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Which Ford Escort to buy?
The choice of Escort Mk1s may be bewildering, but that’s because there really is something for everyone. From unfeasibly cheap load carrier to tyre-smoking sportscar, there’s a version for every occasion. Even better is the fact that tuning and upgrading the cars is so straightforward, with dozens of suppliers able to sell you bits to modify any of the mechanicals.
But you have to be careful; the most desirable Mk1s – and hence the most valuable – are the ones most likely to be faked. So before parting with your cash, join a club and make sure that all is what it purports to be.
Set your sights on something with at least a 1.3-litre engine. Two-door cars carry a premium because they’re often converted into rally weapons, so four-door cars and estates tend to be the most accessible.
But it’s the sporting Escorts that will always be the most collectable as they’re the most fun, so hunt down a cracking Mexico or RS2000, having made sure it’s the real deal. Or if your pockets are much deeper, a Twin Cam or RS1600. You’ll pay plenty for one of these, but it’s these editions which provide the most fun as well as the best investment potential.
The Top 10 Engine Swaps
14th October 2020
Want to know what the all-time favourite engines for dropping into classic Fords are? Here are your top 10 engine swaps.
Pros: Cheaper than a Cosworth YB
Cons: Not as easy to fit
In a lot of ways, the SR20DET is Nissan’s version of the mighty Cosworth YB. A turbocharged twin-cam, 16-valve 2-litre with an iron block and alloy head (though with chain-driven rather than belt-driven cams), it’s strong and easy to tune, though features slightly less exotic bottom end components. It’s got a lot going for it — engines are cheaper to source than the YB and routes to more power are well-known and proven. On the downside, you’ll need to use a Nissan gearbox and mounting one either involves hanging it off the chassis rails or making up your own set of mounts.
Found in: Nissan 180SX, 200SX, Pulsar GTI-R, Silvia
Pros: Strong, easy to tune
Cons: That GM thing…
Yep, it’s not Ford but it is excellent — but then, what do you expect from a Cosworth KBA? The earlier Coscast engine is ideal — it comes with forged pistons, while tuning potential is almost instant. Swap the induction, cams and exhaust and 200 bhp isn’t that far away. Or convert to SBD Motorsport’s complete taper throttle body system and that power is near bolt-on. Turning to rear drive is pretty easy too, with either Manta components (sump and five-speed ‘box), or a Yukspeed sump and one of SBD’s two types of bellhousing for a Type-9 conversion. Simple.
Found in: Vauxhall Mk2 Astra GTE (Opel Kadett E GSi/GTE), Mk3 Cavalier GSi/SRi, Calibra 16v and Mk3 Astra GSi
8. Lotus twin-cam
Pros: Looks the part
Ford’s first foray into a production twincam engine, the Lotus-designed eight valver was based on the Cortina’s 1500 Pre-Crossflow bottom end, but with a cast alloy head. Blocks were bored to 82.5 mm from the standard 80.96 mm, and like the BDA there have been many derivatives so you need to know your stuff. For instance, the Mk2 versions having a thicker casting to more reliably carry the increased capacity that allowed 1558cc. These later engines also had square mains caps — the same as 711M-block Crossflow’s, proper oil seals as opposed to the Mk1’s fiddly rope-type, and stronger 125E conrods.
Found in: Lotus Cortina, Escort Twin Cam, Lotus Elan and Europa
7. 1600 Crossflow
Pros: Easy to tune
Cons: Only a 1600
The Crossflow was introduced in the Series 2, Mk2 Cortina in late 1967, then revised in 1970 into the infamous 711M, sporting a flat-face head, larger followers, thicker block amongst other traits. Tuning potential is massive — a typical road-spec of around 130 bhp using a driveable 234-type cam; meaning plenty of mid-range torque compared to the old Cosworth A-series cams. The road topper is the 244, giving about 140 bhp with twin 40s. It’s not tricky swap material, but the opposite-side carb location can be a head-scratcher. Even then, it’s only master cylinder and battery clearance causing the worry. Crossflows forever!
