i have a 90 Volvo 240 manual trans. Is there any gain to changing injectors to a modern injector with better and finer mist? Just curious Im going to pull mine and change out orings and clean. I would be willing to purchase some new ones if there is any gain? Thanks for the help and advice.

 

If yours are working fine, nope.

 

if the o-rings aren't leaking air (easily tested by blowing some non-oxygen gas like propane past them), and your engine is running fine, then there's no point in even touching them. we've got a 240 with a half million miles on its original injectors, never been touched.

 

no advantage. If you were upgrading the turbo then you can swap for injectors with more flow, but assuming you don't have any start up issues (suggesting a leaky injector) you should simply run a tank or two of premium gas or drop in an after market injector cleaner product every so often to get some extra detergent action to keep the injectors clean.

 

indeed, the B230FT turbo engines used on 740/940 turbos has higher flow rate injectors, and an ECU that know about them. these injectors also require a ballast resistor pack between the supply voltage and the injectors. Putting said injectors on a non-turbo would spray too much fuel, although the O2 sensor + ECU might have enough range to lean them back out again, net effect would be nil if it can lean it back out, or excess fuel consumption if it can't.