Michael

Comparing a relatively stock American V8 with a moderately-built L28T or other small-displacement turbo engine, the main difference comes down to how much you value low-end torque. If low-rpm torque is not important, go with the turbo – it’s an easier swap. If the low-end torque is important (and for me it’s the meaning of life, existence and the universe) then it would be difficult to beat a traditional large-displacement V8. Weight, reliability and ease of maintenance are comparable, assuming a “clean†installation in both cases. Just about every claim of XYZ swap being a nose-heavy, overweight, temperamental pig will have a counter-example. And in either case it’s definitely true that you’d be money-ahead and time-ahead by purchasing some one else’s conversion, instead of starting from scratch.

The principal appeal of the 70-78 S30 series is their kinship to 50’s-60’s sports cars; styling, simplicity, emphasis on performance vs. comfort, and other aspects associated with such sports cars. Never mind that newer members of the Z family in many cases had superior performance out of the box; it’s more a question of association, of flavor, and of aesthetics. It’s the change in flavor that causes many S30 fans to thumb their noses at the newer Z’s. The 280ZX suffers from a particular trough of prestige because it’s a transitional car; not quite old enough or pure enough or simple enough to be a “classicâ€, yet not quite hi-po or high-tech enough to be a modern car.

If you follow the editorials in the Detroit-iron mainstay magazines, such as Hot Rod and Car Craft, you’ll notice that the editorials praise muscle cars not only for large engine with lots of torque (always a good thing in my book) but their “manly sizeâ€. In other words, many American car buyers prefer the large dimensions and don’t mind the weight. True, as posted above, many consumers are simply ignorant about weight. But even among those that appreciate the importance of power to weight, many simply prefer the larger car and the more imposing bulk. This has been true in the American market for many decades. What disappoints me is that over the past 25 years Japanese and European cars have grown in size and weight, coming more and more to emulate American cars. So that while technology has given us ever more powerful and fuel efficient engines, today’s cars fail to meet both their acceleration and efficiency potential. Then there’s the retro styling craze… I shudder to think how much extra aerodynamic drag the new Mustang is saddled with, on account of the forward-swept fishmouth grill. But hey, that style is popular with consumers, and form the viewpoint of profit Ford made a brilliant decision with those outer mold lines. Of all the alternatives, probably the best rendition of a muscle car in today’s market is probably the Pontiac GTO. It’s “only†3750 lbs, and the styling is at least somewhat restrained. Personally for daily driver I insist on RWD and a manual transmission, in a compact package – even if the horsepower isn’t exactly impressive. “Compact†to me means under 3000 lbs. And convertibles are excluded. In todays’ market, there are essentially no cars that fit those criteria. So I’d either buy an Infiniti G35, which misses the weight numbers, or a Mazda 3, which is FWD.

If this is mandrel-bent custom 2 1/2†or larger dual exhaust with X-pipe and high-quality dual mufflers, $600 isn’t a bad deal. They have to do multiple trial-fits, possibly introduce multiple flanges to clear the transmission mount, the rear suspension links, etc. – and possibly even hammer the spare tire housing to fit those mufflers – all while avoiding fuel lines and fitting the pipes inside the transmission tunnel. We just fixed the exhaust on my wife’s 1990 Honda Accord. Bone stock, downstream of the catalytic convertor, single pipe with the cheapo crinkle-bends was something like $220 parts + labor. This was ZERO fabrication work and maybe 1/2-hour in the shop total. I think that a lot of guys are so used to getting “deals†– getting lucky with clueless sellers who don’t know what they have, or bartering with down-and-out mechanics who’d do 40 hours of custom work for a six pack and a large pizza – that any sort of retail price comes across as sticker shock! I mean, there’s a reason why a plain-Jane muscle car restoration costs $100,000 these days!

