The Guide for Volvo B20 Engine. Since it first appeared on the assembly line for the 1969 model year, Volvo’s B20 engine has earned a stellar reputation. The renowned Volvo B18 engine was replaced by the B20 Volvo, which was produced until the early 1980s. The B20 engine was available in six different variations from Volvo, including fuel-injected and single- and double-carburetor models.
Although the B20 is less well-known to newer generations, for many years it was a top-performing engine. Although it has not been produced since the 1980s, it is still seen today in innumerable Volvos, both in automobiles and howitzers for the Indian military (seriously). We’ll discuss the Volvo B20’s specifications, background, dependability, and performance in this manual.
Technical specifications for the Volvo B20
Vehicle Uses for Volvo B20
- Volvo 120 Series, 1969–1970 (Amazon) (including 123GT)
- Volvo 140 Series, 1969–1974
- Volvo GTZ, 1969 (Concept car)
- Volvo P1800/S/E/ES, 1969–1973.
- Volvo 200 Series, 1974–1976
Some non-vehicle uses were also powered by the Volvo B20:
- Volvo Bandvagn 202/203 (Mk. II) from 1969 to 1981 (All-Terrain Military Vehicle)
- Volvo Laplander C202, 1977–1981. (All-Terrain Military Vehicle)
- Howitzer Bofors Haubits FH77/A
History of the B18 Volvo Engine
The original Volvo B-Series engines
The B4B was the first engine of the B-series, and Volvo started making it in 1944, towards the end of World War II. Volvo’s B4B was a pushrod, 1.4 L single-carbureted inline-four engine; the B14 was a double-carbureted variant. Volvo expanded the B4B/B14 to 1.6 L in 1956, resulting in the B16 for 1957.
The B16 was installed in the PV544, the successor to the original Volvo PV444 that was powered by the B4B. In the late 1950s, Volvo installed the B14 and B16 in the initial P1900 Roadsters. Depending on the year and model it was in, the B14/B16 only had a rating of 50–70 horsepower.
Volvo bored out the B-series once more in 1962, this time in the B18 to 1.8 L. The Marcos 1800 GT, Facel III, and 123GT were among the famous vehicles powered by the B18, which had a horsepower range of 75 to 115. One of the most dependable motors ever made is the B18. One guy with a Volvo P1800S was able to get more than 3 million, yes, million, miles out of his B18.
The B20 to the Volvo B18
Volvo developed the 2.0 L B20 engine in 1969 by thirdly boring out the B-series. In most applications, the B20 Volvo instantly replaced the B18 thanks to its increased horsepower and torque. With respectable gains of 15 horsepower and 18 lb-ft of torque, Volvo rated the B20 between 90 and 130 horsepower and 101 and 130 lb-ft of torque.
Midway through the 1970s, Volvo phased out the B20 in automobiles after a comparatively brief run of manufacturing. However, it did show up in a number of vehicles, including the GTZ concept car, the 120 Series, the 140 Series, the 200 (240) Series, and P1800/S/E/ES. Only two of the GTZ’s intended three high-performance coupes were ever produced, one in 1969 and one in 1970. The B20 was used in the 1969 GTZ.
The somewhat bigger Volvo Redblock engine, also known as the B21, replaced the B20. The B21 was more than simply a bored-down version of the B20; it also had a unique valve train and a number of turbocharged models. By 1977, Volvo had stopped employing the B20 in their vehicles; the only usage that persisted were for military purposes.
Military Uses of the Volvo B20
The Laplander C202 and Bandvagn 202 are two vehicles that the Swedish military employed the B20 to replace the B18 in. The Bandvagn was only utilised by the military, whilst the C202 was designated as a civilian vehicle.
The B20 was used by the all-terrain transport Bandvagn 202 from 1969 to 1981. In addition to Sweden, B20-powered Bandvagn was also utilised in Canada, Finland, the Netherlands, Norway, and the United Kingdom. The Bandvagn has been used in environments ranging from the Middle Eastern desert to the Antarctic ice caps, demonstrating the engine’s remarkable engineering and versatility.
Even though it only has a 2.0 L engine, the Bandvagn can carry up to 10 troops in addition to a one-ton payload. Many of them are still in service today and have an estimated 97 horsepower in the Bandvagn.
The Haubits FH77/A Howitzer artillery gun’s auxiliary drive system was powered by the B20 manufactured by the manufacturer Bofor. The Volvo B20 in the FH77/A is coupled to hydraulic pumps that power the ammo crane, breech closure, auxiliary wheel, wheel motors, and wheel motors.
Fundamentals of B20 Volvo Engine Design
A 2.0 L inline-four engine with an overhead valve train powers the Volvo B20 (OHV). Each cylinder has two valves, for a total of eight valves. The 1.8 L B18 engine is a bored variant of the B20 Volvo, which has an 88.9 mm x 80 mm bore and stroke. Because it has a split bore centre, the space between the middle two cylinders, 2 and 3, is broader than it is between cylinders 1 and 2 or 3 and 4.