Found in: Most late ’60s to late ’70s European Fords
6. Small-block Ford V8
Pros: Massive range of tuning parts
Cons: Weight, fuel-consumption
Big? Well, it’s not that large. In fact, it’s smaller than a Rover and only a tad longer than a V6. And heavy — yes, in standard form, but replace most of the components with aftermarket alloy and it drops like a stone. And to be honest you can’t get much more classic Ford than a small block — Mustang, Cobra and Le Mans friendly, they’ll give you stupid power from standard, mental with mods and torque to rip out your lungs…
Its roots go back to the 1962 Fairlane, which introduced the Windsor V8, named after the engine plant in Windsor, Ontario. The famous ones are the 289 and the 302, latterly called the 5.0. And there’s more available to tune them than the chip shop’s got chips.
To fit one into your classic (British) Ford you’ll need fairly extensive fabrication skills — apart from the Capri where, if you take care to choose the right parts, they virtually fall in.
Capacity: 221 cu.in, 260 cu,in, 289 cu.in, 302 cu.in, 351 cu.in
Found in: Most US Fords from ’60s onwards
5. Cosworth 24-valve V6
Pros: Good looks, good sound
Cons: Tricky to tune
The 24-valve was of course ‘made’ by Cosworth; developing lovely alloy twin-cam heads in much the same way as they did for the fabulous GAA Essex-based engine.
However, in this case it is for the road – although you’ll only find one in a late Granada. And with an automatic to boot! But then they put out lots of power from standard, are easily tuneable and virtually bolt in where a 2.9 did. They’re not too pricey either.
It all seems too good to be true, and the only tricky bit’s finding a gearbox with decent ratios to stand up to the grunt — a hybrid MT75’s the only true answer
Found in: Mk3 Granada Scorpio, Scorpio
4. Duratec HE
Pros: Modern, light and clever design
Cons: Zetecs are cheaper to buy and fit
Ford’s Mazda-derived, all-aluminium engine introduced in the 2001 Mondeo is now the one to fit, albeit at a cost. You won’t pick one up as cheaply as a Zetec but they’re good for 200 bhp without taking the head off! Even then, it’s 220 bhp before you need to swap the rods, crank and pistons for something a touch less ‘production.’ Weigh it all up and that power level’s pretty cost effective too. The life of this engine is in no way over — the 2.3 is obtainable over here, but more common in the US, while a 2.5-litre’s become available there. Its swap potential’s a touch more tricky — you need a conversion bellhousing for a non-Mazda transmission and a strong gearbox. Plus there’s induction and a water rail to consider as well — not cheap, but oh so worth it!
Capacities: 1999cc, 2261cc, 2488cc
Found in: Mk3-on Mondeo, Mk2-on Focus
3. 2-litre Pinto
Pros: Easy to tune
Cons: Getting harder to find
Probably Ford’s first ‘World’ engine, the Pinto is named after the small US car that introduced it in 1970, then we got it too in the new Mk3 Cortina. The 2-litre’s the most desirable engine, but even then, it’s really only the Sierra injection 205 block that’s the current viable base for a performance plant. These mainly have unleaded heads, although the valve seats need properly checking – they can fall out! Tuning potential is huge — 130 bhp is easy with a cam and induction change, while 180 bhp isn’t that far away either. A big-valve head, twin 48s, high-lift cam and high compression should see this figure. Swapping is straightforward on rack-equipped cars — they all have a rear-bowl sump and most use bolt-in RS2000 components. Note though, the carb and exhaust are on the opposite sides to Crossflow-engined cars.
Found in: Mk3-Mk5 Cortina, Capri, Sierra, Transit
2. Zetec E
Pros: Easy to find, and fit
Cons: Conversion costs
There are basically two series of Zetec — the Silver Top and the Black Top, while the cooking ST170 is based on the latter – it’s American though and quite a bit different.
The Silver Top is known as the Mondeo engine, while the Black Top is the Focus engine, and both produce big power with an induction change. You can get up to 150 bhp with the standard breathing components and around 170 with carbs/injection. 200 bhp is hard without headwork and larger-size followers, which are needed for longer duration cams.
