PING

Hi,

Sorry this is a bit vague perhaps, but here goes!

I would like to understand a bit more about how our cars ''Make'' power ... and therefore how to make more, SAFELY

The turbo boost level is clearly a major factor, but why does my car produce 260ish BHP at 1.1 bar(16 PSIish) and another - say Stephen Dones for instance - produces in excess of 300 BHP at a similar boost?

Breathing mods are a major factor - I have catted standard exhaust and an ITG Panel filter, whereas Stephen has a serious AM Exhaust and serious air intake mods. How does it all fit together though ... what's the realtionship between Air in, Gases out and the effect of the Turbo?

If any one can point me to some info / threads, I'd be very grateful!

Thanks in advance

Steve ''More Q's than A's''

Cosie Convert

Steve


It's all about mass of air flow and what you do with it.

Boost pressure is only a rough indication of actual flow. If you create a free path for the airflow ie big bore free flow intake system, ported or tubular exhaust headers, big turbos, big bore exhausts etc, for the same boost pressure you will get more air flow.

More airflow + appropriate fuel and ignition = more power.

Generally speaking, the lower boost you can make your power at, the safer the engine is.

Andy

PING

Cheers Andy,

So I guess it's a matter of balancing the different factors ... before doing much to the car, it needs improved air intake and gas escape capablities.

I've had the TEK2 remap done and an ITG Panel filter - great - so my next step must be exhaust. After that it should be getting more air into the system and having the ECU remapped to keep the fuelling right ..?

Once that is done, any more must be a mixture of all three areas (air in, air/fuel ''Processing'' - Turbo - Gases out) again so as not to stress the system in one area too much ... does that seem about right? ... But then we're getting into serious mods!

Still don't quite understand how at the same pressure in the same size turbo, two cars can have very differing power outputs ... surely a higher mass of air passing through the turbo would mean higher pressure from the car which breathes better?

Steve

john banks

Less obstruction to flow results in lower pressure to produce the same airflow.

Cosie Convert

John's correct, Stephens car has tubular manifolds and a 3" exhaust system, this will create less restriction for the gasses therefore more air will flow at the same pressure.
Also worth remembering, is that Stephen's car is running a TEK ?? ie a development map which may be more efficient than a TEK 2

Leaner fuel mix and more timing advance will generally produce more power from the same airflow however it starts to become a bit risky and too little/too much could cause serious damage.

Best left to them that know what they're doing.

Andy

Edited to say your TEK 2 will also continue to work well with a better exhaust system and/or intake mods. The fuel is added proportional to the increased airflow. This is the case up to a limit you are unlikely to exceed on the standard turbo.

[Edited by Cosie Convert - 5/20/2002 1:52:04 AM]

PING

Cheers John and Andy ...

Makes sense now

Steve '' few less Q's now''