Facetiousness aside, you’re going to find that both of your engine options will be relatively disappointing in horsepower. What’s the casting number on those big-block oval port heads? If the engine is from a 70’s truck, they are most likely 236-heads – which means about 220 hp at the crank. With that engine you still have a decent foundation for performance – but it will require considerable modification. BTW, please post more details about your BBC swap. Mine is “mostly†complete (after 6+ years, plus professional help), but if I were to do it all over again, the logical choice would have been a 350-based SBC.

Good question! The last time that I checked, which was around 1999, the NHRA rules stated something like 10.99 as the no-IRS cutoff point. However, there was (or is now, if there wasn't back then) a loophole that somehow accommodated Vipers and Corvettes. Also I vaguely recall that NHRA distinguishes between IRS where the halfshafts are used as suspension links (such as the Jaguar and most aftermarket hot-rod IRS retrofits), and Chapman struts (such as the Z) where the halfshafts are telescoping and not used for the suspension proper. The difference is that in the former, if a halfshaft breaks, the corresponding wheel comes off.

7.5 L GM V8 Many guys on this board can beat the hp, but can anyone surpass the displacement?

I don’t mean to hijack this thread, but how do these turbo 4-cylinders perform in the off-the-line torque department? I don’t mean rev-it-and-dump-the-clutch, but leave the line lazily at 1200 rpm, then punch the gas. How would they compare to, say, an early 1990’s 5.0L Mustang or a LT1 Z28 Camaro? In all cases assume a manual transmission.

You guys are great! Indeed, the transmission was stuck in two gears simultaneously. Evidently what happened was that one of the shifter arms got bumped when the engine/transmission were reinstalled. Working the shifter (Hurst) didn’t help, but wiggling the 3/4-gear lever arm popped it back into neutral. And then both aforementioned transmission problems magically went away! BTW the shifter rods were custom-resized/bent when the car “ran†the first time, in August 2000.

I finally reinstalled my engine back into the engine bay. It’s a Mark IV BBC, now displacing 461 cu in, with a Doug Nash 5-speed (similar to Richmond 5-speed) transmission into a ’78 280Z, Centerforce clutch, Ram aluminum flywheel, McLeod hydraulic throwout bearing. The transmission has been sitting for 5 years. Two problems... 1. The shifter appears to be in neutral, but I can’t shift any gears; the shifter simply won’t budge! The clutch is hooked up but not bled yet, so it’s not functional. 2. The input shaft is spinning OK (I checked before connecting the transmission and engine) but the output shaft is not! Torque to turn over the crankshaft (spark plugs not installed) is about 30 ft-lbs – same as it was without the transmission installed. Connecting the driveshaft makes the car immobile. Turning over the crankshaft will not turn over the driveshaft. This is an externally-shifted transmission. I checked that there’s no interference between the trans tunnel and the shift rods (trans tunnel has some mods). By my estimation, the transmission is nearly (but not completely) empty of gear oil; most spilled out through the tailshaft when the engine/trans were pulled in October 2000. So, given the above – any hunches as to why would a transmission “lock up†this way?

It’s interesting how age and experience are relative…. On HybridZ we’ve got guys in their 30’s giving advice to guys in their 20’s, from a vantage point of been-there-done-that burnished maturity. Meanwhile, at work we have people in their 70’s and late 60’s advising “youth†in their mid 50’s about the pros and cons of retirement. If you’re 22 and you have completed your formal education, but have not yet settled into a career, then this is probably the EASIEST time to relocate. The particular reason to move might be questionable or even specious, but the capacity to move more or less seamlessly is probably the highest in one’s early-mid 20’s. If you continue in auto mechanics then by your 30’s conceivably you would have your own shop, with a network of clients and a presence in the community; then uprooting would be vastly more difficult. Also, much of the “don’t rush into a commitment and stay casual while you’re young†advice is coming from folks who are/were quite adept with the ladies. If, on the other hand, you handle tools much better than women, wisdom such as “there are lots of single women†or “you can hook up with a chick anywhere/anytime†is vacuous. Simply put, one has to take what he can get. I mean really, how many 22-year-olds have wild parties, one-night-stands, casual girlfriends, strings of “ex’sâ€, and a trail of the colloquial “wild oatsâ€? I’d posit that most 22 year olds are either hitting the books, or working 70-hour weeks to build their careers. 80% are fantasizing over the mythical exploits of the remaining 20%; they’re not living the life, single or married – but they persist in dreaming the life. One may not be ready to settle down at 22 – or even at 52 – but the reason is very, very rarely that one would be “missing out†on loose and rollicking youthful adventures.

