Engine Performance Upgrades for Vintage Volvos (1962-1975)
Every spring, we get calls from Vintage Volvo owners who are interested in increasing the horsepower in their trusty relicr.One of the more common questions is along the line of“how do I get more power out of my car without spending a fortune?”There isn’t an easy answer to this.
The first step is to move away from the “it’s still running so I’ll leave it alone” mindset.Before upgrading anything, it’s critical to ensure that you’re starting with a solid foundation.Many people have installed more aggressive cams, headers and large exhausts only to find that their Volvos don’t go any faster than they did before spending several hundred dollars.
For example, a performance oriented camshaft or exhaust header won’t do much good in an engine that’s losing compression past worn out rings.The first thing to do is avoid the temptation toward ‘bigger is better.’Instead, consider the kind of driving you’re actually going to be doing.How often do you really rev to 6000rpms?Do you use the car for carrying heavy loads, pulling a trailer or camping?Each of these factors plays a role.ipd offers a vairety of stock grind cams if you’re interested in returning a tired engine back to its original configuration.
However, if you’d like to increase the power output, we also offer the Street Torque and the Street Performance camshafts.The Street Torque is the more ‘civilized’ of the two and offers a strong powerband in the low and mid range rpms while the Street Performance is stronger in the higher revs.If you’re looking for still more power, consider an exhaust header and a larger diameter exhaust system.Think of your engine as an air pump: the more air you can move through the engine, the more horsepower it will provide (this is a rough analogy - it isn’t quite as simple as this).Like camshafts, exhaust components should be chosen with care.A little bit bigger can be a lot better but a lot bigger can be a lot worse.Pay no attention to those who claim that 3” exhausts will result in massive power increases - it’s basically true that as the exhaust diameter increases, high end horsepower will also increase.However, as the exhaust diameter increases, low end torque will decrease.This doesn’t matter if you have a race car with a power band that ranges from 4000 rpms to 8000rpms but makes for a very hard to drive car in real world traffic.And economy will suffer too.
We’ve found that either the Street Torque or the Street Performance cams, coupled with a header and a 2 inch exhaust system, work nicely on otherwise stock B20 engines.If you’re building a 2130cc big bore kit, you may find that 2.25” or even 2.5” is more suitable as the larger displacement will provide an increase in low end torque that more than compensates for the larger pipe diameter.Confusing?Yes.
Whether you’re beginning a complete engine rebuild or simply freshening up a worn engine, choosing the correct parts is critical - it’s easy to spend hundreds, even thousands of dollars on a perfectly balanced and expertly assembled engine that ends up offering less horsepower than a solid, stock B18 or B20.This is exactly what we’d like to avoid.If this opens up more questions than it answers, please give us a call at (800) 444-6473 and we’ll be happy to share what information we’ve managed to collect over the years in order to ensure that the next engine you build or refresh will yield the results you want.