Whether you have the 201HP base ’97 Boxster or the 295HP ’07 Boxster S, you frequently hear that the car isn’t fast enough, the owner wants to make it faster. You see ads promising an easy path to more horsepower … up to 425 … up to 450 …
So what can you do to a Boxster to make it faster?
- Reprogram the Engine Control Unit to match any mods you make.
- Install a bigger engine (3.2, 3.4, 3.6 or 3.8 litre)
- Bore the block out , re-sleeve it, and install new pistons to increase displacement or stroke it to do the same.
- SuperCharge it
- TurboCharge it.
- Increase the air flow into the engine by removing any restrictions.
- Increase the air flow into the engine by decreasing the resistance provided by the air cleaner.
- Increase the ability of the engine to exhaust gases by:
- Installing headers that are shaped differently or are of a different diameter.
- Removing one of the catalytic converters, replacing the remaining one with a less restrictive cat.
- Installing a less restrictive exhaust system
- Perhaps one which opens up more the higher the revs climb.
- Reprogram the Engine Control Unit to match any mods you make.
- Install a bigger engine (3.2, 3.4, 3.6 or 3.8 litre)
- Bore the block out , re-sleeve it, and install new pistons to increase displacement.
- SuperCharge it
- TurboCharge it.
- Increase the air flow into the engine by removing any restrictions.
- Increase the air flow into the engine by decreasing the resistance provided by the air cleaner.
- Increase the ability of the engine to exhaust gases by:
- Installing headers that are shaped differently or are of a different larger diameter. Ask if the headers are more or less effective at specific RPMs as the tuning of the intake and exhaust systems should match for best performance. You could end up with a system that hurts you in the lower RPMs while helping in the upper ranges.
- Removing one of the catalytic converters.
- Installing a less restrictive exhaust system
Warnings
These ideas are bad for your wallet! Someone who did many of the above (all but 2 and 4) estimated it cost him $51k and around $200 per HP!!
TINSTAAFL (There is no such thing as a free lunch.)
If more HP or Torque were that easy, the engineers at Porsche would probably be using the technique already (subject to the marketing strategy of keeping the Boxster/Cayman having less HP than the 911 variants and keeping the base Boxster less than the S).
And some of these may be bad for the long term health of your engine. Or result in a car that is less street-driveable.
Any of them will/may void any Porsche warranty (8.3 won’t if you use the Porsche Sports Exhaust PSE)).
Many of the claims of the sellers of these products are not backed up by any evidence or the evidence is fraudulent. If it sounds too good, it probably isn’t.
So lets discuss these modifications one at a time.
These comments are one man’s opinion. Ask on many of the online Boxster forums like PPBB or Renntech. There are people there who have done each of these mods and they have opinions and facts to supply to help you decide. You’ll have to sort out the “justify my decision BS” from the “facts” yourself.
The “cost” assume you had the item professionally installed unless it is an easy do-it-yourself install of less than 1 hour.
Generally involves taking the car to a shop that specializes in modifications and allowing them to install a new chip that is customized to the profile of the car as it exists at the time the shop is reprogramming it.
Beware of cheap chips that claim to be owner installable as they aren’t going to be customized for your car with the options you have installed on your car and proved by a dyno test on your car. And those are the only kind worth anything.
Recently, there have begun to be advertisements of what are known as Speed Mod Chips. They claim to boost HP by 10-20 and not void any warranty. And cost only ~$75. WRONG
These aren't "chips" at all, only a resistor. Many of these "chips" are plugged into the IAT, or Intake Air Temperature Sensor connector. The IAT is a Thermistor that changes a reference voltage to the engine's computer. This voltage is translated onto a "temperature" and the computer will increase or decrease fuel delivery according to this temperature. Cold air is more dense and requires more fuel, hot air requires the opposite.
This "chip" fools the computer into thinking the intake air is colder than it really is and consequently feeds more fuel into the combustion chamber. While many sellers state that the chip keeps fuel delivery within a certain "curve", this information means nothing. The modification essentially forces the engine to run rich all the time. The idea is more fuel equals more power. Unfortunately, rich running conditions will actually rob the engine of power, as the air/fuel ratio is far from ideal and will make combustion more difficult.