Both the firing sequence (1-3-4-2 anticlockwise) and the oil capacity (3.75 l) are identical to those of the B18. And kept the 12 volt electrical system from the B18, but now it used an alternator rather than a generator. Volvo provided Zenith/Stromberg or S.U. carburetors for select B20 models, while Bosch’s D-Jetronic or K-Jetronic fuel injection systems were used in other models.
Volvo produced numerous variations of the B20, similar to the B18. The B20 A-F come in a total of six variations.
Volvo used the B20A in the 145 express and 200 Series, as well as the 140 Series, 142 basic and deluxe models. It had an 8.7:1 compression ratio, a single Zenith/Stromberg carburetor, and was rated at 90 horsepower and 119 lb-ft of torque. The first B20 Volvo produced was the B20A.
A double-carburetor variant of the B20A Volvo is the B20B. Volvo reduced compression from 9.5:1 in 1969–1970 to 9.3:1 in 1971 and then further from 1972–1974 to 8.7:1. Volvo used the B20B in the 1800S and the 140 Series’ luxury variants. They estimated the B20B’s horsepower and torque to be between 97 and 118 and 103 and 123 lb-ft, respectively.
The 1800E and 140 Series Grand Luxe versions are just two of the models that Volvo equipped with the B20E. The Bosch D-Jetronic system was used by the Volvo B20E from 1970 to 1973, and the Bosch K-Jetronic system from 1974 to 1975. The Volvo B20E is a fuel-injected variation of the B20. The B20E featured a very high 10.5:1 compression ratio and produced 130 hp and 130 lb-ft of torque.
Volvo installed the B20F in the 1800ES, 140 Series, and 200 Series between 1972 and 1976. The Bosch D-Jetronic system was used by the B20F from 1972 to 1973, and the Bosch K-Jetronic system from 1974 to 1975. The B20F is a fuel-injected vehicle, just like the B20E. The Bosch B20F featured an 8.7:1 compression ratio and produced 94–112 horsepower as well as 105–115 lb-ft of torque.
The B20F was essentially a B20E with low compression. Volvo equipped the B20F with a catalytic converter in some models, however the carburetor was used in other B20F models to manage emissions.
Reliability of the Volvo B20
The B20 is still regarded as a very reliable engine, although not quite having the same 3 million mile motor reputation as its B18 forerunner. There are still several B20 power cars on the road today with 200,000 or more miles on them. In addition, the original Laplander and Bandvagn all-terrain vehicles are still in use by citizens and some militaries.
The B20 is practically indestructible for longevity in its basic configuration. It still has all the issues that a 40–50 year old engine would have, therefore all of the belts and hoses need to be carefully examined. The rear crank seal is known to periodically leak, and the timing gear teeth are also susceptible to breaking from continuous use.
Also, the breather gauzes and regulators for the carburetors both require maintenance. Volvo switched to the K-Jetronic system because the Bosch D-Jetronic system, which was the original, had issues.
Performance and Modifications of the Volvo B20
Despite what you may believe, many performance fans choose the Volvo B20 since it is an extremely modifiable vehicle. A Team Volvo dragster powered by a modified B20 engine was created in Norway and can run the quarter mile in under 9 seconds while travelling over 150 mph. It uses a powerful turbocharger to produce 40 PSI of boost to enable it complete the breath-taking dash.
Adding a turbocharger to the B20 is one of the most popular upgrades. For several of the slightly larger B21 series engines producing between 6 and 9 PSI of boost, Volvo used a Garret T3 turbo. Several people replace these turbos with other turbos that are T3 sized and run the same amount of boost.
You should probably begin turbocharging your B20 with one of the lower compression variants, such as the F or B, with the F being preferred because of the fuel injection. You should start with the K-Jetronic fuel injection system, though many people later upgrade to a Megasquirt system.
Here are two manuals (A and B) for rebuilding and restoring B20 engines. Remember that it will require a lot of work because the newest B20 motor you can find is still four decades away from manufacture. But if you can get through it, the outcome will be worth it in the end.
Volvo Legacy B20
One of the best Volvo engines ever made is the B20. It produced some highly iconic vintage coupes, sedans, and waggons between 1969 and 1981. Although it didn’t appear to be much, the powerful inline-four could travel for countless miles without experiencing any problems. Volvo employed the B20 in numerous automobile models, including the 140 Series, 200 Series, and 1800E, as well as in a number of military vehicles, including the Laplander L3314 and Bandvagn 202.
Like the engines themselves, maybe the spirit of the B20 Volvo will never die. They nevertheless have a large enthusiast community and reputation despite being out of formal manufacture for more than 40 years. Here’s to the legendary Volvo B20, an inline-four that will never be topped.