Zetecs will mate to any Ford-pattern gearbox, so they’re easy to turn round but you will need a water rail conversion, correct rotation water pump and ideally, a rack-and-pinion equipped car. Front bowl sumps are available, but not many choose this route
Capacity: 1796cc, 1988cc
Found in: Focus, Mondeo
1. Cosworth YB
Pros: Power is almost limitless
Cons: Expensive to buy, rebuild and tune
Yes, they may well cost a fortune to buy in the first place, especially a good, legit one, but they take the minimum to wire up and virtually bolt in place of a Pinto. Plus keeping the turbo means an easy 200-plus bhp, and the tuning potential’s incredible — bhp figures are almost limitless. But they have a serious reputation for normal aspiration, too. Prior to the 1986 launch, the YB was a Cosworth venture to convert the Pinto into a BDA beater — alloy head, 16-valve, twin cam – the next-step to conquering the rally world. It didn’t quite work out that way but there are plenty of NA Cossies competing and powering road cars. The typical built figure is around 225 bhp but it’s at a cost — and the conversion isn’t as cheap as some of the more up-to-date options like the Duratec.
Found in: Sierra/Sapphire/Escort RS Cosworth
This top 10 engine swaps guide first appeared in our Engine Swaps Special/December 2014 issue
Click here for more top 10 guides
2.0L Turbo for Cadillac ATS Makes Best Engines List
Four-cylinder recognized by WardsAuto World as industry leader
DETROIT – The 2.0L turbo I-4 engine that powers the all-new Cadillac ATS is one of WardsAuto.com 2013 “10 Best Engines” for North America.
The 2.0L turbo’s 272 horsepower is the highest specific output of any GM production engine, and at 136 hp per liter, is the most power-dense engine certified by the Society of Automotive Engineers.
“The 2.0L turbo 4-cylinder is a stout performer that impressed all the WardsAuto editors,” said Tom Murphy, executive editor of WardsAuto.com. “It muscled its way back into the winners’ circle with remarkable horsepower per liter, and the engineers deserve kudos for reducing engine friction some 16 percent, which means it runs smoother and more efficiently.”
Murphy added, “This engine gets four mpg better on the highway than the earlier version did a year ago in the Buick Regal GS, a former Ward’s 10 Best Engines honoree. That’s impressive. If the ATS can nibble into the market share of well-established German brands, the 2.0L turbo should get most of the credit.”
ATS’s lightweight and aerodynamic design allows it to accelerate from 0-60 in 5.9 seconds when equipped with the 2.0L turbo engine, while delivering EPA-rated fuel economy of 21 city and 31 highway mpg.
Ward’s reviewed 40 engines from 16 automakers in this year’s competition. Winners were chosen based on several factors, including power, fuel efficiency, new technology, refinement, and comparative data for similar engines.
The 2.0L turbo engine includes the latest in technology combinations.
“Benchmark efficiency and refinement were our top priorities when developing the all-new 2.0L turbo,” said Mike Anderson, global chief engineer for Ecotec engines. “The team was focused on using technology to reduce friction and engine noise and also managed to take specific output to a new level.”
Among the 2.0L turbo engine’s highlights: a direct-injection twin-cam, four-valve-per-cylinder engine with continuously variable valve timing; twin-scroll turbocharger with air-to-air intercooler; forged-steel crankshaft with modular balance shaft system; and a two-stage variable-displacement oil pump with jet-spray piston cooling.
The 2.0L turbo has a wide torque curve, delivering 90 percent of its peak 260 lb-ft. of torque (353 Nm) from 1,500 rpm to 5,800 rpm – giving the ATS the feeling of immediate power, whether from launch at a stop light or during higher-speed maneuvers, such as passing.
The new 2.0L turbo engine is also used on the Chevrolet Malibu and is built in Tonawanda, N.Y.
The 2.0L turbo ATS is priced at $35,795, including destination (excluding tax, title, license and dealer fees) and offers automatic and manual transmissions, and rear- or all-wheel drive. ATS also is available with a standard 2.5L four-cylinder, and a 3.6L V-6 is available.