Today's computer controlled engines rely on a battery of sensors to help it run properly. If one sensor does not operate properly, the "runability" of the engine is adversely affected. In the case of a constant rich condition, the oxygen sensors will recognize that there is unburned fuel in the exhaust (due to poor combustion from the bad air/fuel ratio). They will command the engine to run lean in an attempt to correct the condition. (if the mod chip doesn't cause the engine to run OVERLY rich, the computer can negate all effects of the "chip" by LEANING the fuel ratio, making the mod useless!). If the rich condition cannot be corrected by leaning the ratio, guess what? You get a big, fat CHECK ENGINE light! (They claim the mod won't trigger that, either!) And if your vehicle is under warranty and the dealership finds that stupid little resistor where your IAT should be connected, you can KISS YOUR WARRANTY GOOD-BYE!
If your vehicle is out of warranty and you ignore the light, more severe damage can occur. The catalytic converter cannot cope with excessive amounts of unburned fuel and after a while of running rich and dumping raw fuel into the catalyst, the converter will be permanently damaged. Raw fuel and poor combustion will also foul the plugs and foul plugs have high resistance. High resistance can damage the ignition system! Lastly, raw fuel can wash down and glaze the cylinders, and it can wash out the oil ring on the piston which will negatively affect piston lubrication and will cost compression.
The bottom line is this: The "mod chips" DO NOT boost horsepower - the graphs they show are fake. They DO set the Check Engine Light. They DO void the manufacturer's warranty. And they CAN cause severe engine damage. Anybody considering this cheap performance enhancing option should think again and invest in a real, professionally programmed performance enhancing chip that REALLY adjusts fuel and timing curves. These pro chips cost more money for a reason: they work. These cheap eBay "mod chips" DO NOT.
Good programming isn’t cheap. Few things done right are. Use a shop that has done Boxsters before, who will customize the chip to your exact car with its mods/options and who will dyno test before and after and show you the results of the re-programming on YOUR car..
Cost: ~$???
Results: Generally affects the top end performance of the car, the rev limits, the optimum fuel/air mixtures. Generally doesn’t affect the performance in normal street driving. Sometimes makes other mods more driveable.
Names: www.GIACusa.com, www.revotechnik.com, Autothority, www.powerchipgroup.com, www.upsolute.com
Do-It-Yourself: Some
Best done by a shop that specializes in this sort of modification and has done several before yours. Too many of these result in failed attempts and end up as baskets of parts instead of as satisfying-to-drive cars.
A new from Porsche engine will cost more than one from a dismanteler but will come with all new accessories (alternator, starter, power steering pump, etc), all the updates that Porsche has added in 6+ years of production (like the new RMS!) and a 2 year warranty.
When you upgrade the engine, be sure to add the center radiator (and perhaps bumper) from an S model for the additional cooling. It is present on all the larger engined Porsche's for a reason.
Cost: $12k-$25k depending on the donor engine chosen, the source of the engine (new or used), the shop that does it and the other mods or repairs necessary.
Result: A driveable car with up to 400HP. Maintainable. Recommended.
Names: RUF, Sportec, FvD, Farnbacher Loles, 9ff, Orton
Issues are that Porsche has 2 kinds of control systems (non e-gas and e-gas) for their water cooled flat-6 engines. And converting between the two can be difficult and expensive. Which is why early Boxster non e-gas engine swaps are usually based on early non e-gas 996 3.4 engines.
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From the Softronic web site: "Softronic
makes full install kits to convert a wide variety of Porsche cars.
These kits include all hoses, mounts,gaskets ,DME programming and
required technical information for a complete install. All Softronics
conversions are guaranteed to produce full power as specified by
Porsche for such said engine. The converted cars are also fully
emissions compliant in all states. Softronic offers conversion's that
Porsche could have done yet did not., such as a 3.8S ,X51 or GT3 engine
in either a Cayman or Boxster." www.boxsterconversion.com for more information
Or increase stroke, new pistons, new camshaft, re-program ECU (TechArt to boost 3.4 Cayman to 3.8)
Cost: ~$4k-$30k
Results: Only heard of one 2.7 to 3.0 car this was done to and it was being sold. Don’t know what that tells you.
Names: www.imagineauto.com
Do-It-Yourself: I doubt it.
