Old Power StagesPOWER STAGES This is a list of naturally aspirated modifications that can be done to improve the power output of your car. They are organized into stages where initial modifications are the most effective for improving power early on and are needed to support the mods in higher stages. Mods generally get tougher as you go up in stages, but not always. Some easy to perform mods are in high stages since they have little or no effect until other mods are performed first. cost: Approximate price range (from cheapest to most expensive cost) of the modification, not including any labor charges for the installation. aprox. HP: Rough estimate of PEAK wheel HP gains with this mod, dependent upon supporting mods and other conditions, determined wherever possible by 2GNT members who have dynoed their cars before and after the modification was done. Estimates get less accurate for the highest stages. � mile improvement: Approx. improvement in � mile time with this mod, dependent upon weather conditions, tuning, supporting mods, driver experience, and other conditions. The estimate is determined by 2GNT members who have raced their cars at the drag strip before and after installing the modification (and ONLY that modification). difficulty: rating system from 1 to 5 for the difficulty of the installation 1. A drunken monkey could do this mod. 2. A bit more challenging but still very possible for a beginner, should not take very long. 3. Need some experience to perform this mod but it won't take too long, OR mod is very time consuming but not really difficult (just bolting and unbolting). In either case an extra hand would probably be a good idea. 4. Tough one to do yourself. You�ll most likely need someone to help out. You need to know what you are doing or you could mess stuff up, and it will take a very long to accomplish. 5. Take it to a shop unless you are an expert or have expert/experienced help. It will take forever to finish and you�ll need someone to help you. stage 1: exhaust cost $40-$600 difficulty 2 approx. wheel HP: 5 approx. � mile improvement: 0.1 to 0.15 sec comment: Essential to reduce restriction in exhaust. A muffler from a GS-T is the least expensive replacement and very effective, but a larger diameter cat back would be a better choice if you plan on extensive naturally aspirated modifications (i.e. stage 5-6) and essential if your long term plans are to buy a turbo or nitrous kit. intake cost $50-$250 difficulty 1 approx. wheel HP: 8-12 approx. � mile improvement: 0.15-0.3 sec comment: Replaces the extremely restrictive stock air box. Price, and power increase, ranges from a cone filter on the end of the stock intake tube, to short ram intakes, to a cold air setup. A cold air intake is easily the most effective intake to get, but be careful of ingesting water into the engine. You could, of course, build your own intake out of custom piping. stage 2: UDP cost $160-$200 difficulty 3 approx. wheel HP: 5-8 approx. � mile improvement: 0.1 sec comment: Reduces the drag of the accessories on the engine (A/C, power steering, alternator). Very effective modification that improves power over the entire RPM range. Header cost $200-$450 difficulty 2 approx. wheel HP: 1-2 at high RPMS, much more at low RPMS approx. � mile improvement: typically none comment: A header reduces some restriction in your exhaust path, but more importantly tunes your car�s exhaust to provide power at certain points in the RPM range. Typically a header does not add very much top end power to our cars and does little, if anything, for the � mile. But, a header is still an effective modification since it does add significant low end power which helps to greatly improve performance on the street. A header could prove more effective for drag racing and top end power with a VERY short runner design and with more extensive modifications. stage 3: intake manifold cost: $0-$450 difficulty: 3 for installation, 3 if you try to port it yourself, very time consuming to do yourself approx. wheel HP: 5-8 approx. � mile improvement: 0.1-0.15 sec comment: Intake manifold work improves airflow through our intake manifolds (which have very long runners with a sand cast finish), yielding more top end power. A port and polish job is typically much cheaper than a manifold that has been Extrude Honed and should give similar results, especially if you do it yourself. SAFC � Super Air Flow Converter Cost: $200-$310 Difficulty: 3 approx. wheel HP: 8 approx. � mile improvement: 0.15 sec comment: A SAFC will allow control of the air/fuel mixture. With proper tuning some significant gains can be made with a SAFC, but improper tuning can cause serious engine damage. A standalone computer at this point might be a better idea if you plan on some very SERIOUS modifications in the future. after market computer (instead of SAFC) � (typically an AFX race computer) Cost: $370-$500 Difficulty: 1 for plug and play computer approx. wheel HP: 10-15 approx. � mile improvement: 0.20 or possibly more comment: An after market computer will improve the car�s air/fuel mixture and ignition timing, improving power without the guesswork of tuning a SAFC. While it has the advantages of ease of installation and it does not need to be tuned (which is probably perfect for most people); certain applications might require the tuning ability of an SAFC. A standalone computer at this point might be a better idea if you plan on some very SERIOUS modifications in the future. Some specific valve train upgrades might be needed to handle repeated use at the higher than stock rev limiter provided by an aftermarket computer. stage 4: high flow catalytic converter or test pipe cost: $50-$200 difficulty: 2 approx. wheel HP: 2-5 approx. � mile improvement: 0.05-0.1 sec comment: Reduces (or removes completely) the restriction in the