Is WI the best option for me???

[CosRush]

I have a Kitcar (seven Type) which has a small frontal area, im using the biggest IC i can get in there, but under some very hard accels im hitting the upper limit of my ACT's and therefore my ECU is cutting back power...

I wonder if WI would be the best solution to reduce the ACT's???

Any thoughts or comments on this???

Cheers

[hotrod]

Sounds like a reasonable solution to me. As you say the Super 7 type kit cars have a very small front area to work with.

Since your running an intercooler I assume your supercharged --- I'm not very familiar with the configuration of the kit cars although many years ago I had a friend that had a 1968 Lotus Super 7 so know what sort of lay out your dealing with.

Do you have the Caterham ?

We need a bit more background info to give you any reasonable guesses on the best path to follow. A little bit about the engine and its configuration would help a lot.

Larry

[CosRush]

Thanks Larry,

Its Dax Rush actually, but a similar design to the caterham.

I have a Turbocharged 330Bhp Sierra Cosworth engine, and am using the 4x4 IC which is slightly bigger and more efficient than the 2wd one.

But im at the limit of the IC size, as it would be very difficult and costly to try and redesign the front end to use a bigger IC, bearing in mind that within the relatively small front nosecone is also the radiator.

Ive spoken to a few people who have suggested WI, and i can see that it would be much less complicated than a new IC setup, and cheaper too.
And if what i've read is true, it could be very effective.

Hope that helps in the way of information...

[hotrod]

Sounds like a pretty basic setup then. Look over your piping and see if you can find a convient location between the IC discharge and the throttle body/intake manifold.

Put your spray nozzle there, should be a minimum of 6" from the throttle body if your "space challanged"

Sounds like the intercooler has enough "heat sink" capacity for a quick squirt, but can't handle any repeated or long duration high boost situations.

Most folks with simple systems go with a manifold pressure trigger or a WOT trigger might also work for you. People generally turn the WI on at about 60% - 75% of max boost.

If you get one of the more advanced Aquamist systems you of course could map to fuel injector duty cycle and all that for an even better taylored setup.

You might want to browse through the gallary section and see some pictures of other peoples setups for some ideas.

330 BHP implies you will need some place in the 4 - 8 gal / hr range of water spray capacity ( 250 - 500 cc/min). You should run a 100 psi pump, you can make it work on lower pressures but will get much better performance on higher spray pressures due to better atomization and of course less loss of effective spray pressure due to manifold pressures under boost.

Larry

[CosRush]

Thanks Larry,

Another question based on this setup then,

I have the pipe which runs from the Intercooler to the throttle housing, this would be an obvious choice of position for the jet,

However, after the throttle housing is the inlet plenum(which is dry) .
Inside this at the end of the inlet manifold is each individual intake with rampipe.
The inlet manifold is wet since it is where the injecotrs are fitted.

Would the system be any more effective if i was to utilise 4 jets, mounted onto the plenum, each spraying into each of the 4 cylinder intakes???

[hotrod]

The general rule of thumb is to locate the spray nozzle a few inches ahead of the throttle body butterfly valve. That is frequently the most trouble free for several reasons --- ie accessability usually high on that list.

A few brave souls, have done direct port systems. If you look around here, Richard has a post about the new Subaru WRC car which will be using a direct port setup.

Like direct port Nitrous setups the plumbing is much more complicated. It does if properly done eliminate any wet dry manifold issues. There is some historical evidence that a direct port system is slightly less effective in some regards to a system where the spray occurs farther back. NACA found they consistantly got slightly higher max power settings when injecting well away from the cylinders so there was time for maximum charge air cooling to occur. In the WRC car intake valve cooling may trump that small difference, if they are fighting reliability problems due to high valve temps.

I personally would be inclined to investigate the simple single point injection setup first and only mess with the multipoint if you need to !!

Larry

[CosRush]

Thanks again for the response Larry.

[GotH2O]

@100spi water pressure and 0 psi MAP, nozzle sprays 300cc/min

how much will the same nozzle spray @21psi MAP?

[hotrod]

About 267 cc/min.

square root of ((100 - 21)/100) X 300 = 267

[GotH2O]

thank you!