Hi Phil,

The B234F is a 16-valve DOHC B230 red block and uses the same LH 2.4 injection system. I had one in my 740 and really liked it. A smooth and powerful engine, at 155 HP it puts out almost as much as the B230FT turbo at 165 HP. The B234F first appeared in the 1988 740 GLE in Europe then in 1989 in North America. It carried on a couple of more years in the 740 GLE before being switched to the first of the new 940 series as the 940 GLE model in 1991/92 only, which was pretty much the end for that engine.

On the plus side there's no turbo lag, but on the minus side the torque curve is notably skewed to the right. To deal with that they re-geared the AW71 trans and gave it a lockup torque converter as the AW72L. Lockup worked really well with that engine as a "5th" gear that still had moderate power for passing at freeway speeds while providing extra fuel economy. The AW72L gear ratios still left a lot to be desired, which is why many preferred the optional M47 5-speed manual trans with the B234F (very few were made).

The revamped '89 740 GLE ran into production delays at the Halifax plant getting the B234F engines from Sweden, so the first ones didn't hit the show rooms in North American until January 1990 (dubbed 1989-1/2 models). I was in the market for a new Volvo at the time to replace the '74 144GL I'd had since new (it was getting a bit long in the tooth for use as a young business executive). After checking the early reviews and doing a test run, comparing it to a turbo, I decided to buy the 16-valve. The dealer wouldn't sell the showroom model (there were only one or two in Western Canada at the time), so I had to order mine. Halifax production was just starting to catch up and I didn't receive mine for another two months in mid-April.

Volvo also produced a 2 litre B204F 16-valve for the European market (to avoid a Euro surtax on larger engines) with a respectable 139 HP. Staying within the 2 litre surtax limit, they were able to add a turbo as an option for even more power (to compete with the likes of sporty BMWs) as the B204FT, which produced an impressive 190 HP. That turbo, which was mostly just sold in Italy, was much sought after by B234F types as it can be easily retrofitted to a B234F to produce well over 200 HP!! (unofficially, I've seen it said as high as 300 HP, but I'd guess closer to 230HP with stock wastegate adjustments). Compare that to a 240/700/900 B230F with a mere 116 HP! Unfortunately, production was low and those turbos were always as scarce as hens teeth and as good as impossible to find now.

The B234F is more fuel efficient than a B230FT, which is why Volvo wanted to introduced it. Unfortunately, it quickly gained a reputation as an unreliable engine, leastwise by Volvo standards, so Volvo soon backed off and stayed with the B230FT and their inline front wheel drive engines. The B234F's biggest issue is that it's an interference engine, so if the timing belt ever breaks you're looking at bent valves, and if it breaks at speed you can be looking at damaged valve seats and even damaged pistons. Worse still, the early B234Fs (to 1990) had a number of timing belt mechanism design flaws that could lead to even more broken belts (tensioner adjustment, oil pump pulley and balance belt drive pulley). Good 16-valve heads are next to impossible to find now, which doomed many of these cars to an early trip to the grave yard. It also has a serpentine belt for the twin balance shafts (to reduce harmonic vibrations) and if that ever breaks it normally takes out the main timing belt as well, so again a head crash. Both belts require special procedures for installation and adjustment (which is why I wrote the FAQ feature article that many consider the DIY bible on B234F timing belt replacement).
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now