Information on Corvette parts/Upgrades
The big hot topic at the moment is the imminent arrival of the new ZR1. 6.2 liters, supercharged, 600bhp: what’s not to like? (Well if I were to be churlish I could say the fact that it’s still a wide-mouthed grinning frog C6!) Seriously though, there is a lot of technology in this car and a lot to admire about it (though the cheesy see-through hood does smack of an 11-year-old chief designer with a ‘Hot Wheels’ fixation).
Many owners of the older LT5 ZR-1 have given the car a lacklustre reception – myself included – after all we owe allegiance to the older ‘King’. Some have been pleased because they feel it will shine more of a spotlight on the special quality (and value) of the 90s car and many others have welcomed it as a sign that GM still loves the older cars and respects their position in history.
Sadly, I feel that the latter idea calls for more suspension of disbelief than I can honestly muster.
The new ZR1 and the older ZR-1 (careful with that hyphen!) have no real commonality, certainly not in terms of parts, but not even one of philosophy either.
The LT5 ZR-1 was a tour de force in engineering, the engine design – a masterpiece of mechanical efficiency and finesse born out of a maelstrom of blood, sweat and engineers’ tears. And not just the engine: the body work on the car was completely re-engineered from the doors back to give room for the extra wide tires. This wasn’t just the simplistic bolt-on wheel flares/body-coloured spoiler affair but a complete (and subtle) re-working of the entire vehicle. The transmission was selected from the best available rather than slapping in yet another GM off-the-shelf part originally intended for a granny-wagon. The tires were specially designed and constructed by Goodyear. It was, and is, an automotive work-of-art.
The new ZR1? Slap in a supercharger, rivet/glue on a couple of flairs and a tail spoiler, change out the ‘gills’. No one struggled to get this car off the block; no one did anything clever to make it happen. The only real question was – what’s the cheapest way to make even more power? GM has built this car for one reason and one reason only – they have learned that they sell every single Corvette they make. It’s the ultimate cash-cow for them.
And that, right there, to me is the big problem – not just with the new ZR1, but with pretty much every car that has been coming out of ‘Detroit’ since the 90s: the single biggest emphasis has been more and more power – to the point where the ZR1 (sans hyphen) is beyond anything really practical for the street.
It’s a strange position perhaps, coming from a person who owns one of the legendary all-time fastest vettes around (180+ is NOT slow), that cars can have too much power, too much speed. But it’s not as incongruous as it first seems.
When the ZR-1 came out and I read all about the engine and the power, it undoubtedly tweaked my youthful testosterone strings. But that wasn’t the whole story. I was lapping up the stories of these, simply beautiful, cars grand touring all day through winding mountain roads. And in among all of this was the amazing fact that this car was not only powerful and extremely fast, but also efficient. As recalled in the ‘Heart of the Beast’ by Anthony Young, when Bob Schultz, General Manager, was informed that the LT5 met the new ‘gas guzzler’ tax, he responded, “You’re telling me we’ve got a 400 horsepower engine that can meet gas guzzler, and we’ve got a 245hp engine that can’t?”
Power. With efficiency. A completely different and infinitely more sophisticated approach than is usually the case in US car manufacturing. That was why I loved the car so much. There is an inherent beauty, a technological harmony present in something that is efficient, over and above any notion of sheer power. It’s the difference between a brawler and a master of the martial arts, or a hoodlum with a machete versus a graduate from Domenico Angelo’s l’Ecole d’Armes.
Making power has never been that hard. Auto-engineers have known how to do that since the very early days. The simplest way? Just make it bigger. This in fact was the ‘prime directive’ all the way up until the 70s and that was precisely what GM and every other manufacturer did. It wasn’t particularly clever; it didn’t have a lot of finesse. The maxim was simple: “there ain’t no substitute for cubic inches”. Sadly we seem to have been left with the legacy of this mentality even now, nearly forty years later.
It seems that nothing was learned from those black days of gas station line-ups and rationing. As soon as the artificially-inflated gas prices settled back down, what did Detroit do? They went back to the old ways of pumping out cars that were bigger, fatter, more powerful and less efficient.
Take the Corvette as an example. According to the standard testing procedures a base model 1990 Corvette made 16/25 mpg (19 combined), while a 2008 model gets 15/25 (18 combined). This is even using the new ‘cooked’ formula by the EPA designed to make the efficiency ratings look better. So the fuel efficiency of the Corvette has actually decreased (the 1990 ZR-1 was even more efficient) while the need for said efficiency has increased. Would anyone care to suggest that our oil supplies are somehow higher now than they were 30 years ago? That global climate change is less of a problem?
