Sc injection kit & Return line T piece question..
Turbo Mini Forums

so im going to buy the sc kit in good time, just saving up my pennies and im very close.

i was thinking it would be best to take my tank out & get a boss welded in? in my traveler/Van tank

now my mate told me about the T piece trick? would that work for injection?

is anyone running anything like this? i think for a turbo maybe?

i'm going to run a sc12 kit with this set up.

does anyone have a diagram for it? maybe something in shitty pain shop pro even.

trying to get my head around how it works.

one other thing running this compared to meag jolt & a carb would it run alot smother?

Edited by NickG on 1st Jul, 2011.

You need a fuel injection style fuel pressure regulator for the SC kit (they can supply a suitable one). The T piece trick is only used to help the fuel pressure in the carb stay consant with the boost pressure. Not relevant in your setup

I think what is meant here is a T piece on the feed from the tank and put the return in there?

yes i'm a bit of a novice on this but for the return of the fuel line, instead of welding a bung in my van tank, maybe i could T that back into the pump again? it would be lower pressure so could work?

Edited by NickG on 1st Jul, 2011.

Worked fine on my turbo like many others.

Ah.... That's what we've done on the van and has been fine

I think the easiest solution is to fit an MPi tank. Why re-invent the wheel?

Putting a t-piece in the pump feed might work, but you need a consistant pressure for injectio, unlike wit ha carb, where the occasional change in pressure will not affect running.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Hes got a traveller/estate/van, can never remember the proper word.

And nick thats what i was thinking of, couldnt remember if the t piece trick was for returning the fuel back to the tank.

In boost we trust

In which case you definately need to fit a swirl pot and 2 pumps, or be clever with the tank.

My sabre sprint has an estste tank and the injection pump does not like lifting the fuel out of it. You get away with it with a carb, but you wouldn't with injection.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Personally I wouldn't do it on injection because the pressure in the regulator is an awful lot higher so when it spills back through the regulator it is much more likely to produce vapour bubbles in the return line - not a problem spilling back to the tank as the vapour will simply layer out over the fuel, but if you feed back fuel with vapour bubbles to the pump, it will cavitate more easily and have a reduced lifespan (and an irregular output pressure like Wil says).

Schrödinger's cat - so which one am I ???

What if the return was t-eed back after the pump with a valve?

In boost we trust

The 't-piece trick' was an external by-pass for the carbs, when (for whatever reason) the air-volume above the fuel in the float chamber was not being properly pressurised by the higher pressure in the plendiniumium chamebrer.

The later 'T-piece instal' that is getting confused with, was having the return from the regulator tee'd back into the line before the pump. This system worked fine for many, and simplified having to instal a return into the tank.

For full EFI, there is only one way to do it - instal a return line. Weldng tanks is totally not a big deal. I half-fill them with water and swill it around twice, then leave open to vent for a few minutes, and then put about an inch of water in the bottom just to satisfy my own mind that if anything did happen, there is water present to stop anything before it gets too bad....

I've never even had so much as a fluff of explosion or flaming.

Edited by turbodave16v on 1st Jul, 2011.

I bet Jimbo's seen exploding fluff!

Righto so bung it is, my next question would be where do I get the bung welded on the tank?

I don't want to hear the fuel getting returned if I'm low on fuel? If to high up the tank?

I might hear it dropping back in?

Where would be best for the return line bung to be welded in?

If you are using an estate tank, the return is not the problem. Getting fuel out is.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

I have modified two long wheel base Mini tanks for a fuel return, easy to do, and yes, you certainly need a swirl pot and lift pump, otherwise you will have to ensure the tank never drops bellow half full, and then drive it like your Gran, which pretty much defeats the whole point.

Ok, I was going to use a external high pressure fuel pump. So I still need the swirl pot? And lift pump? I was hoping it was going to be easy! :)

Read what sprox says....

If you have less than 1/2 tank of fuel, under healthy cornering you can have your pickup sucking fresh air instead of fuel.

So instead, you have a pot that is basically permanently full.

This is initially filled by a small electric fuel pump (like a pump for a carb mini).

The the efi pump then sucks fuel out of the bottom of the pot, and the return from the fuel rail is into the top of this pot.

At the very top, you have another larger-bore pipe, which returns the excess fuel back to the tank.

What this means, is your main pump is always pulling from a 'full tank' albeit a small one, rather than the main tank which has the fuel sloshing to one side or the other (and hence allowing the suction pipe to suck air) under heavy cornering.

It does mean that if you put on your slicks and drive around in a circle on full boost and less than 1/2 a tank, the swirl pot will eventually run dry (becuse the small lift pump is sucking air from the main tank) but the chances of this happening are zero in reality.

It is all not as bad as you might think - clearly sprox has done more than the rest of us on estate tanks, and I'm sure he'll post some pictures shortly

Edited by turbodave16v on 1st Jul, 2011.

so something like this? I originally was gOing to buy this but jon felt
I did not need this at all, I'm not sure where to get my tank moded as I can't weld
Yet

Could any tank specialist make me one?

http://www.webcon.co.uk/shop/shopexd.asp?id=12808

Edited by NickG on 2nd Jul, 2011.

Have a read of this Nick,might give you food for thought...

http://www.stallard-engineering.co.uk/stor...ubmanestate.htm

Thanks mate few options

Doing the tank is out of my skill level though but I'll work something out

I suggest as Sprox and dave say,

I silver soldered my fittings into my fuel tanks, pretty easy with a decent blow torch,

apart from that, you shild be able to find a suitable swirlpot on ebay, and just feed it with somthing like a facet red top,

[img]http://ww2.justanswer.com/uploads/350matt/2010-08-19_140629_swirl_pot_diagram.JPG[img]

somthing like this,

http://www.ebay.co.uk/itm/Race-Rally-Perfo...=item2ea6da2d87

You could use a VW GTI fuel pump which has an integral reservoir.

Geoff

also if you were to stick the pump in the tank like in the link below I'd sugest slicing the tank in half and adding baffles.