Tremec was challenging for me. It was actually my first drive in a quality-built V8Z with a manual transmission. The clutch felt finicky, the shifting was troublesome and the overall feel of the experience made me nervous. But by personal admission I’m not a good drive and have little experience with powerful engines and the generally notching transmissions that high torque-capacity seems to accompany. So I almost stalled Pete’s car trying to ease it into his garage in 1st. On suburban streets, I would shift too soon, and probably ride the clutch too long during shifts. With more seat time in Pete’s car, I would have gotten more comfortable with the clutch and with handling the car off the line, but my general squeamishness about high-rpms would have made it difficult to take full advantage of Pete’s car, even with considerable experience. My big block Z - when it ran (engine still disassembled, hope to drive it again in the spring of 2008) was an entirely different animal. Engaging first gear was difficult - harder than in Pete’s car. But for whatever reason, aggressive upshifting could be done with some precision - just by shoving the shifter back (1st into 2nd , 3rd into 4th) or forward (2nd into 3rd, 4th into 5th). Often this was accompanied by crunching noise. More leisurely shifting, such as in traffic, was oddly enough MORE difficult than violent shifting on rural backroads. Clutch effort was similar to that in Pete’s car, but the clutch was more forgiving. The main difference was the torque: an aluminum-head roller-cam 454 in a 2600 lb car vs. a more high-strung 327 in a 2800 lb car and ~200lb more of passengers. Gear ratios were almost the same, except that that Pete’s car has a 3.70 differential and mine has a 3.54, and his has an overdrive 5th. Actually, if I were doing things all over again, I would give serious consideration to an automatic with overdrive, perhaps manually shifted. Being “in the right gear†just doesn’t have the same importance with such an excess of torque. Heel to toe and the other fancy stuff seems impossible with the sort of brutal manual transmission necessary to handle the torque, and probably isn’t necessary any but the most sophisticated application - which mine is not.

I used to have a 1990 Toyota Corolla with “16 valves†stamped on the rocker cover, but I’m pretty sure that it was SOHC.

Like all tools, CFD can be very useful in the right context, but otherwise becomes just another hammer. That context is a “tuned†setup where various configurations have been gridded and run through the code, with validation relative to experiment. Once such a setup is in place, it is straightforward and productive to make configuration changes (add spoilers, lower the ride height, block off the radiator grill) and so forth. The incremental effect of replacing air dam A with air dam B becomes believable. But until all that infrastructure is in place, all CFD answers will be clouded with doubt. The “ballpark†figure will probably be correct, but the increment between air dam A and air dam B will be smaller than the uncertainty in either of the answers. But as I’ve been mentioning elsewhere, car aerodynamics is actually harder than airplane aerodynamics. Much of the car aerodynamics business remains in the wind tunnels, while today perhaps the majority of airplane applied aerodynamics is done computationally. Computations are generally cheaper, so wherever the industry can get away with doing stuff on the computer, they will. There are many reasons for why the automotive world still largely relies on wind tunnels, but I think that the main reason is that numerical methods are so tough to “tune†to work for cars. So the bottom line is: CFD is not necessarily intractable for our Datsuns, but odds are that it will be easier, cheaper and more productive to stick with the wind tunnel. I still believe that we should consider option #3: testing scale models in a university wind tunnel. I don’t mean Franklin Mint 1:18 models, but 1:5 clay/wood models that we would custom-make ourselves. Here’s another thought: the Henry Ford Museum in Dearborn, Michigan has a beautiful display model of the 240Z, at around 1:5 scale. While that won’t work for a wind tunnel model, wouldn’t it be nice if we could make molds from that model?

This is something that I would love to one day do with my 1992 325is. Stock it had around 180 hp, and in present condition probably makes less. Off the line it’s slower than my 1990 Honda (2.2L 4-cylinder), and the Honda is in dire beater condition. In many regards it is a very satisfying car to drive - good handling, reasonable creature-comforts without lavish ostentation, pleasing aesthetics and compact external dimensions. In many regards it’s superior to present-generation coupes. It just lacks power. The engine bay is relatively roomy, as is the case for most L6-equipped cars. It’s just begging for a LS3 swap! But to me the complexity of such a swap would be overwhelming. It’s a 15 year old car, but when I open the hood, any enthusiasm to work on it becomes instantly drained. Recently I did manage to replace the thermostat - took several hours, amidst much cursing. The clutch throwout bearing gave out over the summer - I didn’t even consider doing the job myself. It seems that everything in the European-car aftermarket is a ripoff, but if I were to act on doing the BMW V8 swap, at this point I’d just pay a shop to do it.

