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Crossflow plumbing.
paulf - 25/7/02 at 10:05 PM

Is it vital that i connect the water outlet from the inlet manifold into the cooling system? I assume it should be plumbed into the bottom hose if used.
Paul.


theconrodkid - 26/7/02 at 03:42 PM

It should be in the system as the water running through it warms the manifold,you can use it as intended,to feed the heater or if you dont have a heater connect it to the elboe on the water pump


Jon Ison - 26/7/02 at 04:06 PM

for outright power i would NOT send any water thru an inlet manifold, the cooler the air, the more power it makes....cold air is like me, "Dense".


paulf - 26/7/02 at 06:38 PM

My thoughts exactly ,all though it will take longer to warm up i suppose. It will make it simpler to plumb in as i have a bottom hose with no means of tapping in to it. As long as the car will start and run i am not to fussed as the crossflow engine will not be in it for long.
Paul

quote:
for outright power i would NOT send any water thru an inlet manifold, the cooler the air, the more power it makes....cold air is like me, "Dense".


JohnFol - 26/7/02 at 06:58 PM

I don't agree 100%.
The carbs we are talking about are 30 year + old designs. The problem was the atomisation of fuel to give a complete burn and hence more power. The designs of old heated the air to give more "swirl" and hence a finer mist. Also, you don't tend to get polished manifolds as the roughness introduced additional eddy currents within the fuel air mix. Both these things meant more fuel got burnt and hence more power.

With injectors, you have this restriction removes, so you want to cram as much air / fuel in as possible. For example, higher air density by cooling it .. ..

Please feel free to cite some well respected document showing me to be wrong . . . .


interestedparty - 26/7/02 at 07:05 PM

Water heated manifolds are pretty much de rigeur for anything other that flat out competition DCOE type carb engines. Problem is to as JohnFol says to fuel in the air flow rahter than have it drop out of suspension

John


Jon Ison - 26/7/02 at 09:01 PM

2 things......looks like a can o worms this one....

1) I started by saying "for outright power"

2) Its air you need to induce into the clyniders, you can pump as much fuel as you like but without oxyegen it aint gonna burn.

2 sides to every theroy, each to his own and all that, yeap i know you need to keep the fuel in the air flow ect.....but myself i would never run an heated manifold in the type a cars where building/running, unless of course you had no choice, some V8's, V6's ect....

iv'e never tried it, but it would be interesting to see a car on rollers, diconect water, and do a back to back power check....


interestedparty - 26/7/02 at 09:14 PM

I've never tried it either, but it would be my guess that in a flat out power producing situation the difference would be small indeed, the air just wouldn't be in the manifold long enough to absorb significant heat. Where you need the water heating is when you are obliged to drive at the speed of normal traffic, and the airspeed in the manifold is low.

John


Jon Ison - 26/7/02 at 09:24 PM

ah, got it now, thats wot i'm doing wrong...."drive at the normal speed of traffic" sorry, no can do that.


David Jenkins - 27/7/02 at 08:15 PM

We noticed...



David


paulf - 27/7/02 at 09:14 PM

I went to the locost race meeting at Silverstone today and took note of what the racers are doing.Most have blanked off the manifold outlet and just have the top and bottom hoses on the engine.Thinking about it if the original way of connecting the manifold was through the heater then it would be shut off anyway when the heater is not being used.
Paul.

quote:
I've never tried it either, but it would be my guess that in a flat out power producing situation the difference would be small indeed, the air just wouldn't be in the manifold long enough to absorb significant heat. Where you need the water heating is when you are obliged to drive at the speed of normal traffic, and the airspeed in the manifold is low.

John


locodude - 28/7/02 at 05:18 PM

Hi All
A lot of this water heated inlet manifold stuff is to do with carb icing, prevention thereof and nothing to do with power. These engines were originally designed as day to day workhorses and to be idiot proof. Neither of which we need them for!
Chris PTM