scott wrote:
> 
> It's probably not turbo lag, more the fact that the turbo doesn't work 
> properly until around 2200 rpm and the throttle is very heavily damped 
> by the ECU.  

Still I'd say there's something wrong. Under Saab's hood that engine 
(and turbo) starts working from somewhere around 1500rpm. The way you 
defined here sounds like Volkswagen 1.9TDI (which is older technology 
with really short torque rpm's). For example the Audi I drive pulls at 
2000-3800rpm. Under 2000, it's a nolifer.

> If you're used to driving a petrol it can really catch you 
> out sometimes.  

Yep. My '89 Saab (2.0 petrol turbo) pulls from 1500rpm and trough the 
whole rpm area (1000-6000rpm) nicer than Audi - and it's still turbocharged.

> The biggest difference is around 1500rpm in 2nd gear 
> (common situation when pulling out from junctions that you don't need to 
> stop for), really my 70 BHP petrol engine felt *way* faster than this 
> 120 BHP diesel under those conditions.  Once you are in the 2500-3500 
> rpm range it's fine though.

Turbocharger actually removes some torque from the really-low revs 
('bout <1500rpm), after that it starts to wake up and gets torque much 
higher than with naturally aspirated engine. After driving 6 years with 
turbocharged cars, I wouldn't even think about naturally aspirated one 
:p - once I got used to the sub-rev torqueloss, I've just let myself 
enjoy the long and stable torque (expect for the Audi, which has only a 
short spike of torque, but it's cheap to drive, so...).

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid

Post a reply to this message