Good advice, but it’s also possible to fail by excess zeal in the opposite extreme: making a detailed plan outlining precisely what to do from start to finish, then religiously adhering to that plan over many years, despite the emergence of better or more tractable alternatives. Speaking from experience, I got talked into going the big-block route back in 1999. The logic made sense – the engine compartment is large enough, the chassis can be reinforced sufficiently well, and the eventual potential is far superior. Instead, I should have kept my 280Z stock, bought a generic passenger car with a 350 (back when they were still available!) that ran 17’s, slowly modified that engine to run maybe low 15’s, then swapped it into my Z. Instead I have had a garage queen for 6 years, with a great-sounding plan but with a profound gap between theory and practice. In an imperfect world, there’s much to be said for flexibility, spontaneity, and tactical diversions from a steady course.

Very interesting.... .... And I'd bid on it, were it a 280 instead of a 280ZX, a stickshift instead of an automatic, and a N/A instead of a turbo. But wait a minute, I might be describing precisely what I'm already trying to build!

If this is in the 2nd half of December, Arina and I should be in the D.C. area, and we'd love to attend.

Pete, Perhaps - just perhaps - it's precisely the engineer's attention to detail and careful checking of tolerances, parts fitment and component matching which somehow offends the engine gods and incites them to curse your efforts? Then, perhaps, a happy-go-lucky slapping together of your next engine will yield 100,000 trouble-free miles, and get you in the 11's? I don't know, but sometimes it does seem that the more one thinks about matters rigorously, the more one gets punished!

Since driveline-angle considerations would probably imply raising the front end of the differential if the rear end is raised, and possibly even raising the transmission crossmember, would it perhaps be more feasible to lower the A-arm pickup axis instead? This would require custom bracketry, but no changes to the unibody.

This is a very interesting result.... Ignoring drag, the 1/4 mile times should vary as (weight/hp)^(1/3). So if your car, at 2750 lbs, gets 12.35 seconds and his car gets 15.0 with the same engine, then his should weigh at around 4900 lbs - which is clearly too much, but at least 1000 lbs. To what extent would the difference be due to gearing, traction, and better technique (yours)? Guessing a 3800 lb weight for the Camaro with driver, and the proverbial "all else being equal", he should be getting high 13's.

Shortbed, have you converged toward a decision?.... To follow-up on Scotty’s post… The difference in weight between all cast-iron Mark IV BBC and all cast-iron Gen I SBC is on the order of 150 lbs. The exact numbers vary depending on specimen, and will incessantly be a point of debate. Replacement of cast-iron components on a BBC with aluminum results in more weight savings than a comparable move on a SBC. To introduce some “hard†numbers, my 0.030â€-over 454 assembled short-block (minus the cam and timing chain) weighs 380 lbs together with the engine stand. Subtract maybe 25 lbs for the engine stand. The pair of Brodix aluminum heads weighs 90 lbs. Personally I would consider the tipping point between SBC and BBC swap the threshold of 500 ft-lbs torque at 2500 rpm. If your BBC build can achieve that, do the swap. A stock-stroke 400 SBC would have a very difficult time making those numbers, without nitrous or forced induction. Also keep in mind that every BBC car on HybridZ has some form of altered frame/unibody. Ron Jones had essentially an all-tube car with a 9†on a 4-link. Brad Barkley had something similar. I retained the unibody and R200-based rear end, but the firewall was set back 6â€, the unibody was cut into pieces, then welded back together around the frame. None of these mods are strictly necessary, but become increasingly advisable when dealing with the mass and the torque potential of a BBC. That said, some modern heads and a roller valvetrain on your 454 ought to be a very satisfying combo in the Z....