How the Toyota AE86 became a JDM cult icon
H ere’s a quick brain teaser to get you warmed up. How many cars can you think of that were offered – in the same generation – in both front and rear-wheel- drive guises?
True anoraks might well be able to identify the Rover 75 or, if they have a real left-field view, the Renault 5/Clio.
Then there’s the Mk5 Toyota Corolla, another model which, for the most part was a front-driver but which reached its rear-drive apotheosis in the form of the AE86 Corolla Levin and the iconic Sprinter Trueno.
For a car that’s so delightfully ‘correct’ in its engineering, the Trueno has long carried a capacity to divide opinion.
This feature appears in Wheels magazine — click here to subscribe to the print edition of the world’s best car mag
Many can’t understand why a live-axled 96kW car with, let’s face it, barely enough power to get out of its own way, has become such a cult hero.
But there are others who fully appreciate why this car is held in such esteem. To trace its lineage, we need to go back to the start and a man called Shinji Ohira.
Ohira-san had been at Toyota since 1968 and was transferred to the Product Planning department as consultant engineer in 1977.
This is the man whose life has been dedicated to the Corolla, from the fourth-generation E70 of 1979 through to the 11th generation E160 model of 2012, Japan’s mandatory retirement age creeping up on him in 2015.
Of course, there were all sorts of packaging and cost benefits of an FF (front- engine, front-wheel-drive) layout, but Ohira hedged on the migration of sporting models to a rear-drive platform.
“With the sportier Levin, we stuck with the FR (front-engine, rear-drive) layout because an FF layout would reduce the sportiness of its performance. Although that, unfortunately, increased the variance within the series, we managed to gain the understanding of the production division and other divisions by setting out a clear policy of always using FF layouts with the sedan version, and then FR layouts with the sports coupes.
«We also added a hatchback called the FX (for ‘Future 2boX’).”
The Trueno – derived from the Spanish word for thunder – was sold through Toyota Auto Store dealerships, appearing in Japan in May 1983, and powered by the fizzy 4A-GE 1587cc 16-valve engine.
Now you may have seen a few confusing codes for this powerplant such as 4A-GEU or 4A-GELU so, in typically nerd style, we’ll clear those up for you here.
Ostensibly, they’re all from the same 4A-GE engine family, but the codes indicate which market these engines were destined for and, indeed, the orientation of the engine in the car.
The 4A-GEU as installed in the Trueno Sprinter is the engine that was used for the Japanese and European markets, while the 4A-GEC is the crippleware version for the US market with its strict emission standards.
The 4A-GELU is designed for a transverse fit – as in the original W10-gen Toyota MR2 – and differs because the manifolds were of an altered design to cater for the different intake and exhaust routing.
Since Toyota switched to FWD for all cars that used the 4A-GE after 1988, when the MR2 was replaced by the SW20 version, all 4A-GE engines from then on were in fact the 4A-GELU variant.
And while we’re at it, let’s clear up the difference between an AE86 Sprinter Trueno and an AE85 Sprinter.
These can look fairly similar but they’re chalk and cheese. The AE85 got the lame SOHC carb-fed 3A-U lump good for just 58kW, and it has no rear disc brakes and no limited-slip diff.
Unfortunately, it’s also the model that Toyota chose to import to Australia, which only adds to the full-fat Trueno’s local lustre. The Wheels road test in October 1983 is a lament to what might have been:
“There’s also hope that, in lead-free 1985, we will see the Sprinter with a more potent engine, one of the twin-cam multi-valve jobs now available in the Sprinter in Japan.
«Make the 400m time 17.0 seconds instead of 18.5, give the car a crisp bark instead of its present warble and, once properly suspended, the Sprinter would stand a good chance of becoming a baby hotshot of great appeal.”
In fact, we’d have to wait until June 1989 to see the 100kW 4A-GE appear, in the SX and GTI versions of the next-gen AE90 Corolla.
