SPI Injection Pressure
Turbo Mini Forums

I've managed to gety hold of a SPI tank with integral pump for my injection system.

My Haynes manual states that the SPI fuel pump delivers 1.0 bar pressure.

Can anyone confirm this?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Spi is 2-bar max i understand. The pump delivers an amount plentiful for a Carb'd A-series turbo - But It'll struggle to work 3-bar rails, espeially when you start adding boost and raising the pressure.

So if i'm using the SPI tank and 2 MPI injectors, I need a 2 bar pressure regulator - any ideas?

That should flow enough for about 130 hp, based on the Megasquirt guide.

I'm going to test the injection out on an N/A 1275 to start with so no problem.

For the 998 turbo I shall need a 3 bar pump and regulator then.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Personally - I'd avoid the SPi pump. MPi units are out there - Sell what you've got and get one of these.

Peter

Editor

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Seven Magazine
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There is a difference...

And luckilly i have an SPi AND an MPi tank in my storage. I will locate them shortly and identify the part numbers / visual differences - and add something to the FAQ / knowledge section.

Yeah dave is right bin the SPI tank it runs 2bar vmax the MPI is the one to go for, I have just taken delivery of a 13000 miller, the MPi should run 3 bar but still may not be ok on boost, but you can fit a higher pressure pump in the mini tank.
The main thing is to get the tank with all the fittings then you can just fit and forget unless like me you have to reloate the filler neck, but thats just me being different!
You don't need a swirl pot etc as the mini tank is so tall and norrow.
I will let you guys know how well they work in a couple of weeks when I hope to run some fuel pressure tests..

Cheers

Nigel

OK guys,

Finally got round to installing the MPI Tank and pump etc, after runnning a few test as I was seting the fuel pressure anyway for my injection setup, the Fuel pressure went up to 5.5bar which is enough for what I need to do, there was still some adjustment on my FPR so it might go higher?

I ran the pump till the battery went flat so everything was running for ages.
We will have to wait until I have the engine running and on boost for the final results but it looks good..

Nigel

Good to know Nigel...

Do you have an andjustable FPR? If so - do you fancy trying to up the pressure a bit - see at which point the pump starts stalling?

SPI rail pressure is 1bar as stated in the Rover workshop manual

the spi pump is too low delivery and pressure , with my supercharger /M3d setups the mpi pump will supply enough fuel for about 135 bhp max , after this i use a replacement in tank pump rated at 300 bhp , its smaller than the mpi or spi unit and costs £90 inc with wiring and new bag filter

So presumably just cut of the SPi pump and fix the high pressure one. I will try and find some compression type fitting to hold it all together.

Presumably any Walbro type in-tank pump will do as long as it can deliver enough fuel. Should be able to work out how much.

What about the electrical connections? The SPi pump uses a special connector.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

just out of interest, anyone know how much fuel an spi tank is good for?

I've seen the future and tbh its Pie

7.5 english gallons - just like any late-70's (ish) on tank.

Yes, all post 76 tanks are 7.5 gall, the earlier ones are 5.5 gall.

Here is a test I ran on my SPi to find out ho far the car would run with a full to the brim tank and for how long after the needle stopped reading at the bottom of the red

Right ok not the best forum in the world, biut you live and learn.

http://www.theminiforum.co.uk/forums/index...showtopic=18838

Oh and yes, I wouldnt expect any of you guys to get 38mpg

Edited by Sprocket on 14th Apr, 2006.

oops, i meant a rough guide to how much fuel it can dish out/bhp's worth, not how much it holds.

Edited by andeh on 15th Apr, 2006.

I've seen the future and tbh its Pie

You stupid boy Pike...