VOLVO B234 - 16 VALVE HEAD Information + Pictures - by Anthony Hyde - Updated Jan 2015
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B234 F/G DOHC head - source, normally aspirated 740GLE. The 16V engine was also termed the 8 + 8 in sales brochures

Valve face diameter - Intake 34.5 mm, Exhaust 31.5 mm (8 off each) (by comparison an 8V SOHC intake is 44mm, exhaust 35mm (4 off each) Valve angle is inclined 20 degrees from horizontal.
Intake 34.5 mm #1317793 - Exhaust 31.5 mm #1317792
Original compression ratio 10.0:1 (needs to be reduced for turbo engines)
The B234 uses hydraulic lifters, no more shims, but expensive to replace. The B230 and B234 use the same head gasket.

Piston pic 1shows relief for valve tip clearance. Custom JE.

<-Click to enlarge

More JE piston pics
Piston 2
Side View
Piston 3
Underside View

For those seeking more performance from their current
8V turbo engine, a cheaper realistic alternative is to enhance the existing head & cam for more power.

Building up a more powerful 2.3 litre 4 cylinder turbo engine is an alluring thought. Good news is the 8V head can be replaced by a free flowing 16V normally aspirated B234 double overhead cam (DOHC) head that will bolt onto the red B230 ET/FT turbo block.

Volvo didn't combine a 16V head with a modern 2.3 litre B230 Turbo block, probably due to high cost, however, a 16V head can be sourced from a production non-turbo Volvo B234 engine, or from a few Volvo Penta marine engines particularly the sterndrives eg AQ171C = ....532 head casting number.
History wise, between 1989-94 Volvo did manufacture
in limited numbers two red 'B' turbo engines of 2.0 litre capacity, being a 16V 2.0L B204FT unleaded for eg. Italian and French markets, and a leaded fuel version; B204GT model with lambdasond for other markets. Both had 8.2:1 compression ratio. These engines are not readily obtainable secondhand. Neither engine was sold in Sweden.

Desirable performance 16V conversions are not straight forward, and may require additional components such as custom pistons to lower compression or use modified B230FT units (see pic of valve relief in B230 style dished pistons), programmable engine management, turbo exhaust manifold, hi-flow turbocharger, hi-flow injectors, B234 camshafts x2 or custom camshafts, adjustable timing gears x2, timing belt and tensioner, labor costs for engine building, reconditioning, assembly costs plus gaskets, etc. On RH (right hand drive) 740's it can be done but RH drive 240's don't really have enough engine bay room. Serious commitment and money are required to complete related project issues, but it can and has been done.
If using a B230FT block you will need advice on
Timing Belt and Tensioner ->Sales info

For a successful conversion, the starting point is seeking out a non-turbo 740/940 GLE (Sweden 740GLT) with a 16V head. With a second hand head/engine, beware of bent valves or broken cam carriers - a sign of belt breakage (typical comment - I have the head off now and at least 12 of the 16 valves are bent, so the head will be going to the machine shop), note the B234 is an interference engine, so be buyer wise. Replacement components (new) are typically sold in sets and are expensive. Remember to obtain all related components such as sensors, (some) wiring, inlet manifold, cams, ignition distributor, brackets etc.

The correct choice of a mating engine block is most important to avoid longer term problems. A 1995-on B230FT turbo block is the ultimate match. However, a 1991-on B230FT turbo block will suffice. From 1993, blocks featured oil squirters for piston cooling. 1991-on engines feature bigger main bearings, a relocated axial thrust bearing, stronger conrods and stiffer blocks. Recent advice is the normally aspirated B234 engine blocks is also suitable, a drawback being it doesn't have a turbo oil drain hole.
All red B230 blocks feature an internal oil pump. The B234 block/engine has an external belt driven oil pump. Recent advice is the external pump supplies a larger volume of oil for items like hydraulic lifters, dual cams and dual balance shaft lubrication, items not found on B230 ET/FT.

If using a B234 block for high performance purposes, people recommend removing the balance shafts (Link for more info). Link for Cam and timing belt information. Additionally for high performance, hydraulic lifters should be replaced with solid lifters.

