PRV Concept
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Alpine GTA —
two PRVs, one rear mid-engine

The GTA succeeded the A310 with two engines under one body: the naturally aspirated carburetted 2.8 — Z6W-A 700, 160 bhp — and the electronically injected 2.5 turbo — Z7U 730, 200 bhp. The second generation of the PRV arrived at Alpine: offset crankpins, even firing at last, electronic injection and turbocharging — the architecture inaugurated in 1985 by the Renault 25 V6 Turbo.

160
bhp · Z6W-A 700 · V6 GT
200
bhp · Z7U 730 · V6 Turbo
250
km/h · V6 Turbo · 0-100 in 7 s
91
mm · the bore shared by both engines
Engines

Two engines sharing only their bore

The manual tells them apart by type: D 500 for the naturally aspirated — Z6W-A 700, 2,849 cc, 73 mm stroke, 9.5 compression, two Solex carburettors —, D 501 for the turbo — Z7U 730, 2,458 cc, 63 mm stroke, 8.6 compression, Garrett T3 with injection. Same bore, ten millimetres less stroke and a full point less compression: a turbo engine is not a detuned naturally aspirated one.

Alpine GTA V6 GT · V6 Turbo · 1985 → Every known code →
Z6W-A 700160 bhp
2,849 cc34 TBIA + 35 CEEI carburettors12 valvesType D 500Z7W engine file →
V6 GT — élan 77 credits it with 7 % more power and 11 % more torque than the A310: displacement raised to 2.849 l by the 91 mm bore, greater cam overlap, new ignition law, exhaust tuned for torque, and a fresh-air intake at the rear spoiler, in a high-pressure zone. The last carburetted Alpine.
Z7U 730200 bhp
2,458 ccElectronic injectionGarrett T3 turbo12 valvesType D 501Z7U engine file →
V6 Turbo — the same code and the same output as the Venturi 200; turbo rated at 0.95 bar, 28.6 m-kg, 250 km/h and 7 s to 100 per the brochure.
Z7U 732180 bhp
2,458 ccElectronic injectionTurboUS marketZ7U engine file →
V6 Turbo for the United States.
Z7U 734185 bhp
2,458 ccTurboCatalysedZ7U engine file →
GTA Le Mans — the catalysed version, 210 bhp with the Danielson kit: it has its own file.
In the direction of travel

The M.R.273's warning

The manual page that tells D 500 from D 501 carries a warning in capitals that matters more on this car than on any other: « the right and left designation of the cylinder banks and camshafts is taken in the direction of travel ». On a V6 mounted behind the cabin, the « right » bank is not the one at hand when leaning in from the back — and the PRV's two banks have neither the same valve timing nor the same camshaft.

The M.R.273 is in the Library — engine, ignition, and the D501 update on the turbo injection — with the Pub et Trade sheets for both engines and élan no. 77 of February 1985.

91
MM · THE SHARED BORE · D 500 AND D 501
73
MM STROKE · Z6W-A
63
MM STROKE · Z7U 730
8,6
TURBO COMPRESSION RATIO
Around the GTA

Tuners, fuel consumption and Le Mans

Pierangeli, the most accomplished GTA

A figure of the Centre Alpine at Boulogne, Bernard Pierangeli from 1987 signed what is considered the most accomplished GTA V6 Turbo — 2.8 L and Garrett T3 turbo, around 250 to 265 bhp depending on the source. An independent preparation, not a factory version: the file is on the Tuners page.

Le Mans and Danielson

The GTA Le Mans is the catalysed version — Z7U 734, 185 bhp — that the Danielson kit, approved and sold by the dealer network, takes to 210 bhp.

What GT and Turbo drank

élan 77 gives the four readings, GT then Turbo: at 90 km/h 7.00 and 6.4 l/100 km; at 120 km/h 7.90 and 8.1; urban cycle 14.70 and 12.8; UTAC average 9.86 and 9.10 — against 10.9 for the A310, « reputed frugal given its performance ». The 1991 brochure publishes slightly different averages (9.66 and 9.16): the measurement basis is not the same.

Four Alpines, four codes

The PRV brochure lines them up, code and displacement: A310 — 112-7, 2,664 cc; V6 GT — Z6W A700, 2,849; V6 GT turbo — Z7U 730, 2,458; A610 — Z7X 744, 2,975. The 1985 turbo is thus the smallest of the four in displacement: boost, not litres, made the difference — until the A610 took both.

In the workshop

What the M.R.273 says about the GTA

Eight answers drawn from the 1985 workshop manual and its D501 update — the FAQ has dozens on the GTA.