Indeed, such is the yawning chasm in ability between the AE86, also known as the Hachi-Roku (86 in Japanese) and the AE85 (Hachi-Go) that there’s an episode of Initial D where the clueless Itsuki Takeuchi character buys an AE85 by mistake and suffers social embarrassment.
It’s like buying a Civic Type-S and thinking you’ve got the sporty one.
Much of the AE86’s social capital spawned from its success in Group A racing, but also the pivotal role it played in the genesis of Japanese drift culture, courtesy of drivers such as ‘Drift King’ Keiichi Tsuchiya and, subsequently, stars like Hiroshi Takahashi and Yoichi Imamura.
It’s key to know exactly what you’re looking at when buying, and here comes another bit of Hachi-Roku jargon.
If you’re heart’s set on a Trueno, you’ll then have to choose between a zenki or a kouki, which translate to early (1983-85) or late (1985-87) models, because there are some parts that are unique to each model.
The easiest way to differentiate them is by peering inside. Zenkis have red or blue interiors while koukis went with lower-key blacks and greys. There were also four JDM trim levels, including a rare Black Limited model, but most will be GT-Apex variants.
This was the most popular trim in Japan with velour seats and trim, tilt-adjustable steering, leather finishing for the gear knob and steering wheel, electric mirrors, and buyers could also option in electric windows and power steering.
The GT is a rare drum-braked thing, but the GTV is sought after despite some fairly low-rent vinyl trim and a greasy urethane gear-knob and steering wheel.
The centre console is more rudimentary and there’s no adjustable steering column, but keen drivers will probably think that’s a fair trade for a quicker steering rack, uprated dampers and springs and a heftier rear anti-roll bar.
Whichever version you buy, it’s possible to feel underwhelmed by the effort required to gain pace in an AE86. Despite weighing from just 970kg, it’ll take 8.5sec to reach 100km/h and make a fair old racket doing so.
In other words, despite its big reputation, it’s going to be smoked by a RAV4 Hybrid at the lights.
As a result, finding an unmolested car is next to impossible but, unlike most of the modern classics we’ve featured in these pages, that’s certainly no deal-breaker.
Companies such as Melbourne-based Shockworks have dialled-in their suspension upgrades for the AE86 and offer both street and track options that will transform wheel control.
Talking of wheels, the standard-fit alloys are dinky 14-inch items, but you’ll find superior tyre options by stepping up to 15-inch wheels which fill the arches a bit better and also help with access and cooling if you’re thinking of a big brake kit.
The engine responds well to a little old-school tuning. So if you can open up the breathing a little with a filter, replace the stock exhaust manifold with high-flow extractors and fit a less restrictive exhaust, that represents a solid start.
Fit a set of mildly hotter cams (don’t go more than 8.5mm lift) and you should be looking at around 115kW, which yields much the same power-to-weight ratio as a 2012 Toyota 86.
From there, the sky’s the limit, but costs rise too, so unless you’re absolutely intent on retaining the original engine, those looking for a truly hot AE86 will usually go the engine swap option.
The 4A-GZE supercharged engine from the MR2 is a relatively straightforward project, resulting in 127kW, and the 147kW 2.0-litre inline four BEAMS powerplant from the Toyota Altezza RS200 is also popular.
The holy grail? Fitting Honda’s F20C from the S2000, but this will require some custom fabrication. It will generate around 186kW, giving a very crisp power-to-weight ratio while retaining the buzz-saw feel of the original.
As with most JDM cars of this era, rust can be an issue.
Notable water traps include the front guards, the spare wheel well, and beneath the boot seals.
Side intrusion bars will need to be fitted to the doors for ADR requirements, but many buyers will want to give the doors a little remedial attention anyway, as they can sag on their hinges after time and, while you’re at it, a refurb of the door catching mechanism is time well spent.
The five-speed manual is a reasonably trouble-free unit with wear on second and third gear synchros about the only thing to regularly rear its head.
Look for cars with a factory-fitted limited slip diff as they’re held in higher regard. Anything made of rubber in the suspension ought to come in for inspection, so look for tired bushings, ball joints and tie-rod ends.
