New Intake Manifold design by Wagner Tuning

[Zupra1776]

Their EVO2 is still air-water. The Evo2 moves the charge cooler out of the intake manifold into a secondary plenum. Their R&D photos from March talk about moving the water cooling out of the intake manifold into the auxiliary unit you see in the CAD photos.

But air/water versus air/air is not the real debate. Yes, all things being equal, air/water is better. But in practice, It's the overall thermal capacity of the system that matters. Water can handle around ~4X more thermal output than air, but A2W coolers are often undersized (just like the stock Supra manifold!), which gives plenty of room for a larger air-air system to outperform. Of course the answer is to make the a2w system bigger, which many companies have, but air-air systems are great for street cars because they're hard to beat for simplicity and don't heat soak as easily as an a/w system looped through the coolant that's already getting pummeled by keeping the block cool.

If you're gonna drag race and have time to chill the coolant between runs, a2w is great. If you want to package decent cooling into a tight space--like an intake manifold--a2w is great. But it's not the only solution.

Isn't the A2w system on these cars separate from engine cooling?

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[Thraxbert]

Isn't the A2w system on these cars separate from engine cooling?

I believe so, yes. There's a high-temp loop+exchanger and low-temp loop+exchanger. But I was just speaking generally about a2w cars. But the truth is that a2w systems are often used for packaging reasons, giving a tremendous amount of cooling capacity into a much smaller area, and that often leads to the heatsoak issues you see from the Supra under track loads. It's not that a/a or a/w are good or bad, just that they have their own strengths and weaknesses.

 

[Tsuki]

Curious as to why?

There are pros and cons to each, but generally, air-to-water is better.

Biggest con to a2w, of course, is weight, second to that being the added complexity - there are a lot more things that can go wrong, long-term. If you're running enough power to heat soak the a2w loop, I assume it would be more difficult to mitigate that, and it could get expensive. Definitely another con to consider, but overall, once you're past the price of entry, you won't want to go back.

Anyway, a2w will provide a more consistent charge temperature, with a substantially lower pressure loss. Since you're cooling this with a coolant loop, you're not going to have any substantial spikes or dips in air charge temperature, and it's a lot less prone to heat soak. All of that makes for a vehicle that has a more consistent power output, and is probably a bit easier to tune, especially for really picky platforms that don't take well to sudden changes in air density.

The really big thing beyond that, though, is the sheer volume of piping. air-to-air is going to substantially increase turbo lag. Putting it simply, you have to fill all of that volume with pressurized air before your boost pressure starts increasing. The charge pipe on our cars is just about the only volume outside of the head that needs to be filled. If you moved to a front-mount air-to-air intercooler, you would have two pipes at least that length, for the cold side and hot side, along with an enormous heat exchanger, since the air-to-air intercooler isn't as efficient.

I don't know of anything at all positive you would gain by going air-to-air on this platform, aside from a bit of weight savings, and some bling with the big intercooler - assuming you could get one to fit.

 

[underdonk]

The Toyota Prius has a metal intake manifold.

That is all.

 

[Deepseahooyah]

Their EVO2 is still air-water. The Evo2 moves the charge cooler out of the intake manifold into a secondary plenum. Their R&D photos from March talk about moving the water cooling out of the intake manifold into the auxiliary unit you see in the CAD photos.

But air/water versus air/air is not the real debate. Yes, all things being equal, air/water is better. But in practice, It's the overall thermal capacity of the system that matters. Water can handle around ~4X more thermal output than air, but A2W coolers are often undersized (just like the stock Supra manifold!), which gives plenty of room for a larger air-air system to outperform. Of course the answer is to make the a2w system bigger, which many companies have, but air-air systems are great for street cars because they're hard to beat for simplicity and don't heat soak as easily as an a/w system looped through the coolant that's already getting pummeled by keeping the block cool.

If you're gonna drag race and have time to chill the coolant between runs, a2w is great. If you want to package decent cooling into a tight space--like an intake manifold--a2w is great. But it's not the only solution.

Thank you for the explanation

 

[Deepseahooyah]

There are pros and cons to each, but generally, air-to-water is better.

Biggest con to a2w, of course, is weight, second to that being the added complexity - there are a lot more things that can go wrong, long-term. If you're running enough power to heat soak the a2w loop, I assume it would be more difficult to mitigate that, and it could get expensive. Definitely another con to consider, but overall, once you're past the price of entry, you won't want to go back.

Anyway, a2w will provide a more consistent charge temperature, with a substantially lower pressure loss. Since you're cooling this with a coolant loop, you're not going to have any substantial spikes or dips in air charge temperature, and it's a lot less prone to heat soak. All of that makes for a vehicle that has a more consistent power output, and is probably a bit easier to tune, especially for really picky platforms that don't take well to sudden changes in air density.

The really big thing beyond that, though, is the sheer volume of piping. air-to-air is going to substantially increase turbo lag. Putting it simply, you have to fill all of that volume with pressurized air before your boost pressure starts increasing. The charge pipe on our cars is just about the only volume outside of the head that needs to be filled. If you moved to a front-mount air-to-air intercooler, you would have two pipes at least that length, for the cold side and hot side, along with an enormous heat exchanger, since the air-to-air intercooler isn't as efficient.

I don't know of anything at all positive you would gain by going air-to-air on this platform, aside from a bit of weight savings, and some bling with the big intercooler - assuming you could get one to fit.

Thanks for the information

 

[Extreme Power House]

Nice!

 

[METAL]

Will this Evo2 finally fix our charpipe blowing off issue!

 

[zrk]

Will this Evo2 finally fix our charpipe blowing off issue!

Im sorry what

 

[Thraxbert]

Im sorry what

Some people running boost levels much higher than stock can occasionally blow the charge pipe off of the silicone couplers on the 2-piece aftermarket designs. The clamp and coupler setup just doesn't hold, allegedly.

I wager some T-bolt clamps would fix the problem versus flimsy shit worm gear clamps, but a one-piece pipe is even more effective of course.

 

[zrk]

Some people running boost levels much higher than stock can occasionally blow the charge pipe off of the silicone couplers on the 2-piece aftermarket designs. The clamp and coupler setup just doesn't hold, allegedly.

I wager some T-bolt clamps would fix the problem versus flimsy shit worm gear clamps, but a one-piece pipe is even more effective of course.

Oh, yeah, I know. I've had my charge pipe blow at the drag strip. I was just looking at those CAD drawings thinking I don't see how that would fix it.. But maybe.

 

[METAL]

Are those brackets on top of both versions for holding a nitrous rail?

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