Cost: $3-4k
Results:
Name: www.tpcracing.net
Do-It-Yourself: No
Cost: $3-4k
Name: www.TurboKraft.com
Do-It-Yourself: No
Cost: $0 to $600
Result: More noise, more risk. A little less restriction. The Porsche engineers say the engine airflow is not limited by the intake.
Do-It-Yourself: Yes
The filter is most often one with larger holes that you coat with a thin film of oil to help trap the particles. You must be very careful with how much oil you use as the Mass Air Flow Sensor (MAF) is downstream of the air filter and the oil film can contaminate the MAF causing a Check Engine Light (CEL) and a poorly running engine until the MAF is cleaned or replaced ($350 list part).
Cost: ~$80-$580.
Do-It-Yourself: Yes
Cost:$1300-$3000
Name: Schnell, www.scargoracing.com, www.imagineauto.com
Do-It-Yourself: No
Cost: $???
Result: Less restrictive exhaust. Emissions issues?
Do-It-Yourself: Yes
Some of these mufflers have a loud sound but a resonance at certain critical RPMs that is unacceptable to some ears. Listen to one that someone else has, even drive in the car before you buy a muffler. You see lots of used mufflers for sale on eBay because people grew tired of them (or are turning a leased car in that they had the muffler installed on).
Cost: ~$500-$2000 depending on brand.
Result: Less back pressure, louder & deeper tone. Resonance? Ear damage over time.
Do-It-Yourself: Yes
Names: Porsche PSE, Gembella, RUF, Borla, Dansk, www.fabspeed.com, www.cargraphic.com, www.bbexhaust.com (Billy Boat), tubi, Remus, www.fvd.us, www.cargraphic.com
9. Lighten the car and driver
Robert from Sacrament posted:
gt3 seats,-20lbs(-25lbs if your seats are electric)
New exhaust,-20lbs(-25lbs if you have the PSE)
Braille battery,-20lbs
Diet and exercise,-?lbs
Lose the spare tire,-25lbs
Carrera Light weight wheels,-?lbs(I lost -30lbs when I swapped them with my Technology wheels)
after this is all done the car is still driveable and will feel more nimble
Doing several of these things at once can reduce the cost (if you are having the parts professionally installed) or work (if you are doing it yourself).
Trading your current car in on a stock car with more HP may be a better economic move that trying to modify too much. And would result in a car that is engineered as opposed to added on to. And it would be maintainable and might even have a warranty.
Modifications seldom return 10% of what they cost at resale time and can make the car hard to resell.
Consider the need to upgrade the brakes, suspension and tires as you change the way the car accelerates. It could save your life and will result in a better balanced car.
How about improving the driver instead?
It is one thing to improve the performance of the car itself, but quite another to improve your own driving skills to the point where you can get 100% out of the car you have. Many Porsche clubs sponsor Driver Education days where you take your car to a race track and, after instruction sessions where you learn the track, the principles of driving fast safely, and the meanings of the flags and signals corner workers use, you go out on the track with an instructor who coaches you through the corners. Generally, during a day you will get several track sessions and several discussions with the instructor. The DE sessions are non-competitive and don't require all the safety equipment that open-track days require.
Once you have done a DE, you begin thinking about more track time. Now go looking for a helmet, roll-bar extensions, fire extinguisher, dedicated track wheels/tires and the like. Not to mention track ready brake pads, suspension modifications, etc. It can go on and on with you still learning and improving the car and driver even after years of doing this.
All this without trying to make the car go faster or louder in a straight line, but faster around a track and faster than you did it the last time.
It's not cheap once you get into serious race track time, but it sure is a lot of fun. And it makes you a better street driver too.
My feelings?
First let me say that my feelings on the subject of "hot rodding a Boxster" are less important that yours. It is your car and your $$$.
Having said that, I bought the Boxster for its handling and balance, not for raw acceleration. I could have bought a more powerful Porsche or a car with twice as much horsepower. But either would have the potential for getting me in more trouble quicker and add little to the enjoyment I already feel when cruising with the top down or bending through the twisties. I don’t track or autocross.
Still I enjoy hearing about the modifications that are done by those that have the $$ and the inclination. Good luck in your project.