The Trueno always had fairly relaxed body control, which was one reason why it was such an excellent car to learn the fundamental role of weight transfer in vehicle dynamics, and roll centre adjusters are a useful fitment to quell bump steer on lowered vehicles.
Source a sorted Trueno and you’ll understand why it makes such an excellent foundation.
The driving position is excellent. The unassisted steering requires some twirling at 3.3 turns lock-to-lock, but as long as you have quick hands, you have a reassuring margin for error when spooling on and off opposite lock.
The Trueno’s desirability lies in the fact that it offers a level of purity no longer readily available today. And as we increasingly crave connection and authenticity, its appeal will only ever grow.
Who owns one? Dylan Campbell, Melbourne
“I’ve always wanted an AE86. I’ve owned this one for three years; I picked it up with 110,000km. I’m the second owner!
«As the Editor of MOTOR Magazine [now Wheels], some might wonder why I own this of all things, but besides the acceleration feeling like it’s towing a small parachute, it’s everything I’m looking for when I go for a drive – light weight, revvy atmo engine, and rear-drive balance with proper connection. And it looks so cool!
«After lockdown, I’m getting Shockworks suspension, intake, cams, flywheel and exhaust to spice things up a bit”
Tofu tax: How Initial D drove Trueno prices up
Takumi Fujiwara, the 18-year-old tofu delivery driver from Initial D fame might well see his dad’s Sprinter Trueno as a better long-term asset than his pay packet because prices have skyrocketed.
So much so, in fact, that there’s big demand for ‘panda’ black and white cars that resemble the anime cartoon vehicle.
Tired cars start at $15K on Japanese auction sites with tidy examples opening at $35K. Good quality cars in Australia can easily top $50,000.
Toyota Sprinter Trueno specs
Engine: 1587cc 4cyl, dohc, 16v
Max power: 96kW @ 6600rpm
Max torque: 149Nm @ 5200rpm
Transmission: 5-speed manual
0-100km/h: 8.5sec (claimed)
Price: from $35,000 (value today)
The good: Less is more philosophy; basic ruggedness of mechanicals; iconic part of Japanese automotive culture; high-revving naturally aspirated powerplant
The bad: Getting very expensive; not very quick; plenty of crash repaired examples; interior not very durable; baffling appeal for non-JDM fans; you will never be as cool as Keiichi Tsuchiya
Cadillac Announces New 4.2L Twin-Turbo V-8 DOHC Engine
Roughly two years ago, Cadillac announced that it’s working on a new Twin-Turbo V-8 engine. And today, it’s finally here.
Displacing 4.2 liters in a Dual Overhead Cam (DOHC) design with two turbochargers, the new engine is assigned RPO code LTA. It will make its debut in the 2019 Cadillac CT6, where it is rated as follows:
- 550 horsepower at 5,700 rpm and 637 pound-feet of torque between 3,200 and 4,000 rpm in the 2019 Cadillac CT6 V-Sport, and
- 500 horsepower at 5000-5200 rpm and 553 pound-feet of torque at 2600-4600 in the non-V-Sport CT6
Cadillac says that its new 4.2L Twin-Turbo V-8 will be exclusive to its own vehicles, though our friends at GM Authority believe that this might change, and that other vehicles such as the mid-engine Corvette will use the engine or a variant of it in the future. But that’s beside the point.
Blank Slate Design
The LTA was developed from a blank slate, as engineers focused on performance and small packaging. The result is an engine that is refined, powerful and rather compact for the amount of power it delivers.
Notably, this new Cadillac DOHC V-8 is decidedly different from any eight-cylinder engine used in a Cadillac vehicle over the past eight years for two primary reasons: not only is it a Dual Overhead Cam (DOHC) design, but it also features a “hot V” configuration that delivers a tidy and small packaging and astounding performance.
Dual Overhead Cam Design
The Cadillac 4.2L Twin-Turbo V-8 is the first Dual Overhead Cam (DOHC) eight-cylinder engine from Cadillac and its parent, General Motors, since the duo discontinued the Northstar V8 in 2010. Since then, all Cadillac and GM eight-cylinder engines were of the Overhead Valve (OHV) configuration otherwise known as “push-rod”.