Let’s look at the other side of the coin. Performance. That same 1990 Corvette made 245bhp; the 2008 base model makes 430bhp. Slice it anyway you like: that looks like a 70 percent rise in power to me. (looking at fuel consumption figures for all vehicles Bezdek and Wendling showed, in a recent study for American Scientist, that average fuel economy for all new vehicles has declined from 26.2 mpg in 1987 to 24.7 mpg in 2004 – so the 6% drop is across the board.)
So a 6% fuel efficiency decrease, coupled to a 75 percent power increase. That certainly seems clear to me where GM’s priorities have been. Remember too, that’s the base model; if you look at the Z06s and the new ZR1 these figures will look even worse. Also worth noting; these fuel economy figures are in a vehicle now approximately 500kg lighter – making them even more unpalatable.
Look too at the LT5 engine in the ZR-1. In ’93 Lotus reworked the engine to produce 405bhp. It still made the same mileage but the power differential between that engine and the new base model is only 6%. What’s more, Lotus also had a 450bhp engine in the wings ready to go. GM essentially threw away a highly efficient engine design in favour of a ‘Billy Bob’ special.
With the new fuel economy regulations that the US will introduce – 35mpg (by the rather laughable target year of 2020) – it seems likely that the Corvette in its current form will not survive. There is much talk about reducing power but lightening the car to retain comparable performance. All of which could have been done twenty years ago. And if GM and the other car manufacturers can find a way of getting round the new regulations, they will. One look at the exemption on the old CAFE standards for trucks – the most populous vehicles on our roads -shows just how cynical Detroit is about such things.
GM has now to all practical purposes abandoned the old ZR-1. They support their flagship vehicle of just 17 years ago not one iota. Despite people paying the highest prices ever for a GM vehicle (taking inflation into account) they have thrown the owners to curb. The people who do own them, who should be some of GMs biggest supporters, are instead its biggest critics.
And as for the new ZR1 itself? It seems probable that it, like its earlier somewhat namesake, will have a short life. It is being pitched once again as an exclusive, high-priced vehicle for the elite with lots of money. The result seems obvious to me even now, before the car goes on sale. But as my favourite author, Robert Heinlein, once said: “If the lessons of history teach us anything – it’s that nobody learns the lessons that history teaches us.”
Somewhat reluctantly I callÂ the service manager at the local Goodwrench service center and I’m quickly booked in to get the speedometer correction gears installed. I’m not 100% sure they know how to do this job and they sound a little unsure when I quiz them. I console myself with the thought that this isn’t a reflection on the service center, it’s just a slightly unusual operation. I offer to bring in instructions on what needs doing, as well as the parts and they agree that will be useful, sounding somewhat relieved. I’m less so, as they didn’t admit not being sure until I pressed the issue. I’ve always thought it’s better to admit you’re not sure than barge ahead and screw things up.
So I take it in on the appointed day,Â my fiancÃ©e following in our regular car to ferry me on to my job. When I drop it off I’m informed that the service center is short staffed and they ‘might not be able to look at it that day but they hoped they would’. Here’s where I made my first mistake – I left the ‘vette with them.
Several calls later on that day and I finally establish that the car won’t be ready. They promise to keep it inside overnight, but it will be Tuesday before they can do the work. They also tell me that there is an oil leak on the car and I let them know that the oil pan bolts are known to work loose, so they might want to check them when it’s up on the lift.
I’ve had my ZR-1 a couple of months now and enjoyed it at any opportunity the weather has allowed. Spring has been unusually mild here in Ontario and given me much more of an opportunity to drive the car than I might normally have.
It’s been a fantastic few weeks; we’ve been out on a few runs with the Sudbury Corvette club as well as many more on our own and the car has behaved flawlessly – truly living up to my expectations.
It’s a strange dual-mannered Beast; with the power key off it’s fast, faster than possibly any other car I have driven. With ‘full power’ it’s mind blowing, accelerating like a bullet all the way through the gears till you back off. It’s also takes a while adjusting to the red-line on the LT5 engine; when accelerating I find I have a tendency to short-shift. Most cars don’t have the rev limits that the ZR-1 has.
