Boxster S tuning

[JFP in PA]

Originally Posted by stilov

I'm sorry, one anecdotal experience of someone I have no knowledge of and hearing second hand does not justify saying tunes don't make much difference.

Obviously every car and every tuner (meaning person who writes programming, not some generic flasher product) are different.

A tune is also related to what changes someone makes on a car. In fact many rewrites of programs are required on many modifications. Ex. You can't run different fuel systems, different turbos, different cams without programming.

A lot depends on a ecu's range of values whether it can compensate adequately for a given modification.

As I see, a nearly stock boxster with minor bolt ons does not benefit much from tuning.

My other porsche would not run without reprogramming.

I have built several vehicles in which the "flash" as you call it made drastic differences and I have had cars that the benefit was non existent. (My e39 m5 for example)

What you think of my background is irrelevant; do a search, here and on other sites, ask some major league engine builders; we have run them on the track and on the dyno, they don't do much. These are Porsches, not Corvettes or BMW's; they have pretty unique programming in their DME, and are fairly well tuned as delivered from the factory. End of story....................

Go spend you money how ever you want.

[stilov]

Originally Posted by JFP in PA

What you think of my background is irrelevant; do a search, here and on other sites, ask some major league engine builders; we have run them on the track and on the dyno, they don't do much. These are Porsches, not Corvettes or BMW's; they have pretty unique programming in their DME, and are fairly well tuned as delivered from the factory. End of story....................

Go spend you money how ever you want.

I'm sorry, by no means did I intend for this thread to become adversarial and I did not mean to insinuate anything about your background.

I think maybe I came across in the original post as a newbie regarding modifications, wherein I can see why you feel the way you do.

I am however completely aware of the marketing hype that is involved in many (not all) claims as to power increases.

The original post was more to understand where a boxster lies as far as tuning. As you have said and others, it is pretty well tuned from the factory and seems to be able to do well with minor bolt ons.

However I stand by the fact that a general broad statement is similar to a stereotype and there are in fact cases in the car modifying world where alterations in tuning capabilities are required.

I am afraid my justification for that argument was construed as a pissing match..

I apologize for that, and again thank you for your comments.

[mmporsche]

Good information

[edc]

Here's what I did:

Tuned/modified 2000 Boxster S

[cheetah]

"Tuning" is really a vague term that might be causing some of the confusion here.

NA Boxsters with no or little mods will probably not see a big difference in power from a "tune". These engines already constantly monitor and change intake cam timing, have a type of variable intake tube length, and in later years change valve lift. NA car tunes usually bump timing up in places, remove speed limiters, turn on fans sooner, change WOT mode triggers, throttle response on e-throttle, etc. If done correctly, these can make the engine feel more responsive, if not necessarily faster.

Forced induction engines (Porsche or otherwise) can see a huge difference in HP along with the aforementioned improvements. Higher boost levels, less bleed-off, injector upsizing, and higher timing charts specifically for higher octane, all can support much higher power numbers.

Where tuning really takes off is when it is done for that specific vehicle over a period of time (not just on a dyno for 5 minutes). My previous daily driver was a 2000 Grand Prix GTP. Supercharged 3.8L V6 with an automatic. Stock was 240 hp, maybe 280 ft/lbs. I had the basic mods on it (smaller pulley, CAI, DP back exhaust, UP) and saw nice increases. But it was not until I starting custom tuning it that it woke up. I used HPTuners for that car and over a month period, made the car feel completely different. Having a permanent wideband and gauge installed, along with mini laptop plugged in and constantly logging allowed me to set up multiple histograms to chart and record all sorts of data and filter it out at my desk. Dialing in all my sensors one by one, getting all my long term fuel curves to be within 1.5% everywhere, experimenting with WOT triggers, removing the electronic bleed, adjusting WOT a/f ratios, and adjusting ignition timing for optimal power without knocking all were done without a dyno. The car became so "tuned" that I could unplug the regular O2 sensor and drive normally and stay near 14.7:1 without the correction from that sensor (verified with the wideband).

Dyno only testing is not preferred if possible and many cars base the WOT numbers off of where the car enters WOT. It locks in values and adjusts off of that point. It the regular closed loop values are off, the WOT values will be also.

Being an automatic, shift speeds, delays, and line pressure were all adjustable. Torque abuse modes altered also further helped my times.

While obviously a different beast than the Boxster, many of these same ideas and inputs are used in the OEM tune of each car. I wish that I had the ability to get into and adjust my tune as completely as I could with the Grand Prix. Softronic did a great tune for me without physically having my car, but I know that given time, I could tweak it more.

Until my Boxsters engine swap, my Grand Prix was as fast and quick as my Boxster until over 110 mph. The tune alone gave me 4-5 tenths on the 1/4 mile track. That is very significant! During everyday driving, it also increased my gas mileage. While every car is different, this goes to show how much a proper tune can gain someone.

Once I do not have to emissions test the Boxster (after a certain year), I will probably go the complete standalone route for the engine itself. Real time logic programming / logging will get the full potential out of my 3.4L.

While many of these online tunes might be a waste of money, a tune done right can be the best modification done to an engine.