Ash Davies contributes: Ignition Distributor - If planning to use a block-mounted distributor like any B2xx engine in a 240, this will interfere with the head. Answer is shorter distributor body, ie. Have the body machined down and a shorter shaft to clear the head. I have read that a shorter cap is available (ask SAM) in Sweden to resolve the issue. The alternative to these issues is an aftermarket engine management system setup that doesn't use a ign distributor for hall trigger signals and/or distributing spark, but instead uses a crank position toothed wheel (plus 2 sensors) and four direct firing coils.
Clutch master cylinder - (R-H Drive hydraulic) Clearance between the head and the clutch master cylinder will be tight at the very least. You may get around this by way of a cable-operated clutch or an alternative positioned clutch master cylinder.

Further Information - 16V advice by Pacman in Sweden

Comparison of VOLVO normally aspirated vs turbo 8V & 16V engines.




8V NON Turbo B230FB 1991 - 2.3 litre 9.8:1 CR

131 bhp ( 96kW) @ 5,500 rpm (USA B230F 116 bhp)

190Nm / 3,300 rpm (USA B230F 183 Nm @ 2,520 rpm)

8V Turbo B230FT 1991 - 2.3 litre 8.7:1 CR

165 bhp (121 kW) @ 4,800 rpm

264 Nm @ 3,450 rpm

16V NON Turbo B234F 1991 - 2.3 litre 10.0:1 CR

155 bhp (114 kW) @ 5,600 rpm

204 Nm @ 4,800 rpm - [little torque down low, flys at higher rpm]

16V Turbo B204FT 1991 - 2 litre 8.2:1 CR

190bhp (147 kW) @ 5,300 rpm

280 Nm @ 2,950 rpm

850 16V Turbo B5234 T 1994 - 2.3 litre 8.5:1 CR - 5 cylinder

225bhp (166 kW) @ 5,280 rpm

300 Nm @ 5,280 rpm

Comparison of SAAB turbo 8V & 16V engines. The 16V figures probably reflect an engine generation and engine management improvement but a useful comparison between heads all the same. The 1991-on Saab used a Trionic 32-bit MPU - Applicable Saab 16V T models: 9-5 Aero, Viggen.




8V Turbo 2.0 litre, 8.5:1 CR

135-145 bhp (107 kW) @ 5,000 rpm

235 Nm @ 3,000 rpm

16V Turbo 2.0 litre, 9.0:1 CR

165-185 bhp (173hp or 129kW)@ 5,300 rpm

273 Nm @ 3,000 rpm, Year 1988

16V Turbo 2.3 litre, 9.0:1 CR

200-230 bhp @ 5,500 rpm

258 Nm @ 2,500-4,500 rpm

16V B234 engine (non turbo)
- Click image to enlarge.
- note the 2x balance shafts (a Mitsubishi patent).
Bram Smits writes: Maintenance is a bit more than on an 8-valve, there's 2 belts and 5 tensioner/idler pulleys. Check them all, and replace as necessary.Yes, that's a lot of money in idler pulleys, and from experience I can say that these are parts where you really want the original Volvo-blessed parts.

B23 16V

HISTORIC PHOTO - 1981 - R-Sport 16V head # 1253264 plus #1253271

1981 Photo & artricle from Motor Manual (Australia). (article located by Warner Bowles, Sydney)

Volvo's competition department in Sweden (R-Sport) have developed this 2.3 litre DOHC 16 valve motor, based on the production B19 four cylinder block.

It develops 170 kW (228 hp) at 7,200 rpm fed by two 48 mm Solex twin choke ADDHE carburettors.
Thats a lot of power for a non turbo engine!

The motor is intended for use in rallycross competition. (for the Volvo 240 and 360)

In 1982 you could buy a full-house 16 Valve B21/23 conversion for 4000 UK Pounds (that's a real lot of money) from the R-Sport division of Volvo. Info from "The Story of Volvo Cars" by Graham Robson

Click to enlarge
1980 era. Carbs are Solex 48 ADDHE. Used in 343 and 240 rally cars

Link to Page 2 - Five delicious 16V engine conversion pics

Link to Page 3 - Custom fabricated Turbo Exhaust Manifold for 16V Head

Page 3 Includes Volvo 16V Turbo manifold part numbers, plus pics of 8V Turbo headers

Knowledge link Volvo B234F Head Conversion for 2.3L OHC Ford

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