How's this for an idea?
One thing that concerns slightly about relying on W.I. is the potential for the pump to be startved of water. This is obviously an issue with the tank running dry and while there are ways round this, I have opted for the optional ERL flow sensor which will be fitted with the rest of the kit. However, more of a worry is when the tank is getting low on water, the possibility of starvation due to the water sloshing around during cornering etc. Okay, baffles etc are an option, but I really wanted something a bit better. So I looked at the fuel system I've built on my Rover rally car. This utilises a fuel cell, 2 pumps and a surge tank. So I thought, why not apply this to a W.I. system?
Idea is to mount a large tank under the front wing where the intake system resonator used to be. Then, mount a smaller tank, such as an oil catch can (like this one - 900ml) -



- up in the engine bay. The idea being that a high power pump flows water from the main tank via the first into the top of the smaller one. When the tank is full, water will simly flow back to the main tank via the second hose. The W.I. filter is fitted at the bottom where the drain plug is and then feeds the W.I. pump. This way, if the car is cornering hard and the main pick up in the primary tank draws in air, the secondary tank will still have sufficient water in it to supply the W.I. pump. Given that the ERL pump is rated at 250ml a minute and the secondary tank is 900ml, the secondary tank should easily have sufficient capacity to cope. A high power pump on the main tank will ensure the secondary tank is quickly topped up when 'normal service' is resumed.
Thoughts?
Gary

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1994 Toyota Celica ST205 GT-Four Group A WRC - running in rebuilt engine....

Sounds like an interesting idea Gary.

This bugged me for a while and I came to the conclusion that I would like to opt for the simple approach.

I purchased a single baffled WI tank - this does away with the extra pump and extra tank solution...maybe a better alternative?

_________________
Kris
95 ST205 - slept for 10 years, now waking up...
Avensis
http://www.gtfours.co.uk
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Turbocharging - the replacement for displacement

Kris
I did consider that as an option, but wanted a belt & braces approach. A baffled tank will help big time, but is no guarantee IMHO.
Gary

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1994 Toyota Celica ST205 GT-Four Group A WRC - running in rebuilt engine....

stevo_st24 has used a bag tank to cure this problem. Interestingly the first 100 homologation ST205's supplied to the UK market had a plastic bag supplied as standard. Initially my reaction was rather dismissive as the bag looked like something you'd buy from Happy Camping rather than a serious solution.

Steve's logic was to use atmospheric pressure to ensure that no air entered the system. He's tried it on track and it seems to work fine. Its certainly a lot better than my temporary setup using a 5 litre plastic fuel tank from Halfords. At certain tracks e.g. Donington, if you don't keep the tank brim full then air gets into the system. The DDS2 monitor gauge is invaluable to monitor this.

Even the original ST185 rally cars had a big red warning light on the dash to warn when the water injection ran dry. TTE clearly regarded it as important.

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

The WI "bag" used on the 205WRC looks something like this...

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Kris
95 ST205 - slept for 10 years, now waking up...
Avensis
http://www.gtfours.co.uk
_______________________________________
Turbocharging - the replacement for displacement

Which is why I have one
Gary

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1994 Toyota Celica ST205 GT-Four Group A WRC - running in rebuilt engine....

I have both a bag tank and indeed a swirl pot in the system

It still needs a little work as the tank (actaully an old camelback bladder) is a little small @ 3 litres capacity with probably two L working capacity

It lives behind the rear quarter speaker on the passenger side

Directly below the tank I have an original chargecooler overflow tank (ST205 one)

This already had 2 connections, 1 top and one bottom

I have connected the tank to the bottom inlet and left the top one vented to atmos (This is also how I fill the system). An additional hole in the bottom ot the tank let me connect the main feed to the pump

It has indeed proven to be a reliable solution and has yet to airlock even under enthusiastic sticky rubber track driving conditions

I should probably also add that I do not use an additional pump.

Since the swirlpot is sitting below the level of the WI tank it remains gravity fed for now

At some point I think I'll probably fit a bladder in the spare wheel well. At the moment I'm thinking of something donut shaped, possibly a small inner tube from a road trailer or somesuch where it will be well out of the way for day to day use

In this case I might need to fit a lift pump depending on the height of the boot floor Vs the swirlpot location. I'd plan on using a windsreen washer pump or equiv in this case.

Another alternative I have been thinking about is a swirlpot setup in the pass. side rear quarter behing the trim. This could have 2 tanks, 1 for fual and 1 for water.

In this case I would certainly need a lift pump for the water. If I go this route I'll be using the stock fuel pump as a lift pump for the fuel, with a high capacity/pressure fuel pump either in the swirlpot or inline