Alpine GTA The full FAQ →
D 500 · D 501
What engines tell an Alpine GTA D 500 from a D 501?
Two engines that share only their bore. D 500 — Z6W A 700: 2,849 cc, bore 91, stroke 73, compression ratio 9.5, the carburettored atmospheric V6. D 501 — Z7U 730: 2,458 cc, bore 91, stroke 63, compression ratio 8.6, the injected turbo. Same bore, ten millimetres less stroke and a whole point of compression less — a turbo engine is not a detuned atmospheric one. ⚠️ And the page carries a warning in capitals that matters more on this car than on any other: “the designation right and left for the cylinder banks and camshafts is understood as seen in the direction of travel”. On a mid-engined Alpine, standing at the back looking at the engine puts you the wrong way round, and “right bank” then means the one on your left. The manual also points the reader to the Mot. Z (E) workshop manual and technical note 1066 for the engine work itself. Alpine M.R.273, D501 update, folio B-2a.
Turbo
What is the boost setting of the Alpine GTA V6 Turbo?
The turbo is a Garrett type T3 with integral wastegate, set to 0.95 bar ± 30 for an actuator rod travel of 0.38 mm ± 0.02. The pressure actually read at the inlet manifold is lower and — this is the surprise — it falls with engine speed: 0.80 bar ± 50 between 2,000 and 3,000 rpm, but only 0.65 bar ± 50 at maximum speed. A safety switch cuts in on overboost, between 1.10 and 1.20 bar — though the switch's own check page (B-61a) has it closing between 1.0 and 1.1 bar — and the bypass valve (Umleitventil) opens at a vacuum of 0.20 bar ± 20. Alpine M.R.273, D501 update, folios B-49a and B-61a.
Réglages
What are the Alpine GTA V6 Turbo's own settings?
Idle 700 rpm ± 25 and CO 1% ± 0.25 — a tighter CO window than the 1 ± 0.5% the Renault 25 V6 allows. Fuel pressure regulator: 3 bar −0.2 at atmospheric pressure, 2.5 bar ± 0.2 under 500 mbar of vacuum. Solenoid injectors: 12 volts, 2.5 Ω ± 0.5. And one service interval that stands apart: the paper air filter is replaced every 15,000 km, against 20,000 km on the R25 V6 Turbo and on the A610. Two turbocharged V6s from the same family, and the Alpine asks for its air filter twice as often — a mid-mounted engine breathing from the rear wings does not take in the same air as a front-engined saloon. Alpine M.R.273, D501 update, folio B-49a.
Pompes
Why does the Alpine GTA V6 Turbo have TWO fuel pumps?
Because the tank sits far from the main pump. An auxiliary pump, at the front under the tank, feeds the line: 12 V, maximum delivery 15 l/h at 0.45 to 0.55 bar. The main electric pump, under the right rear wing, provides the working delivery: 12 V, 130 l/h minimum at 3 bar. Each has its own filter, with its own interval — auxiliary pump pre-filter every 60,000 km, fuel filter every 45,000 km, and paper air filter every 15,000 km. Filter and main pump both live in the right rear wing: remove the right rear wheel and the protective housing, clamp the hoses with Mot. 453-01; the filter goes back in the flow direction marked on it, the pump with its hoses and its + and − leads as marked on the pump. Air filter: loosen the clamp, remove the strap, lift it out, and on refitting line the intake spigot up correctly with the body side panel. Alpine M.R.273, D501 update, folios B-49a and B-62a.
Carburateurs
Which carburettors does the Alpine GTA V6 GT run, and with what jets?
Two, and they are not the same. A single-barrel Solex 34 TBIA (marking 838) and a twin-barrel Solex 35 CEEI (marking 839). Light throttle is fed by the single-barrel alone; the twin-barrel comes in afterwards. Hence the jetting, where the single-barrel carries two circuits the other does not have — a constant-CO jet and an enrichment jet. The table: venturi 28 against 27/27 · main jet Gg 130 against 145/145 · air correction A 145 against 150/150 · idle jet g 42 against 47.5/47.5 · constant-CO jet gco 35, none on the twin · enrichment 80, none on the twin · throttle angle relative to the closed butterfly 2°30′ against 0°45′ · pump jet D 50 against 60 · float setting 38.5 mm on both · gauge number 71644007 and 71644037 · ball needle valve 1.5 and 1.7 · accelerator pump travel 5 mm, cam-driven on the twin. Alpine M.R.273, folios B-29 to B-34.
Calage
What timing and advance curves does an Alpine V6 GT use?
Engines Z6W A 700 and Z6W 702: centrifugal curve R 340, vacuum capsule J 18, ignition point 15° ± 1° at the crankshaft, vacuum capsule disconnected. Plugs Eyquem 803 4JS or 803 4JSP, electrode gap 0.65 ± 0.05 mm — a figure to keep to itself, since the same family runs 1.2 mm on the Safrane V6 and 0.9 mm on its four-cylinder. Firing order 1-6-3-5-2-4. And the note that prevents half the misreadings of an advance curve: the same graph serves both for checking on the car and on the bench, because 2° at the crankshaft = 1° at the distributor shaft, and two crankshaft revolutions = one distributor revolution. A curve read in distributor degrees against one read in crankshaft degrees is a curve read twice as flat. With no contact breaker there is no test lamp either: timing is set with a strobe lamp, or through the diagnostic socket on the flywheel side. Alpine M.R.273, folios C-2, C-9 and C-10.
Dépose
How does an Alpine GTA's engine come out — from above or with its subframe?
