Re: [doc] French Car

[Martin Gutkowski <webmaster@xxxx>]

The Island twin turbo boosts the L and R banks independently, however 
this is still NOT an engine suitable for forced induction. The crank is 
odd-firing and as a result, the pistons do not counterbalance 
each-other, there are counterweights on the crank which if you change 
pistons and conrods, will be wrong. However there are low compression 
pistons available in the US. To quote God "if the odd-firing PRV could 
be properly tuirbo'd, why did Renault go away and replace/redesign 
virtually every part of the engine for the even-firing R25 Turbo and 
Alpines?"

The problem with NOS is supplying enough fuel - the stock fuel pump 
cannot maintain the control pressure when the the extra injectors are 
firing.

Martin

Kevin Milliken wrote:

> Hi Chris
>
> Couple of questions and thoughts,
>
> The firing sequence on the volvo engine is uneven as it seems they are
> grouped in twos. Therefore the way is to use a bi-turbo setup with a
> seperate inlet and carburation system per bank. As it looks as though from
> memory that each bank fires alternately, this would then provide an even
> boost pressure.
>
> When turbos are factory produced (not Deloreans) the compression is lower
> than a conventionally aspirated engine, to take into account the boost
> pressure. Are the deloreans which have a turbo fitted running different
> pistons and con rods? to decrease the compression or is the boost pressure
> set lower to stop the engine meeting its maker?
>
> The alternative could be to just to fit NOS, apparently this will produce
> from 50 bhp upwards depending on jets.
>
> Let me know you comments when you have minute, keep cleaning the Paris car.
>
> Regards
>
> Kevin #5959