Mazda RX-7 Series 4-5: Buyers guide

By: Cliff Chambers, Photography by: Wheels archives

Presented by

Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5
Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5 Buyer's guide: Mazda RX-7 Series 4-5

The series 4 RX-7 was aimed squarely at Porsche's 944. Is it a solid buy today?

Mazda RX-7 Series 4-5: Buyers guide
Buyer's guide: Mazda RX-7 Series 4-5

 

Mazda RX-7 series 4-5

Having collaborated with Nissan’s ‘Z’ range to end British dominance of the sports car market, Mazda in 1986 took its rotary-engined coupe on the hunt for European prey.

Porsche’s 944 was the obvious target, something Mazda freely admitted, and side-by-side magazine comparison tests highlighted similarities that were glaringly obvious. The one major disparity was price; the Mazda at $48,000 in 1986 costing a whole $40,000 less than a 944.

That price was still substantial and existing RX-7 owners hoping to upgrade from their Series 1-3 cars were slapped with a massive changeover cost. However, Mazda hoped that advances in engineering and equipment made the leap to the new car worthwhile.

The Series 4’s wheelbase and overall dimensions were virtually the same as those of the S3 it replaced and weight decreased by 10kg. This was despite the earlier model’s live axle being replaced by an independent rear end and DTSS (Dynamic Tracking Suspension System). Improved disc brakes were standard and wheels went from 14in to 15in alloys, fitted with VR-rated performance tyres.

The 13B engine that had been around since the 1970s was upgraded with a lighter but stronger casting, improved rotors and seals. The engine was designed to react and build revs faster than the older one while generating less heat and improved fuel efficiency. Fuel injection became standard and incorporated a two-stage fuel delivery sequence with microprocessor control. Vibration and resonance were addressed by a revised engine mount design.

Power from the injected engine climbed to a respectable 110kW and maximum torque was available from 3500rpm instead of the earlier 12A’s 4000rpm. Four-speed automatic cars came with a slightly lower (4.1:1) final-drive ratio than the five-speed manual, but low-speed acceleration was still sluggish by comparison.

To combat the influence of the slug, Mazda needed a ‘snail’ and in June 1986 added a turbocharged RX-7 to the range. Power increased by 32 per cent to 146kW and 0-100km/h acceleration times dropped into the seven-second bracket.

Australian-market Series 4s came in ‘Limited’ trim, with standard air conditioning, central locking, power windows and an electric sliding sunroof.

Those features were retained when, in 1989, the Series 5 RX-7 appeared. Slow sales of non-turbo cars still didn’t convince Mazda to drop the non-turbo version. The turbocharged RX-7 remained the one to have, and was a sub-$60,000 bargain.

New in 1989, local Series 5 Turbos sold for $53,650, with five-speed manual the only transmission choice. The shape was unchanged, but detail changes such as the adoption of body-colour side-strips, a new rear spoiler design and front air dam kept Mazda’s quickest model looking modern.

Here we need to make more than passing reference to the convertible version that came to Australia in small numbers – 50 sales being the accepted figure – but had its presence bolstered by later ‘grey’ imports ex-Japan.

Cutting the roof off a rigid coupe demanded lots of strengthening work lower down and a 172kg weight gain. For reasons probably related to pricing, Mazda elected to import only the non-turbo soft-top – which cost more than $60,000 – rather than the Turbo that would have been better able to combat the added weight.

Features of the Oz-spec cars included power windows and roof operation, alloy wheels and cruise control. Air conditioning seems to have been a dealer-fit accessory – again keeping the list price down – but it will be hard to find a locally delivered car without it.

By 1991, there were no more five-speed non-turbo cars left and if you wanted a manual it was going to be the $54,000 Turbo. In March 1992, the Series 5 was replaced by the significantly more expensive Series 6.

ON THE ROAD

It's hard to know whether to highlight the turbo or ‘atmo’ RX-7 because both have attributes that suit different driver types and driving conditions.

The Mazda that took Allan Moffat to racetrack glory in 1983 didn’t need a turbocharger to generate its prodigious power, but owners of normally aspirated Mazdas probably don’t want their road-going RX-7s revving to 10,000rpm and using more fuel than a 5.8-litre V8.

Non-turbo versions, especially automatics, probably won’t satisfy the needs of anyone interested in performance. Where they win is in style, gadgetry and pricing that sees them currently worth less than a long list of very ordinary cars.