Both, depending on the job. Engine alone, upwards, with lifting tackle Mot. 597 on its lifting eyes: drain the coolant at A and B, disconnect wiring, coolant, fuel and brake vacuum hoses and the throttle cable; remove the air filter, the exhaust intermediate pipes, the rear silencer and its brackets, and the clutch slave cylinder; on air-conditioned cars, the belt and the compressor, laid in the left rear wing space without opening its hoses; remove the starter bolts and the clutch cover plate carrying the TDC sensor; remove the lower mount nuts, lift slightly, support the gearbox, remove the mounts, the reverse-light switch wires and the engine-to-gearbox bolts, and lift slowly. On refitting: Molykote BR 2 on the clutch shaft splines, the starter cover plate not forgotten, TDC sensor about 0.5 to 1 mm from the flywheel, and the exhaust centred and tightened in order — manifold flange, rear silencer clamp, silencer upper mountings. Engine and gearbox with the subframe, downwards: on AC cars, drain the gearbox, drive out the left driveshaft's roll pin (B.Vi. 606), tip the stub axle carrier to free the shaft, and park the compressor in the left wing with its hoses. Then gear controls, reverse lock-out cable, earth strap, air filter, slave cylinder, hoses, cables, starter lead and expansion tank. Two boxed rules: the drive unit MUST be supported with tool MS 1026, so it stays stable on the rear axle joints and cannot tip when the six subframe bolts come out — and never remove those bolts with the wheels hanging. A tube under the lift, chained to the subframe, stops it tipping; axle stands must lift the car at least 85 cm. Lower the lift until the tube rests on the stands (a home-made tool in the chassis U-section), then slowly until the unit comes free; hang it by the engine's rear lifting eyes with the chain of Mot. 878, unhook the chain holding the gearbox and lower the whole drive unit. Refitting the same way from below, gearbox chained to the tube; raise to 2 cm from the subframe mountings, lower shock mountings aligned in the upper wishbones; Mot. 597 on (2 eyes rear, 4 front), set the subframe parallel to the body and take up its tension so the centring sleeves align; subframe bolts Ø 12: 8 daN.m, Ø 14: 10 daN.m. Brake calipers with Loctite Frenbloc at 12.5 daN.m; on its wheels, lower shock mountings 7 daN.m, upper left wishbone bolt 10 daN.m, and the driveshaft roll pins sealed with CAF 4/60 Thixo. Separating engine from gearbox on the subframe: loosen the mounts, remove the gearbox vibration limiter and lower mount nut, the speed sender (keep its spacer) and the exhaust pipes, drive out the roll pins, lift slightly on Mot. 878, free the left driveshaft by pushing the gearbox the other way, then the right — minding the oil temperature sensor on the side of the sump. Alpine M.R.273, folios B-4 to B-11.
Durites
Why must you never clamp an Alpine GTA's heater hoses?
Because the heater matrix is part of the cooling system. The manual states it in three lines, the last of them in capitals: “there is no heater valve on the matrix. The coolant circulates permanently in the matrix, which contributes to cooling the engine. DO NOT CLAMP THE PIPES”. Clamping them to work on a hose, or fitting a shut-off tap “to stop the heating”, removes part of the cooling from a mid-engined car that already has its radiator at the far end of two long rigid pipes. The same page explains the bleeding that follows: unhook the expansion tank and hang it as high as possible, fill through it, open the two bleed screws — one on the thermostat housing, one on the front radiator — and close each as coolant comes out, level to MAXI, then run the engine at 1,500 rpm until the fans cut in. And a second prohibition: never open the bleed screws with the engine running. ⚠️ This is not an Alpine quirk: the Renault Safrane manual says it word for word — “there is no heater matrix valve. Circulation in the heater matrix is continuous, aiding engine cooling” — with the same ban on opening the bleed screws while the engine runs, and one instruction more: retighten the expansion bottle plug with the engine warm. It is a family rule, then, not a sports-car oddity. ⚠️ But not a rule of every era: the 1975 Renault 30, which has a heater tap and a conventional valved tank, does exactly the opposite — its manual says to run the engine for a few minutes after the thermostat opens, then open the bleed screws and close them as soon as coolant comes out in a steady jet free of bubbles. Each manual for ITS car: what is prescribed on an R30 is forbidden on a GTA. Alpine M.R.273, folio B-19 · Safrane M.R.302, chapter 19 · Renault 30 M.R.167, folio B-61.

In the Library

The workshop manual in three excerpts, the two period sheets and the network magazine, readable page by page: M.R.273 — V6 GT, engine · M.R.273 — V6 GT, ignition · M.R.273 — V6 Turbo, D501 update, injection · V6 GT (Z6W-A-700) — Pub et Trade sheet · V6 GT Turbo (Z7U-730) — Pub et Trade sheet · élan no. 77 (February 1985) — the Alpine PRV engines

On the forum

The GTA has its own section on the forum — presentations, restorations, questions to members who drive one. Alpine GTA section →

The codes behind the GTA

Z6W-A on the Z7W file, Z7U 730 on the Z7U file — and the catalysed GTA Le Mans.

Z7W file →Z7U file →GTA Le Mans file → All vehicles →