Continuing from part I, today I have a few more of the ways that you can increase horsepower in your car without being subject to the gimmick tax. In other words, these are the tried and true methods that work every time. If it's not on this list (or the list in Part I), it probably isn't a great investment of hard earned dollars.
Fitting a supercharger or turbocharger will always net a huge improvement in power production. Truthfully, of all modifications, this is the only one that can take a stock engineed car to another world of performance. While all motor modifications can net a healthy 10-20% gain over factory in a street car, turbocharger applications and superchargers as well both start well over 30% and climb to 100-200% with minimal effort.
While we're talking about forced induction, what's so wrong with nitrous oxide? It is a horribly exaggerated myth that nitrous damages engines. Nitrous doesn't kill engines, people kill engines. Nitrous is a great way to bolt-on 50 horsepower or so. You can do a lot more, but, getting greedy without supporting modifications is how nitrous use can go wrong. A 10lb bottle of nitrous jetted at 55 horsepower will last a very good while (after the first bottle when it's new to you) and frankly, nothing gives you instant POWER like nitrous. Second hand kits are very inexpensive, refills are cheap, and you pretty much can bolt-on 55-75 horsepower on any car with minimum trouble. However, if you want 100-150 hp, you really ought to look more towards turbo/supercharger applications, and for track days (road racing) you'll want to avoid nitrous. Nitrous is best for drag racing, and daily drivers where occasional blasts of power are desirable.
Tuning the air/fuel ratio, ignition timing, and cam timing can all either produce more power or give more power at the intended operating speeds of the engine. You may not always be able to pick up huge numbers here, but you usually will. With forced induction it's a requirement, and with anything beyond a typical "i/h/e" daily driver, it's also required to get optimum performance. To learn more about the tuning process, what it is, what it isn't, how to go about it and so on, check out Engine Tuning Secrets.
Weight loss of any kind will always improve performance, as long as you don't offset the weight distribution of the car horribly. However, unlike engine performance modifications, weight loss touches everything (handling, grip, fuel economy, straight line acceleration, etc). Weight loss is also very predictable, a car that weighs 100lbs less will always perform 100lbs lighter. Performance modifications to the engine may perform better in certain conditions than others and so are less predictable. You also never really know what a single change to one system may do to the others with engine parts, whereas with weight, it's pretty dang easy to know what will happen.
Swapping the engine is ALWAYS a great idea as long as the engine is a direct replacement. The absolute best engine is a stock engine, as it has years of intensive research invested in it and it's designed for even the most extreme conditions. Therefore, anytime there is a factory optional engine (or one from a similar model) that can be swapped in, that's your best choice of all. This is one reason that Hondas were and continue to be popular, the ability to swap a 90hp Civic with a 200hp engine that's factory reliable is incredible and the cost-benefit is usually VERY attractive.If you're debating building up an engine versus doing a relatively straight forward swap, you should ALWAYS do the swap. The only time to avoid engine swaps are when they require heavy fabrication. For example, placing a V8 in a Honda is going to be extremely expensive and likely end in a comical but not terribly effective car. For Honda guys (Civic/Integra/Prelude/Accord/etc), I recommend you check out the Ultimate H22 Swap Guide for a great resource on swapping in one of the best affordable Honda engines around - the H22.
In a coming post, I'll be talking about suspension modifications that actually work (vs those that don't - which there are many more of those). Stay tuned.
Extremely Limited Time Offer - 3 Days Only
Get a MASTERS DEGREE in Performance Tuning from the BEST in the Field for ONE low package price
For 3 days only, get ALL of our PREMIUM (not available anywhere else) Tuner University Courses featuring some of the greatest minds in motorsports:
- Top 10 Performance Myths Class (MP3 and Edited Transcript) - $29.95 value
- Performance on a Sip of Fuel Class (MP3 and class manual) - $69.95 value
- Header Design Secrets with John Grudynski (MP3 and transcript) - $69.95 value
- Dirty Secrets of Oil with Ryan Stark (MP3 and transcript) - $69.95 value
- Engine Tuning Secrets with Ben Strader of EFI University (MP3 and Transcript) - $69.95 value
Get all of the above courses (many of which not currently available anywhere else) for one single price of just $309.75 $69.95. A HUGE package savings.
You can also buy any of these individually through our resource center, but I don't know why you would as this is basically the whole store for the price of just 1 course. You'll get the MP3 recordings of each class as well as a transcript or companion manual with each course and you'll be able to download them all INSTANTLY.