On my first attempt playing with this software, it gave hp/torque curves very similar to Desktop Dyno’s predictions - except that it’s less optimistic than DD on low-end torque, and the torque curve doesn’t fall as steeply as DD predicts; DD really penalizes high-rpm torque rolloff for advancing the cam. For camshaft recommendations, the intake lobe that’s their #1 choice is almost identical with what I ended up at - lift is exactly the same, duration is 3 deg less; can’t exactly compare area under the curve due to insufficient information. On the exhaust side, their recommended lobe again has the exact same lift, but about 10 deg less duration. (disclaimer: being in a hurry, I picked head flow numbers from the supplied library, which was closed to what I have, but not “exactâ€). For the cam that I ended up buying, I intentionally picked higher exhaust duration as a crutch for poor E/I on the heads (Brodix Race-Rite) and a weak exhaust system. Also, I went with 112 lobe separation - as mentioned already in this thread, Comp has a fixation on 110. So, bottom line: the approximation is sound, given the sparse input deck and necessarily coarse assumptions. But if you already know what you’re doing (OK, sort-of ), all that this software will do for you is provide a warm-fuzzy.

My one experience (which is for a big block) is Brodix, from their Race-Rite series. Comparing what I have with anecdotal evidence on the others, I’d say that quality is above-average, but not exceptional. The CNC’d combustion chambers have a definite “staircase†pattern, the rocker studs protrude into the intake ports and the deck has ~1/4â€-deep marks from a 1/2" drill, evidently used to secure the heads when doing the CNCing. However, the casting quality is very good and there are no fitment problems. The stock exhaust port and spark plug locations are a definite plus. I went with Brodix because AFR simply refused to make oval-port BBC heads. Brodix flow numbers are great on the intake side (especially given their 271cc port volume), but mediocre on the exhaust side. This led me to a cam with strong exhaust bias - which is hopefully going to work out well.

Katz’s book is a good start, and his reference list is an excellent one-stop-shop intro to more specialized material. That said, his book has some drawbacks from the viewpoint of explaining the theory and from practical tips on what does and does not work. As a second reference I recommend: "Aerodynamics of Road Vehicles" by Wolf-Heinrich Hucho, Editor. It is published by SAE International. Knowing that blocking off the radiator grill area had such an effect in the first wind tunnel campaign, we can infer that front-end mods are a useful area for concentration; replace the stock hood with something more “swoopy†and with a smaller fishmouth, improve the airdam and seal the area underneath the car between the airdam’s lip and the steering crossmember. I believe that this will yield max bang for the buck. Smoothing the underbody, recessing the exhaust, adding diffusers etc. is hypothetically cool and is great for bench racing, but is impractical because there are too many variables and too much fabrication is required to get it “rightâ€. My own wish-list would be to explore front-end modifications that take advantage of the space freed up by V8 installations, lowered radiators, etc.

A lot of folks, including some very accomplished racers and mechanics, seem obsessed with the notion that a L6 is "naturally balanced" - that it has a sort of mechanical purity that no other configuration has attained. And the forced-induction crowd often prefers inline engines for what is probably a simpler exhaust system, and hence an easier turbo installation. Personally I applaud the trend away from L6 to V6 (for example, in Mercedes). Maybe someday the BMW 3-series will be V6, too.

The swap is easy if you know your way around cars, if you have the tools and a suitable environment to work, if you have the time to do the job, and if you stick to a reasonable plan. Otherwise the swap won't be easy. A '72 Z and a carbureted 350 V8 are about the easiest choice for a swap. In fact the biggest challenges may not be in the swap itself, but getting the engine to run right - the usual stuff in any hotrod project.

Slightly off topic, but I'm reminded of an episode of the British car show "Top Gear" from a couple of years ago, featuring a review of a special-edition (but still factory, at least in the UK) Evo with 400 hp. First, the Evo was driven all-out on a road-racing track, and posted a time comparable to a Lamborghini something or other. Next, the host drag-raced the Evo against an economy rental car with a ~90 hp 4-banger. Both cars started in their highest gear, at 50 mph - and both drivers floored the gas. The result was remarkable - the rental car actually pulled ahead! It walked away from the Evo, while the latter was hopelessly out of its power band, and unable to build boost.

V6, L6, V8, whatever.... what perturbs me is that this thing is supposed to weigh >3800 lbs in Japanese trip - perhaps even more for U.S. spec. That's about the same as a Shelby Mustang on the proposed 2009 (?) Camaro. How's that for progress/technology/innovation?

It seems that in the car hobby, as in most hobbies, there are two peaks of activity: folks aged <25, and >45. In between those pesky career and family obligations invariably detract from time, money, and motivation.

I went the exact opposite route from starting my own business - got an undergraduate engineering degree (aerospace), then got a government job and the gov't paid for my grad school degrees (also in aerospace) - piled higher and deeper. Now my job consists of a mix of in-house research, program management and administrative stuff. The job isn't bad, but the location is very contrary to my preference. And being a very narrow and deep specialist, relocation is not an option; you become married to your lab! From my experience, there is very little difference between school and the "real world". Nearly every day I open at least one of my old textbooks. A large part of my job is running experiments, taking notes, reading and reviewing technical literature, and writing papers. If I were to change jobs, the logical alternative would be academia.

