Well no massive traiblazer but some might be interested
in my stuffing around at the wreckers for a simple setup.

Its an early 90s Hyundai manifold chopped up with standard
round port flange ends to either be used for a drawthrough
or blowthrough turbo setup (not decided yet).

Chasing 85 hp atw from an a12 so hopefully it should make that
with an Impco 125, log style turbo manifold with garret to17,
water injection and locked electronic pulsar distributor.
Itll look better when its all welded and ported.
Im undecided whether to do do a drawthrough like TopGear which
is neat and tidy or a blowthrough with a small intercooler.
Im leaning towards drawthrough for simplicity which wont need
the throttle body on plenum but on turbo.
Either way you can see the runners into the inlets on the chopped
end section sitting at the top of the plenum. Should provide equal
mixtures to each cylinder. Some strengthening will be needed to
make sure the runners have enough strength to stop vibration damage
yet the whole thing is superlight.

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nice D, should be a weapon, drawthrough would work a lot easier but with lpg, im not so sure you want lpg going theough the imperler of the turbo heat wise.

Blow through would allow an intercooler and remove the requirement for the water injection.

Yeah thats my concern also Mik with heat.
I might have to water inj before it enters the turbo.
Its an experiment, I am aiming on cheap/simple but also performance
limiting inlet design matched to the hp/torque area Im chasing.
I want to make sure there is no waste on inlet charge suspension
like in bigger plenums and runners. There will be a few more pulses
with the single shared runners but still the path is not restricting
like on the stock manifold.
This system will hopefully be the final setup of the lpg/turbo engine
to go into my 1000 wagon but for now will use Dons adapter for
a stock 125 impco NA setup just to get the lpg installed and running.
Petrol is now rising again and Im trying like you Mik to have some
performance without my balls getting squeezed too hard by the oil mafia.

well i did 315km on 26lt of lpg over the weekend, pretty sweet deal i say.

might go single lpg on the L series, might get more power along ewith some economy gains over the rich and gas wasting twin set up.

id be worried with water injection prior to the impeller wheel D, if its not atomised, ive seen some pretty hacked up blades from not having a fine enough mist in the mixture.

Hi D,
I like your engineering.
Not wanting to steer too far off topic.
Is the hyundai manifold you used, the one that has been mentioned before as being similiar in design to the A series inlet manifold. (and could possibly be used as an injection manifold on an A series?)
cheers
Bruce

Mik good points to consider, might have to go blowthrough in the end but
really would like it as simple as possible. The water inj system are pretty
good these days, they spray a very fine mist.
Did that figure you achieved on mileage driven hard or granny style :)

Bruce no problems its not the same manifold as the one highlighted in the past.
Its the one with just before the plastic replacement Ill get the details soon
hopefully next weekend. I think they only came out the one or two years.

Mik thats great economy

nah free way at 100kmh ;) all the way on the free way up and down hills loaded up with roof racks, granny visor, an extra person and fishing gear- eskys. more than the car usually carries by 200kg

i have 1 of these manifold already setup on my a15 oval port.. i dont no how to put pic's on here so if someone wants to post them up i will email pics of my setup to them

jon

With relatively low boost, even up to 8psi, with lpg you will not need any sort of cooling as the lpg is less prone to detonate even as a draw through system. I have seen a few draw through systems using a simple mixer and they worked well enough on mild boost applications (around 6 psi). LPG works well when hot as it burns much hotter in the combustion chamber anyway. the only thing you have to worry about is a backfire which will potentially stall the turbo and at high turbo speeds can be fatal, be it draw through or blow through.

I guess that having an intercooler would soften the blow
on the turbo in a blowthrough in case of backfires.
Now I wonder if I can use some kind of one way valve/flap
to stop reversion/backfire?
Either way most backfires will occur with the old ring mixer
type setups and poor ignition systems.