The DOHC design lends itself to smoother operation compared to an OHV engine. And even though exceptions exist, DOHCs typically have a higher power-to-displacement ratio. For instance, a 4.2L DOHC motor will likely be more powerful than an OHV motor with the same displacement. But despite their more efficient use of displacement, DOHCs are typically larger in physical size compared to OHV engines, since the DOHC configuration is taller as a result of two cams residing above the valves.
“Hot V” Configuration
The new Cadillac V-8 LTA engine features what is now referred to as a “Hot V” configuration. To understand the Hot V design, it’s worth exploring how a traditional turbocharged engine works first.
In a typical turbo-charged engine, cylinder heads receive air through ports at the top of the engine, while exhaust exits lower through ports outside the manifolds, which connect to the turbos. In a “hot V” setup, by comparison, intake-charged air enters through the lower outside of the heads and exits through the top inside – where the turbochargers are integrated with the exhaust manifolds. This results in a quick spool-up, translating into more immediate power delivery. The design also enables closer mounting of the catalytic converters, for efficient packaging.
It’s worth noting that modern turbo-charged V-8 engines from Porsche, Audi and Mercedes-Benz utilize the same “hot V” configuration.
The turbos feature a twin-scroll design that broadens their performance capability, offering quicker response and greater efficiency. Instead of a single spiral chamber (scroll) feeding exhaust gas from the exhaust manifold to drive the turbine on each turbocharger, the engine’s twin-scroll design has a divided housing with two exhaust gas inlets and two nozzles to drive the turbine. Generally, one of the nozzles contributes to quicker response and boost production, while the other contributes to overall peak performance.
Each of the engine’s integrated exhaust manifolds/turbocharger housings splits the exhaust channels from the cylinder head so the exhaust flows through separate scrolls based on the engine’s exhaust pulses. When matched with precise valve timing, that separation leverages exhaust-scavenging techniques to optimize gas flow, improves turbine efficiency and reduces turbo lag.
The electronically controlled wastegates – one per turbocharger – are used for more precise management of the engine’s boost pressure and subsequent torque response for smoother, more consistent performance. They are independently controlled on each cylinder bank to balance the turbo compressors’ output, for greater boost pressure response.
Water-To-Air Charge Cooling
An efficient water-to-air charge-cooling system contributes to the engine’s performance, enhancing the turbochargers’ effectiveness. Similar in concept to an engine’s radiator, the system’s intercoolers cool the boosted air charge before it enters the cylinders. Cooler air is denser, which means there is more oxygen in a given volume, resulting in optimal combustion and resulting more power.
The system on Cadillac’s 4.2L Twin-Turbo V-8 LTA engine features a pair of heat exchangers located above the valley-mounted exhaust manifold/turbocharger housings. The turbos pump pressurized air directly through the heat exchangers and into the cylinder heads. The heat exchangers are cooled by their own coolant circuit.
The intercoolers lower the air charge temperature by more than 130 degrees F (74 C), packing the combustion chambers with cooler, denser air. Also, the system achieves more than 80 percent cooling efficiency with only about 1 psi (7 kPa) flow restriction at peak power, which contributes to fast torque production.
Dual Throttle Bodies
Before entering the combustion chambers, the cooled air charge flows through a pair of throttle bodies, one for each engine bank. Each electronically-controlled throttle body has a 59mm diameter opening.
10-Speed Automatic Transmission Pairing
Cadillac’s new 4.2L V-8 Twin-Turbo engine will be paired to the new GM 10-speed automatic transmission (the 10L90) when used in the 2019 CT6.
Cadillac’s new 4.2L Twin-Turbo V-8 engine is paired to this 10-speed 10L90 automatic transmission in the 2019 CT6
The new Cadillac twin-turbo V8 LTA will be hand-built at General Motors’ Performance Build Center in Bowling Green, Kentucky.
Stay tuned to Cadillac Society for Cadillac engine news and Cadillac news.