Control Pressure Regulator/Twin Turbos [long]

[Martin Gutkowski <webmaster@xxxx>]

Hi All,

Just for those who haven't read my posts before: A good mate (Rich) and 
I bought two non-running D's and imported them back to England. Mine's 
#1458, a stock 5-speed, and has been running for several months now. 
Rich's is #2727, an Island twin automatic, and was mechanically in worse 
shape (cosmetically better).

In attempting to solve a problem with mine when we first got it going, 
several bits were swapped between the cars. All were swapped back EXCEPT 
the Control Pressure Regulator. I drove about 600 miles with Rich's CPR 
in my D, and it progresively got more and more difficult to start, and 
ran more and more roughly while warming up. Until one evening when the 
car wouldn't start at all. It wouldn't even fire on a single cylinder. 
On examination, the air flow sensor was extremely stiff to depress. When 
I loosened the Control Pressure line (the one from the top of the 
metering head to the CPR), the metering head plunger moved freely again 
and the air flow sensor loosened up (petrol leaked from the loosened 
line unsurprisingly). I took off Rich's CPR and swapped mine back. My 
car started first time and has run fine ever since. The Air flow sensor 
is considerably lighter to depress (engine off).

:On Saturday, we got around to attempting to start #2727 for the first 
time. Knowing there was something up with the CPR I took it apart. It 
was completely clean inside. I blew through both ports with the shop 
air-hose and if there was a blockage, it's gone now! (I could feel air 
passing through). I also undid those four small flat-head screws and 
removed and cleaned the components underneath. (two little plates and a 
funny little cap in between). I then reassembled everything. As soon as 
the pump got petrol into the CPR, the air flow sensor went really stiff 
again.

I have no idea how this device works, but if anyone has any 
hard-and-fast solution for this apparent blockage, please let us know!

Secondly, On #2727's engine, there's a vacuum hose which apparently has 
no business being where it is. Dave Stragand very kindly supplied us 
with the Island documentation, and there's nothing in it about this 
particular hose. He confirmed there's no such hose on his engine.You can 
see it in this picture

http://www.delorean.co.uk/pictures/DCP02382.JPG

It's the the right of the centre of the picture, and comes out of the 
left hand manifold. This hose goes off into a T-piece and one of the 
connecting hoses disappears off into the frame at the far left of the 
engine bay (around the same place as the A/C hoses). The other hose is 
hanging off it loosely. There's about enough length to get it to the 
charcoal cannister but no apparent port or connection for it. Anyone any 
ideas? I've blocked it with a screw for now. What does the charcoal 
cannister do? Currently all three hoses on the diagram are connected.

Lastly, in talking to Dave Stragand, and reading up as much as I can 
about turbocharging (including picking the brains of firstly an engine 
tunng expert, and secondly a friend who has a raft of self-taught 
knowledge on turbocharging). The Island system on #2727 has no cats and 
employs these very simple pressure sensors on the left intake manifold 
to detect when the system's under boost and disconnects the lambda 
sensor, putting the lambda computer into "slightly-rich" mode. In other 
words, it's a cheap and cheerful way of putting more fuel in the 
cylinders when under boost. In my searching the web, I found this 
intriguing product and one of the comments from the tuning expert was 
"this would be very useful on a modified engine"

http://www.milford.ndirect.co.uk/kstar.html

Has anyone seen this product before?

#2727 does not have a knock sensor either, nor does/did it have a 
re-curved rotor arm (it needed replacing anyway). I think in combination 
with the K-star, the potential for fine tuning an Island twin engine is 
huge.

Best Wishes

Martin
#1458