Performance upgrades ....

[Guest]

All Boxster people,

I require some advice. I have a 2003 MY 2.7 (228BHP) Boxster with 8k miles. What I'd like to do is add some more low-down torque, and some more BHP.

My ideas, so far, are;

* Chip conversion
* Exhaust upgrade.

Any ideas/experience on this matter would be extremely helpfull I live in the Thames Valley, so anywhere (fairly) local where these could get done would be a massive bonus.

Many thanks in advance, Simon.

 

[Guest]

Free flowing exhausts and racing cats can give more power, but this is all at the top end. Often it is at the expense of mid range torque, so I would avoid changing the exhaust.

To get more torque you need to get more fuel, which can be done by remapping it. Obviously it is limited by how much air can get in as well, so you might want to change the air filter, since more fuel is no use if there is no air to burn it with.

Ultimately though significantly more torque comes with either a bigger engine, or more air (through either a turbo or supercharger). These are pretty expensive 4-5 figure options. If money is no issue you can get a 996 engine into it, complete with turbos, see RUF, Gemballa, etc.
The cheapest way to get big power (if you are mental) is nitrous injection, but it may end in tears.

Whilst you may get some modest gains, I think you will find that it takes a silly amount of money to make very limited gains. Of course it is down to each individual to determine the ratio and whether it is worth it.

 

[Andy Tims]

ORIGINAL: STolchard

What I'd like to do is add some more low-down torque, and some more BHP.

PX Your 2.7 for an S would probably be the most cost effective.

 

[oliver]

Agree with Andy.

Messing around with a late 2.7 could have a negative effect on warranty and residuals, with small benefits. Try a 3.2 'S'.

 

[jac in a box]

Free flowing exhausts and racing cats can give more power, but this is all at the top end. Often it is at the expense of mid range torque, so I would avoid changing the exhaust.

Not sure that I agree with the above.

I visited Janspeed's factory in the summer where they made a one off exhaust system for my S and fitted free flow cats...throttle response is much improved, can't say I've noticed any loss of mid range torque.
The whole car is definately much improved with the added benefit of a fabulous snarl when given it's head - quite addictive!

Matthew Stone at Janspeed is the man to talk to you.

Jackie

 

[Guest]

Thanks for all your help chaps. JacIaB, with regards to the Janspeed system fitted to your S, how much did this cost, also how labour intensive was the work?

Many thanks, Simon.

 

[jac in a box]

Simon,

Total cost £1k, it's around £500 for the exhaust, £500 for the cats - fitting included.

Took around a day to manufacture and fit...They just dropped me off for a days shopping.

As an aside my OPC set their eyes - and ears on it and gave it their seal of approval!

Janspeed's contact 01722 321833...mention Jackie from Scotland if you need a similar set up - may even knock a pound or 2 off!

Jackie

 

[Guest]

If you're happy with it, then fine.
But just be aware that psychologically it will seem faster just if it makes more noise and has a harder edge to sound.
It's possible it genuinely makes some improvement, but it may only be a few bhp, which is likely to be towards the top end.

In general be wary of any performance claims unless there are dyno results to prove it.
Whilst I'm not suggesting that there is anything wrong with Janspeed, there are plenty of people in the tuning world who make exaggerated claims.

 

[oliver]

Stuart is quite correct.

There is a condition known as 'upgrade-itus'. I've had it for years with my Caterham. It involves convincing oneself that something can be improved and the belief that spending more money on the latest technical development or ingenious new gadget will somehow provide profound improvements. Truth is, it is usually barely detectable and often has a converse effect. Ask any hi fi buff.

A sports exhaust can be a nice addition, but any performance improvement is probably psychological. If you do go for a non-Porsche system, hold on to the original, as most OPCs would not retail the car with an unapproved system.

Why not try a 3.2 'S' and decide if this would be a worthwhile upgrade.

 

[Guest]

Many thanks to all. I am going to try a new Boxster (mk 2) this weekend, and will prob make a decision based upon this.

Again, many thanks

Ciao, Simon.

 

[Guest]

excuse the new boy (I am a PCGB Member, don't know why it does not show).

There can be issues with replacement exhausts losing mid range. However, I have to disagree with the 'for more torque you need more fuel' comment.
The reason mid range torque can be lost to small top end gains is due to badly designed exhaust systems. The reason being two fold. Back pressure and Gas speed.
Firstly, if you install an exhaust with a bigger bore, you loose gas speed at lower revs causing a loss of Torque. Secondly, back pressure is lost and as a result, can not assist in closing the valves. The next issue is fueling. Any car is fueling lower than ideal to ensure emission laws are met. I won't rattle on too long on this subject with reason why and theory unless someone asks. However, I have listed a few tips below.

Exhaust:

If selecting an aftermarket exhaust, ensure that the bore is not bigger (or not by much) than standard. Ensure the free flowing element is in the design of the silencer attached. Free flowing cats will improve power. Bypassing the cats on an S will show up to 5% increase in torque and BHP for example.

Breathing:

one of the cheapest add ons (which will not show any benefit on it's on, only as a part of a 'stage one tune') is a K&N filter. this will allow the car to breath easier. IF you install a vacuum meter on your inlet manifold, run the car up to say 3000RPM and check it with the standard filter then the K&N, you will less of a vacuum on the later. Also, you can buy this new from Ebay for around £27.00

Fuel:
The 'ideal' is to take the car to a chip tune shop once you have your exhaust and K&N and have your cars fuel map set up. Keep in mind the ideal set up you receive will be for the temperature, dampness and barometric pressure on that day. The biggest variant will be summer/winter. You are better off being able to switch out or remove the modchip for MOT's then you can have it running a little rich in the summer (5% rich at max revs is optimum) which will give you a very crisp feel in the winter and as if it has something a little extra.

I have a full Stainless system on my 'S' with K&N and it feels better right through the range. Also it does have more power and torque! I purchased this software www.digimoto.com you set certain parameters and run the car in 3rd gear. it will estimate your BHP and Torque (there are demos on their site). I did this before and after to see the difference and I got a show 4% increase in power and 5% increase in torque (bhp showed as 243 and increased by 9 hp to 252).

My system uses the original joining pipes form the cats to the silencer which are a small bore, thus the gas speed stays up! The car does feel a lot crisper now too. It will not leave another S behind and may just have a bumpers length lead on a quarter mile but it feels a whole lot better and sounds fantastic now too!

I have a phoenix full system with free flowing cats (second hand on Ebay for £500.00)
K&N Filter. Ebay £27.50


That's it!

I have made it brief not to bore anyone too much!

JJ