Limited Duration Extra Turbo Boost

[Malcolm Robb, LC 0112G]

I have received a little extra information about the turbo boost behaviour 
in my car (Lotus Carlton, or LC for short, 1228831 P4 ECU) from a usually 
relyable source. He claims that the LC emissions were not clean enough to 
pass the normal requirements of the Swiss authorities back in 1990. But at 
that time, there was an exemption for so called 'super cars' which ment 
that things like Ferrari's, Porche's, Lamborghinis etc, didn't have to pass 
such strict requirements. To qualify as a 'super car', the manufacturer had 
to proove that the car could beat certain 0-60MPH and 0-100MPH times.

(P4 EFI content coming up chaps !)

To meet these acceleration times, Lotus are supposed to have added a 15 (or 
25) second duration extra boost capability, possibly implemented through 
the waste gate solenoid duty cycle. Does anybody know anything about this 
type of code in the Turbo P4 ECU ? Is it possible to extend this time 
indefinatly (head gasket and temperatures permitting ) ? The normal wast  
egate opening pressure is 1.55BAR (8 PSI boost) and the engine has a 2 Bar 
MAP sensor, so it could/should be possible to get to (say) 1.9 bar (13+ psi 
boost) by varying the solenoid duty cycle, and still keep the MAP sensor 
within range.

I've read TurboP4.pdf a couple of times, and can't see anything in there 
about it.

I know it's a long shot, the '8831 being so rare, but I thought someone 
might know something,.

Cheers,
Malcolm Robb, LC 0112G


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