exhaust caused by the catalytic converter. Not a very effective modification if done before this stage. A test pipe is cheaper than a high flow cat and will give noticeably more power, but is illegal on the street. cam gears cost: $250-$300 difficulty: 4 approx. wheel HP: 6-8 approx. � mile improvement: 0.1 sec comment: Tuning of stock camshafts with adjustable cam gears can give a noticeable power increase, but needs to be tuned on a dyno to be most effective. The cam gears can actually be tuned to give you top end power or low end power. They are difficult to install, so make sure you know what you are doing before hand. They are essential later on if you are changing your camshafts to after market ones. throttle body cost: $0-$100 difficulty: 1, 5 if you bore it yourself approx. wheel HP: 5 approx. � mile improvement: 0.1 sec if used with a cold air intake and a ported/polished intake manifold comment: Reduces restriction caused by throttle body and increases power in the upper RPM range. It also greatly increases throttle response. Can be done much earlier than stage 4 if you desire more throttle response, but typically does not improve HP much until other supporting mods are in place. This is because improvements to other parts of your intake path earlier on are more effective, as the throttle body isn�t the major restriction in the intake path. stage 5: standalone computer cost: $1000-$2000 or more difficulty: 1 plug and play system, 4 wire in yourself approx. wheel HP: 15-20 or more, depending on other mods and tuning approx. � mile improvement: 0.25 sec possibly more comment: Used instead of a SAFC or an after market computer for ultimate control of the car�s fuel and timing maps. Must be tuned precisely and thoroughly to be effective or engine damage can occur. Essential for some turbo and nitrous applications, and for higher compression pistons, head work, race cams, and other extensive modifications. cam shafts cost: $200-$600 difficulty: 4 approx. wheel HP: 10-20, possibly more, depending on type of camshafts and other mods approx. � mile improvement: 0.20 seconds, possibly more comment: Changes the lift and duration of your camshaft timing. They are essential for gaining very serious amounts of power. A mild cam will not affect your low end much (if at all) and keep your car useable for the street, but will also not provide as much power. A race cam will kill your low end while providing lots of top end power, and most likely will require a standalone computer for an increased rev limiter, and an upgraded valve train to handle the higher lift and duration provided by race cams. Reground cams are also available and cheaper than regular aftermarket cams, but you will loose valve lift and need to shim the valves to regain it. plug wires cost: $50-$150 Difficulty: 1 approx. wheel HP: none, see below approx. � mile improvement: none, see below comment: Yes, plug wires are in stage 5. Why? Because unless your stock wires are going bad, after market wires are useless up until you actually need an upgraded ignition. (Save your money for something that actually provides HP!) They do NOT provide more HP, but are ESSENTIAL if you have after market coil packs and ignition amplifiers, which is why they are in the stage just before those modifications. stage 6: head work (includes valve train upgrades) cost: $660-$1600 difficulty 5 for install approx. wheel HP: possibly up to 50hp for the headwork in conjunction with a higher rev limiter and very high performance cams approx. � mile improvement: at least 0.40 seconds possibly more Comment: Getting your head worked on can range from just smoothing the ports and doing light bowl work (about $660) all the way up to full port work, valve job (3 or 5 angle at least), and valve train rebuild (new springs, lash adjusters, rocker arms, and oversized valves). Head work sometimes comes in packages with valve train upgrades included with it, but parts of the valve train can be replaced as needed. The valve train upgrades have been included with the headwork for the sake of simplicity. Valve train upgrades are usually done to allow the valve train to take greater stress. bottom end rebuild/stroker kit cost: $1100 bottom end rebuild, $1600 for 2.2L stroker kit with bottom end rebuild difficulty: 5 approx. wheel HP: Each point of compression adds 4% to your power. Stroker kit adds displacement, which should add about 20 HP or so. Approx. � mile improvement: 0.30-0.40 seconds, possibly more Comment: A bottom end rebuild will replace your pistons, connecting rods, rings, and bearings. Increased compression will add 4% more power for each point above what you already have (i.e. going from 9.6 to 1 to 10.6 to 1 compression will add 4% more power, it�s in the textbook). Higher compression typically requires a stronger ignition system in order to work. A stroker kit adds displacement to your combustion chamber and more displacement means more potential for more power. Typically bottom end rebuilds are done with other supporting mods or for turbo kit applications. ignition amplifier cost: $320-$360 difficulty: 2 approx. wheel HP: none or very little, see below approx. � mile improvement: none see below Comment: Stronger ignition coils are typically required to work with very high HP applications (cams, headwork, and higher rev limiter) and higher compression ratio pistons. Might give you a little power at these higher power levels. Requires the use of two tach adapter to allow this to work with the 420a crank angle sensor. ignition retard cost: $100-$140 difficulty: 2 approx. wheel HP: none see below approx. � mile improvement: none see below Comment: Ignition retard is needed with very high compression to protect your car from detonation. Power_Stages |
| Document statistics: Last modified on 2006-08-08 19:25:29 by DR1665 |