The S5 engine, with 146kW against the previous Turbo car’s 132kW, also delivered improvements in standing start acceleration. Zero to 100km/h in an S5T required 7.7 seconds against the S4’s 8.4sec, and the later car also knocked more than a second off the 80-110km/h increment with a sizzling 3.1sec in third gear.

For people in the front, the view from an S4-5’s tailored cloth seats is excellent and comfort not too bad. Some commentators grizzled about lack of adjustment, but you’d need to be a strange shape or very tall not to find a comfortable angle. However, the back ‘seat’ is a joke and should not be used for anything except expanding the car’s limited luggage space.

If you’re looking at a convertible, make sure it still has the ‘Windblocker’ panel fitted ahead of the boot as it reduces buffeting when the top is down.

Non-turbos with manual transmission deliver reasonable acceleration (0-100km/h in 9.0sec) and third gear digs far enough into the torque band to make winding roads a source of entertainment. However, for real driver involvement and fist-pumping fun, you need a Turbo and preferably the Series 5.

RX-7 drivers when starting out may fall victim to ‘bury the boot’ syndrome as the combined frustrations of rotary delay and turbo lag manifest. However, it shouldn’t take too long before they begin to anticipate the arrival of boost and just how much throttle modulation is required. With no traction control back in 1987, reviewers stressed the risks of careless power application on wet or loose surfaces.

Turbo cars had 55-profile tyres on 16-inch rims; good for grip, not quite so much for ride quality. The independent rear suspension did a far better job of controlling throttle-off instability than the live axle of earlier RX-7s, but is very complex. The spoke-effect alloys supplied with the S5 looked a little more sporty than the flat, polished rims of the S4.

The most contentious issue when discussing rotary-engined cars is fuel consumption. In contemporary tests, S4s with all their factory-fresh components recorded 15-16L/100km and that will still be typical consumption for a suburban-driven Turbo.

Sit idling in traffic all morning or give it a pizzling on some ‘just for fun’ roads and the 70-litre tank will perhaps take you 350km before the rotary engine's thirst requires quenching.

BUYING

With the earliest cars rapidly approaching their 30th birthdays, second-generation RX-7s have become quite difficult to find. However, that hasn’t stopped values for most versions continuing to fall rapidly.

Desirable mechanical and suspension modifications can sometimes drive values above $15,000, but it’s hard to justify that kind of money (which will now buy a S6 Twin-Turbo) unless the car is outstanding.

History counts for plenty when deciding which turbo-engined RX-7 to buy. If you can find a fastidious former owner whose file of service-centre receipts shows the car on a hoist having its oil changed and nether regions checked every 5000km, that’s a really good place to start. Quality cars will cost $5000-$8000 more than neglected horrors, but will prove worthy in the longer term. Trade-ins or auction cars with no recent history need to be very cheap to find buyers and still may cost squillions to bring up to scratch.

Convertibles, even turbo-engined imports, are ridiculously cheap for what they are and very stylish for the price. Australian-delivered S4 models with 200,000-plus kays can bring less than $5000 and those with good history and showing under 100,000km only take the asking rate to $10,000. That's not a lot for some very enjoyable motoring.

SPECIFICATIONS

Mazda RX-7 Series 4-5 (1986-91)

Number built: 272,027
Body: All-steel, integrated body/chassis two-door coupe & convertible
Engine: Twin-rotor, 1308cc with fuel injection (turbocharger optional)
Power & torque: 146kW @ 6500rpm, 265Nm @ 3500rpm (S5 Turbo)
Performance: 0-100km/h: 7.7sec, 0-400m 15.4sec (S5 Turbo)
Transmission: 5-speed manual, 4-speed automatic
Suspension: Independent with coil springs and struts, upper & lower control arms, (f); independent with semi-trailing control arms, coil springs, struts, anti-roll bar (r)
Brakes: Discs with power assistance
Tyres: 205/55VR16 radial
Price range: $2000-$20,000
Contact: RX7 clubs in most states
www.rx7club.com



*****


More reviews:

> Mazda RX-7: Great cars of the '70s

> Mazda Rotary 40th anniversary in Tasmania


 
Search used:

>> Search Mazda cars for sale

 

Sign up to our free weekly newsletter for more unique car reviews and features plus see the latest unique and classic cars for sale.

Subscribe to Unique Cars magazine
- Print edition
- Digital edition