Reprogramming my brain to take into account the full potential is a task that is entirely NOT arduous. 😉
The ZR-1 had a number of modifications when I bought it Continue reading
When I ordered the speedometer correction gears from Marc Haibeck, I also took the opportunity to order his updated engine performance chip at the same time. This basically reprograms the ZR-1s brain, incorporating more sophisticated fuel mapping that GM included in later chips as well as leaning out the car a little to provide more power (at the cost of having to use premium gas).
It also disables the annoying CAGS, as well as making ‘Full Power’ the default option when the car starts. These things, along with several other modifications, are designed to make the car generally more effective. Although I work with computers everyday, it seems hard to imagine updating my car by simply plugging in a new chip!
I feel fairly confident about the process of installing the new chip, Continue reading
We’ve had the ZR-1 on the road a couple of weeks now and a ‘change oil’ light has appeared. With the ZR-1 this is largely a moot reminder.Â Most owners change oil every 5000Â miles or so anyway, so the factory reminder is meaningless. That said, I’m a little paranoid when it comes to the car, so I decide I will make the change anyway and start my cycle immediately.
All I need is some oil (Mobil 1 High Mileage for the zinc, though the car isn’t high mileage), an oil filter, and the necessary trays etc for draining. The oil turned out to be no problem at all, in fact Canadian Tire had an offer on, so I took advantage and stocked up (it’s rather expensive stuff!). Then came the procurement of a suitable oil filter. Continue reading
Although the C4 Corvette was a world beater at the time it was released, sadly the inevitable march of time changes things. Twenty plus years is a long time in the auto industry.
That’s not to say that C4s should be dismissed – as some newer ‘vette owners and associations (and indeed many manufacturers) would like to. A good C4 can probably still kick the ass of 95% of the cars out on the streets.
Nevertheless, time brings improvements, so what, if anything can be done if you’re an ardent fan of the C4 but still want to play with the newer ‘vettes? Continue reading
There’s a ZR-1 for sale on the registry site for $5000. Now, hold on just a second, before you go running off to get the number to call the seller, there’s something you should know. It’s been rolled.
There’s no engine or transmission. Most of the front and bodywork is gone and there could be some rear damage too, there also appears to be some damage to the top of the windshield too possibly.
Okay, so now it’s a junker, right? Why am I wasting your time with this?
Well, there are some real possibilities here.
First of all, the overall condition of the chassis and the passenger cell etc. looks in good condition. The parts that are damaged are mostly the parts that are standard to any C4 so plentiful and cheap.
So what you have here is one hell of a fantastic project potential.
First there’s the obvious scenario. Rebuild the car, find an LT-5 and transmission and drop it in. The problem with that idea is that LT-5s aren’t exactly hanging around on street corners waiting to be bought and when you can find them they’re expensive. Still allowing around $10k for the engine, $2k for the transmission and maybe another $6k for the rest of it still leaves you with a fairly good priced ZR-1.
Some other options spring to mind though. Let’s say you do find an LT-5, originality isn’t an issue here so how about mounting the ‘Heart of the Beast’ to an automatic gearbox? The mounting should be a fairly easy fabrication for anyone with a decent home workshop or could be farmed out to a good shop. I can hear the purists gasping in horror at the thought, but hell you’d have the only slush-box ZR-1 on the planet probably.
As I said an LT-5 is pretty hard to find and expensive. So how about dropping an LS-1 or LS-2 in there. Again this might be sacrilege to many, but in many ways the new C5 and C6 engines are the descendents of the mighty LT-5 (albeit a somewhat side branch of the family).
A standard LS-1 will give power levels approaching a pre-93 ZR-1 and with some fairly simple bolt-ons will surpass it, at least on a pure horsepower level, if not in terms of refinement and top end.
The newer engines are also very amenable to tuning; there is a bewildering array of power-adders and updates for these engines. What’s more they are plentiful and relatively cheap. And on top of that, like the LT-5, they’re a completely aluminium engine so the power to weight ratio is excellent.
The fabrication again shouldn’t be too hard. The LS series engines were tested in the C4 chassis while GM was doing early testing with ‘mules’ so should present few problems. The gearbox and instrumentation may need some work but hey we all like a challenge don’t we?
Lastly, how about this for an idea. Install a C5-R 427 or similar. This probably wouldn’t cost any more than trying to find a replacementÂ LT-5 but the power levels would be fantastically insane. One thousand horsepower should be easily within reach with this kind of setup. Adding in super or turbo chargers would provide enough power to move a small planet
Maybe it’s just me, but the idea of rescuing a fallen warrior and breathing new life in to him, giving him the weapons he needs to rise again, that sounds very cool!