Back during my graduate student days in the Los Angeles area in the late 1990’s, an acquaintance of mine had 3 or 4 Opel GT’s - all stored in a Caltech parking garage. Two were parts cars, but one was spotless. The rotating headlights and lack of rear hatch were rather quirky, but the exterior aesthetics were very attractive. I’ve heard of Opel GT’s as drag cars, with everything from 426 Hemis to turbo 4-cylinders. Personally I think that the best swap option would be a Mustang 5.0 V8, built mildly to around 250 hp. This would probably be the threshold at which chassis reinforcement or major suspension mods would not yet be necessary.

It seems strange to have a BBC vs. SBC debate on a Datsun site! That said, let’s clear up some misnomers… - all pushrod engine families are having problems these days wiping lobes on flat-tappet cams. There is anecdotal evidence that big blocks are more prone to this than small blocks. My single data point is a 1978 Mark IV BBC into which I installed a Comp 262 Xtreme (or whatever it was called) hydraulic flat-tappet cam, together with their matching springs - back in 2000. Wiped the cam after 20 miles, despite by-the-book break-in. Now I run a mechanical roller. - It is true that the BBC valvetrain is heavier than that of the SBC, but a matched set of lifters-cam-pushrods-valves-springs-retainers, set up with correct clearances and installed-height, will even the playing field. - If you do buy good aftermarket valvetrain parts, prices for SBC vs. BBC are not much different. The notable exception is heads: BBC heads are around $2000 assembled, while comparable SBC heads run $1000-$1200. - The BBC family has no equivalent to the LSx; a more proper BBC vs. SBC comparison would be Mark IV BBC vs. Gen I SBC. - 500 hp is about the break-even point, beyond which a BBC build becomes comparable in cost to a SBC build. Head north from that, and the BBC becomes cheaper. - There is no JTR-type kit for BBC installation in a S30 Z. Some people have however successfully used a very similar approach, while others have used firewall setback (me) and still others have gone the full tube chassis route (Ron Jones, Brad Barkley) - The BBC remains an engine for specialists, who grew up using them or who just prefer their layout over the LSx engines. As I’ve been saying for many years, the “best†engine to swap is the engine with which you personally happen to be most familiar. That may not be the most elegant, or most economical, or most advanced engine - but if that’s the engine with which you have the most experience, that is the best swap candidate for you.

Business savvy is a great trait to nurture and ultimately to use to get out of the proverbial rat race. Our society assigns a special prestige to business owners. And don’t forget the tax breaks; $300K/yr of business profit is taxed much more leniently than $300K of salary! But not all of us are risk takers, and many would be wiser to take stock of their strengths and weaknesses, and to remain employees. In science, engineering, finance, medicine etc. there are many worthwhile institutional employment opportunities whose remuneration potential rivals what you’d pay yourself as sole proprietor. I mean, if you’re a carpenter then almost certainly you would do better by owning a carpentry business than by working for one, but if you’re a physicist you may think twice before quitting your university job. That said, lots of guys on this board are natural do-it-yourselfers, who started out not knowing a crescent wrench from a tire iron, but who went on to craft gorgeous cars from rusted-out barnyard specials. I can’t imagine how you can make a living reselling parts on E-bay or running a mail-order business from your basement or running your own chassis fabrication shop, but some guys do precisely that, and very successfully. So maybe more people on this board should be exploring self-employment, especially before family responsibilities curb one’s risk tolerance. For myself, the plan is salaried employment and defined-benefit pension. I’ll explore the wild-side after I’m 50…. As for "live for today, because who knows what tomorrow might bring": I beg to differ! I'd rather live miserly and die wealthy, never enjoying a single cent of my net worth, than risk running out of money before I'm dead.

The “paint†and “interior†numbers are optimistic, but otherwise this reads like a reasonable cost estimate for a stock-ish swap, assuming that you already have a Z in decent condition, make no suspension mods and are content with a bolt-in “roll barâ€. Relaxing those assumptions and starting absolutely from scratch, the cost will conceivably double, or worse. The result becomes a decent-looking, decent-handling 2900 lb (if based on a 280Z) 300 hp $12K-$15K sports car, which takes a patient and moderately skilled fellow about 2 years to build. Compared to a late 90’s Z28 Camaro, it will be 600 lbs lighter, probably better-handling but slightly less reliable and much less comfortable. Still, a favorable comparison - provided that you do all of the work yourself. Farming out work to others, following dead-ends, suffering blown-up engines and other setbacks will however reverse the favorability of the comparison.