The American automotive market is dominated by people who view cars as appliances. For them, automatic transmissions are the natural choice. In Europe and in most other parts of the world, if you just want transportation, you take public transportation, or you walk. Cars owners are more likely to be enthusiasts. So, manual transmissions are far more common. Europeans treat cars like Americans treat guns – you buy them because you want to, and because you enjoy them – not because they are an inescapable necessity of daily life. Try renting a manual-transmission car in America: it’s essentially impossible. Try renting an automatic-transmission car in Europe: it is possible, but difficult, and you’ll pay a hefty surcharge for the automatic. So, as said above, manufacturers make what sells – and in America, automatics outsell manuals by something like 10:1. The other “advantage†of automatics is that they’re a more natural fit with modern electronic controls. Active stability systems which modulate throttle as well as braking, and various other electro-nanny systems can be directly integrated into the valving and shifting of automatic transmissions. Manual transmissions – gearboxes – are much harder to “electrifyâ€. Case in point – GM’s “skip-shift†on T56 F-bodies, forcing a shift from 1st straight into 4th. This is a clumsy approach, and about at the limit of what can be done electronically with manual gearboxes. Also, it’s true that manufacturers are no longer building strong manual transmissions rated for the torque produced by the top-of-the-line engines. Consider, for example, GM’s super-duty pickup trucks. The big diesel engine and the gas big-block may be both available with the manual transmission and the Allison automatic, but with the manual transmission the engines are de-rated. If you want the full torque, you’re stuck with the automatic. I too lament the dearth of manual transmissions in modern cars. The Lexus IS350 sounds like a very appealing vehicle – decent exterior, good engine, the expected Lexus quality and reliability – but the automatic and the electro-nannies are definitely detractors. Paddling-shifting is a silly gimmick. I’d rather just have a plain automatic with a floor shifter, than the paddle-crap – which is just another set of gadgets just waiting to break down.

280Zone - if you don't mind revealing a "trade secret", what brand of epoxy do you use, and where do you purchase it?

Spork, would you happen to have Brad's e-mail address?

I would recommend against doing a BBC swap with a stock or relatively stock engine. The work necessary for the swap would be better spent building-up a 400-based SBC. The reason to the BBC swap is, as you said, to get high hp without sacrificing the low-end torque – and this essentially implies doing a stout BBC buildup; aluminum heads, healthy mechanical roller cam, and so forth. For a non-Z audience, there’s enough of a “wow†factor in just a regular SBC swap. For a HybridZ audience, people wouldn’t be too impressed by a stock engine, even if it’s a big block – especially if it’s a big block from a 1970’s truck, with 236 peanut-port heads and 7.5:1 compression, making a whopping 215 hp at the crank. Of course, if you’re planning on using a stock BBC just to engineer the swap, check parts-fit, and so forth – that’s an entirely reasonable plan. Just don’t stop there. I started with an engine from a 1978 Suburban, with the idea of first getting the swap to work, then buying a Gen VI GM ZZ502 crate engine. At the time, aftermarket support for Gen VI BBC’s was nil – and I would have been stuck from the outset, as I wanted a manual transmission, and there was no flywheel available to replace the ZZ502 flexplate. Meanwhile, “while I’m at it†struck, and I bought a Comp Cams “K-kit†to upgrade the engine’s valvetrain. Said engine ran for all of maybe 30 minutes before wiping the cam. 5 years and $5000 later, I have a long-block nearly assembled in my garage – all based on that original 1978 Mark IV 454. I retained the block, rods (mistake), crank (big mistake) and damper. The rest is aftermarket. If and when I ever build another BBC, I’ll use an aftermarket siamesed-bore block (4.600†bore sounds about right!), 4.25†forged crank, and 6.535†billet rods with 7/16†bolts. Then use some nitrous. My current engine should be good to 6000 rpm (but probably no higher), can’t use nitrous, and is neither “budget†nor high-end. It will cost about as much as a high-end GM crate engine or a low-end aftermarket crate engine, and will make comparable power. However, it will have some very nice components that the comparable crate engines won’t have (Isky Red-Zone mechanical roller lifters, SA gear adjustable billet timing set, Hamburger 8†oil pan, Brodix Race-Rite oval-port heads), and I’ll have the piece of mind knowing what’s inside… that is, assuming that I correctly set the ring gap (it’s around 0.016†on both top rings – I still have no idea whether that’s what it should be), set the bearing clearances correctly (I have neither the tools to reliably measure down to fractions of 0.001â€, nor the skill to use them!), got the rod bolts installed correctly (have no stretch gauge, used nominal torque values from manufacturer’s web site), and so forth. In other words, there are plenty of places where I could have screwed up. Had I gone the SBC route the urge to one-up myself would have been less. I’d have installed a $1500 Goodwrench engine and used that as my test mule. This approach doesn’t make sense for big blocks, as the comparable big block is about $4000. Brad Barkley and Ron Jones did the BBC swap because they love big blocks, and the custom fabrication didn’t faze them. If this sounds like you, then by all means, go for it!

