<img height="1" width="1" style="display:none" src="https://www.facebook.com/tr?id=918799731584652&amp;ev=PageView&amp;noscript=1">
FCP Euro Service Kits

FCP Euro Kits

A naturally aspirated engine is one that does not use any form of forced induction such as a turbocharger or supercharger. In the last few years, many car manufactures have been using turbochargers and superchargers (forced induction) due to their ability to make a smaller displacement engine more powerful and yield better fuel economy. There are advantages and disadvantages to using or not using forced induction.  I personally prefer a naturally aspirated engine for its linear power delivery (no lag!) and their characterful engine notes. (Think Porsche 911 GT3 or Lexus LFA).

Lexus LFA Source: autoblog.com

Cars like the LFA and 911 GT3 have all of the lovely naturally aspirated advantages as well as PLENTY of power to boot (553hp and 475hp, respectively).

The trouble is for many of us, the naturally aspirated version of our car, like my 1998 Volvo S70, happens to be the base model and generally is significantly down on power from its turbocharged brothers. The 1998 S70 N/A came stock with a 2.4L engine producing 168hp and 162lb-ft of torque. I love the character and sound of this engine, those numbers can be a little depressing when compared to the range topping T5 - a 2.3L Turbocharged engine with 237hp!

Source: autoblog.com Source: autoblog.com

While you may not be able to have the horsepower gains found from forced induction, there are a few things owners can do to get the most and maybe even a little more from their naturally aspirated engine without spending a ton of money. However, do know that if you really are looking for large power gains, you might want to consider selling your vehicle and buying something with forced induction. I was perfectly content knowing I may only get a few extra horsepower.

"Stage 0" Tune

To most people, this is just a complete tune up of their vehicle. On my Volvo S70 this consisted of doing: spark plugs, spark plug wires, distributor cap and rotor, air filter, fuel filter and an oil change. A stage 0 tune sets a baseline for your engines performance as it involves replacing a majority of the wear items in your engines direct line to making power. On newer cars you may also want to consider replacing the coil packs since most of them do not have a distributor. While this will not add power to your engine it will certainly help with its response especially if its been a few years since this has been done. FCP sells tune up kits for many vehicles. Before attempting to do anything else with your engine, do this first!

Air Intake & Exhaust Upgrades

There are really only two variable factors that come into play when trying to make more power from your naturally aspirated engine: air & fuel. Allowing the engine to breathe better is sure to add a bit more power to your engine.

open-uri20141028-15549-1g6lqxfChanging the stock air intake can help to allow a greater volume of air into your engine for combustion and can also give your vehicle a more tasteful intake noise. Companies like DINAN have designed cold air intakes for many different BMW models as BMW used their naturally aspirated Inline-6 cylinder throughout much of their earlier model ranges (E36 3-Series, E46 3-Series, E39 5-Series - to name a few).

I opted to leave my stock intake system in my Volvo and installed a K&N High-Flow Air Filter. K&N claims some ambitious power gains (+15hp in some applications). I found in practice that my car was a bit more responsive in low end, aggressive acceleration. K&N manufactures high flow air filters for virtually every manufacture and vehicle. They are also re-usable if maintained properly.

While a new exhaust system is on the pricier side of performance upgrades, they aid in allowing your engine to breathe better. An upgraded exhaust will have much larger diameter piping which will allow more air to leave the engine at any given time and also a less restrictive catalytic converter.

Using the correct octane fuel

This is something simple, though most owners do not realize they may be hindering their engine's performance by using the wrong gasoline specified by their vehicle for optimal performance. For the first few months of ownership, I ran my car on 87 grade gasoline. I thought that since it was not a turbo, premium gasoline was not necessary. When thumbing through my owners manual, curious about what the car requires, I read that Volvo recommends a minimum 91 grade for optimal performance. At my next fill-up, I used premium gasoline. While I did not notice any power difference, I did gain about 2MPG more from that tank. While 87 octane is the minimum grade required by Volvo, 91 grade did exhibit a noticeable benefit for me.

While many modern cars have ECUs which can compensate for the difference in fuel quality, the downside for your car could be its running down on power and you may not even know. Check your owners manual to see whats best for your vehicle.

open-uri20150310-5429-msjl7bECU Tunes/Flash

As discussed above, naturally aspirated engines have two main variables to them: air & fuel. The air to fuel mix ratio is determined by your cars computer or ECU. The manufacture generally opts for a more conservative set up from the factory. There are many different aftermarket companies which make brand and model specific ECU tunes for naturally aspirated cars. My Volvo uses a tune made by ARD which gave a modest gain of about 15hp but also a few more MPG on the highway. DINAN also offer ECU tunes for BMW's N/A models as well.

Suspension Upgrades

While these are in no way related to extracting more from your engine, a good sports suspension set up can allow you to use more of what you do have for power on the road. This is certainly a different way of looking at things, but with only a few elements to tune on these N/A cars, thinking outside the box is helpful! You can cover a twisty backroad using much more of the power you do have when you have a nice, tight, sporty suspension setup. A better suspension setup can inspire confidence to cover ground more quickly, increasing the overall performance of your vehicle...if that makes sense!

Bottom Line

I know what you're thinking: "Why spend money at all on these upgrades which wont even make my car as fast as its turbo equivalent?"

Consider this, your engine is perhaps one of the last of its kind. As stated above, more and more manufactures are moving to turbocharging, supercharging and even both in some applications. While these new engines are much more efficient and can produce more power, they can have awkward power bands, a less than desirable exhaust note, and, on older turbo cars, reliability issues (Think Audi's 2.7T engine). Attempting to tune a car like my S70 N/A must perhaps be rooted in a desire to preserve the bullet-proof reliable 2.4L B5244S as opposed to getting massive power gains.

Shop Volvo at FCP Euro

 


About the Author: Noah Jenkins

Noah_headshotNoah Jenkins is attending the University of Connecticut studying Electrical Engineering. He’s been around Volvos since birth and currently drives and maintains a 1998 S70. His knowledge and interest in European vehicles expands to BMW, Audi, and Land Rover as well.


author image
Written by :
Noah Jenkins

Noah Jenkins is attending the University of Connecticut studying Electrical Engineering. He’s been around Volvos since birth. His knowledge and interest in European vehicles expands to Audi, BMW and Land Rover as well. He currently drives and maintains a 2004 Audi A4 Avant and a 1996 Volvo 850


More Related Articles