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How can it lower intake temps, it is only sprayed on to the intake valves. Ethanol would definitely cool the pistons more for a given power output but that just gives you a reason to heat them up some more.

I saw 900 degree temp in my manifold at Sandown running ethanol, if you push hard enough it still can still melt things, just at a much higher output.

How can it lower intake temps, it is only sprayed on to the intake valves. Ethanol would definitely cool the pistons more for a given power output but that just gives you a reason to heat them up some more.

I saw 900 degree temp in my manifold at Sandown running ethanol, if you push hard enough it still can still melt things, just at a much higher output.

How can it not cool the intake charge? Alcohol evaporation will reduce temps

Can you work out for the kids at home how much it will cool the intake air in the microsecond it has before it enters the cylinder, at the speed of sound? I doubt it would even register on your calculator.

Yes the ethanol will cool the charge slightly in the bore but it is a minuscule amount, and would more help slow the air heating imo. (it definitely won't be cooling it down inside there at wot.) If you want to cool the intake charge you would need to spray the ethanol much further back in the intake to give it time to evaporate. I think if you are that worried about the intake temps by that point you have other issues.

We are much better off trying to cool the bore, as that is going to produce more heat than any other part obviously. Direct injection of water into the bore on the exhaust stroke sounds like a better option to me. I will be trialling it soon on a high comp VQ25DD running e85.

It's not the temp in the plenum that matters

It's what reaches the chamber

Alcohol works wonders for cooling, look at methanol drag cars, they don't really need radiators (or very small ones at most) as with big rads they don't get up to temp

E85 won't cool as much as not as much is used (plus chemical differences)

But I'm sure a rich e85 tune would be nearly as good

Cheers for the Input guys, i'll stick with the intercooled E70 setup then. What excites me is a single turbo manifold for the VG30DETT has been developed, and my next engine will have a built bottom end and a precision 6466 hanging off it ;)

Can you work out for the kids at home how much it will cool the intake air in the microsecond it has before it enters the cylinder, at the speed of sound? I doubt it would even register on your calculator.

Yes I could

please correct me if Im wrong but everybody keeps comparing wmi with E85 sure it helps you run bit more boost and timing on boost but I don't believe you will get the OFF BOOST gains with wmi and just how much better your motor runs fullstop on ethanol :)

I think the focal point here is that lower charge temps help reduce combustion temps and its high combustion temps and pressures that help promote detonation - depending on how well developed the engine is to start with .

A .

I can't remember the exact chemically correct AFR for petrol E85 and methanol but I think it comes out something like 14.7:1 / 8.8:1 / and ~ 6:1

Whatever fuel has to vapourise because most fuels as a liquid don't burn too well . Throwing in approx 1/7 of the total charge mass as a vaporising fuel would make methanol a virtual freezer compared to petrol . E85 would be almost 1/10th the charges mass and petrol approaching 1/15th .

I'd say the greater the charges fuel mass is the greater the evaporative cooling will be provided it changes state to a vapor that is .

Can you work out for the kids at home how much it will cool the intake air in the microsecond it has before it enters the cylinder, at the speed of sound? I doubt it would even register on your calculator.

Yes the ethanol will cool the charge slightly in the bore but it is a minuscule amount, and would more help slow the air heating imo. (it definitely won't be cooling it down inside there at wot.) If you want to cool the intake charge you would need to spray the ethanol much further back in the intake to give it time to evaporate. I think if you are that worried about the intake temps by that point you have other issues.

We are much better off trying to cool the bore, as that is going to produce more heat than any other part obviously. Direct injection of water into the bore on the exhaust stroke sounds like a better option to me. I will be trialling it soon on a high comp VQ25DD running e85.

when we say intake air it would obviously be after the injector, how would it possibly be anything else.. the ethanol would be vapour going into the cylinder and have its cooling effect then, if it was anything but atomised/vapour then surely the engine wouldnt be running too well because it would be trying to compress a liquid would it not? I would imagine it would be like throwing some water on a hot pan, instant vapour and reduction in heat .

I doubt drag cars would not have a radiator because there running methanol, wouldnt it have more to do with only running for 400meters and for like 2minutes?

Edited by SliverS2

when we say intake air it would obviously be after the injector, how would it possibly be anything else.. the ethanol would be vapour going into the cylinder and have its cooling effect then, if it was anything but atomised/vapour then surely the engine wouldnt be running too well because it would be trying to compress a liquid would it not? I would imagine it would be like throwing some water on a hot pan, instant vapour and reduction in heat .

I doubt drag cars would not have a radiator because there running methanol, wouldnt it have more to do with only running for 400meters and for like 2minutes?

They generate a lot of heat just from HP but it saves weight and there is enough cooling from the fuel to get them to the finish line. They shut off after that and get towed back.

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