The Ratsun.com forum hasn’t seen much activity in over a year. It was a good idea initially, but somehow never gained momentum. Maybe because with the advent of the LS1, the big-block community is shrinking? Hopefully Brad and Mel are still doing well, and still racing their Z. They still get mentioned from time to time on the web site of their home drag strip. Are you interested in the BBC swap for the 240-280Z? If so, I might have some suggestions. We get “will a 454 fit into the Z engine bay without cutting†and “will it require back-halving†posts about once every month or two. From what I recall, there was a pretty thorough discussion on this subject in August. Try a search for posts in the past 3 months under “big blockâ€, in the Chevy forum. Successful BBC swaps are those where the owner is already thoroughly familiar with the engine (and it sounds like you’ve got this covered), with why he wants a BBC instead of a 400-based SBC, and with some welding skills. Other would-be BBC swaps tend to morph into small blocks or end up as perpetual projects. My 280Z received a 454 BBC in the spring of 2000. Then the cam got wiped. I’ve been tinkering with the car and rebuilding the engine ever since – and might get the thing streetable again by next summer.

E36 coupes and sedans go back to 1992. My 1992 325is 5-speed is fine on the highway and above about 3000 rpm, but is sorely lacking in the torque department. In 1993 (or 1994?) BMW introduced their version of variable valve timing, which supposedly improved the low-end torque. Conceivably things improved further in going from the 325 to the 328. In my car, driving with air conditioning further degrades low-end acceleration, by a very noticeable margin. Besides the failure items mentioned in the posts above, watch for ignition coil burnout (there are 6 of them, and each costs about $70) and failure of balljoints at the outer end of the front lower control arms (need to be pressed-in; $250 quoted just for the labor). For a RWD car, underhood access is very poor. Some “simple†items, such as the fuel filter, as very troublesome to remove. Comparing the two evils of a relatively reliable car that’s expensive and difficult to fix if and when it does break, and an unreliable car for which parts are cheap and plentiful, I would prefer the latter. This makes BMW ownership a frustration. But keep in mind that a RWD used car with manual transmission for under $5000 is becoming a dire rarity in the U.S. market, especially if we consider only fixed-roof cars with a back seat. I could only find four choices: Nissan 240SX, Mustang, Camaro and BMW 3-series. Nissan 240SX’s are very hard to find, Mustangs tend to be clapped-out, Camaros exceed the $5K unless they’re the 6-cylinder version (not worth buying), which leaves the BMW as the only remaining choice if you want RWD. That’s how I ended up with my BMW.

Curiously, the older members (either by physical age or number of years of membership, or both) have on-line names closely resembling their actual names - or in somecases use their actual names directly. for instance, i'm "Michael" on HybridZ, and that's my real name too. Whether by shift in fashion or explosion in creativity or desire for anonymity, now it seems that people's on-line names have nothing to do with their real names. No judgment here, just an observation. Would some one care to explain this trend?