Air-to-Water IC core incorporated into intake manifold plenum.
 

Due to packaging constraints with my current project and it being rear mid-engined, I am limited to air-to-water (A2W) IC's as my only practical choice. I looked at the barrel designs offered by PWR and liked what I've read about them, however, I could only locate a sufficient flowing barrel IC in a location where I don't want one. Another option is the Spearco type "box" units. These are slightly larger but more configurable to fit my particular application, especially since the cores alone can be ordered and built from there. In case you didn't know, A2W cores are much, much smaller than A2A cores.

This brings me to my question about whether or not it is a good idea to build an intake manifold around an A2W core. For example, put a TB on the inlet side of the core (i.e. before the IC) and an expended plenum on the outlet side of the core with each ports runners coming right out of that. As a result, the only IC tubing would be from the turbo to the TB.

My concerns center around having the TB before the IC core and even distribution of equally cooled air to the ports runners. They may be non-issues but the idea is a little unorthodox to me so my concerns may not be valid. I may be overlooking other issues as well

This would be ideal for my setup because space is proving to be a real challenge and this could certainly simplify and consolidate things. I've never seen anything like this done before but I'm sure someone out there is doing something like this.

Any thoughts, opinions, pics, or references would be great.

\do some research into laminove cores, they are ideal for what you are doing.

Thought about it, I really did! My problem is that I am not running a conventional manifold (I have a jay tec). What I had in mind was an intercooler between the intake manifold and the TB, but I quickly discarded that idea, since the injectors are on the TB. I then thought of an intercooler on top of the TB, but I ran into clearance issues with the hood. The last alternative was after the TB hat, but at that point there was no point in reinventing the wheel.

I ended up with a chinesse W2A intercooler, and plan on upgrading if it works as I had planned.

This article was the one that got me thinking:
http://www.musclemustangfastfords.co...all/index.html

I put ALOT of thought into A/W Intake manifold but i think my biggest fear was what if it don't work,,Then what do you do lol. start over. Another thing is the limited space. Right now im going to see how the china A/W core works that i got from frozen boost. The mustang below is a perfect example how it should work but i dont think everyone gets that lucky.

Rxheven, i think if yo have the equipment to make the runners equal in the manifold and a place for a ice box and heat exchanger i say go for it....But what if it don't work then what would you resort to?

Thanks for the link to that Mustang article. That is just what I was thinking of with the exception of a reservoir for ice. I'd run it without a reservoir. I can fit a large enough (surface area) heat exchanger where I want with a pair low profile fans. I've always been skeptical about A2W on road courses but the more I've looked into them, they seem the better choice. There are many NSX, Lotus, Porsche and other cars using them though I have not seen an IC core integrated into the intake manifold.

As long as you can size the core(s) appropriately and keep the water from heating up too much, I don't see why it wouldn't work. If it doesn't, I'll have to start over I guess.

Those Laminova cores look very interesting. I found out that many NSX guys are using them as well as others and even the Chevy Cobalt used them as OEM, though they no longer do and have reverted back to the traditional bar and plate design (not sure why...cost?). I'm just not to sure about making a one off manifold around them is what I want to tackle with all the other things I have going on with the build. They seem to be far more complex than the bar and plate designs. Perhaps I need to research them a bit more.

I've got about a dozen laminova cores sitting on a shelf right now at the shop. Haven't used them in an application, but I think it is safe to say that if you don't have access to a CNC or milling machine that constructing a housing for the cores with the necessary tolerances to optimize them could turn into an exercise in futility. They are a whole different animal in the level of complexity as compared to the standard a2w units.

Dave do you not have a space at the bottom of your chassis to lay a normal IC flat and build a scoop to direct air up to it? Same principle as a hood scoop just underneath. ;)

Nowhere to do that.

I thought about doing an A2A on top of the engine and pulling in air from the top but that would require a whole lot of very creative bodywork that I do not want to do. Some Ultima GTR guys do this if they run an IC but they have a bit more room height wise to fit a core and different type of ducting.

Ever considered running a rear-mounted radiator to make room up front? I have a friend doing this in a DSM, looks fairly promising. Definitely makes room up front.

Not interested in that either.
There is another SL-C owner who has put a radiator in front of each rear wheel but he has also significantly widened the body in that area to accomodate them (and the 17" wide tires). The car is so wide now that it wouldn't even fit through my garage door. My car barely squeezes in now as it is.

The other cars rear view:
https://www.rx7club.com/attachment.p...1&d=1289510749

https://www.rx7club.com/attachment.p...1&d=1289510749

Another downside is the 20 feet of IC tubing you'd have to run for an IC up front. The original prototype SL-C had a twin turbo Lexus V8 in it with with twin intercoolers laid out much like you see with the radiators above. For me though, I'll be running oil coolers in each of those spots.

I've drawn up something and will be providing it to Spearco to see if they can make it happen and then weld it to a Phil Laird intake manifold. He said he has also done this with great results and is providing a few pointers for me.

check out the yamaguchi FC book, mazda basically did do a W2a IC as part of the intake, for the turbo 13B engine, that later made it into the bonneville FC.

i think they actually had a weber IDA style down draft intake and TB, and the IC was like in place of the airbox.

mazda also used and A2w and A2A core on that car, so its a legal move to use 2 small IC's or something too.

mazda used the motor in something, i wanna say 737? they had mixed results, and then went 3 rotor NA.

I can't wait till I can afford to buy one of those kits.


Dave I cant see why you wouldn't be able to run the oil coolers on one side and IC on the other? What size oil cooler you running now?

Thanks J9, I looked it up.
Btw, are you going to be at the 25 hrs. this year?

A little rotary history....
There was indeed a dual intercooled twin-turbo engine. Not sequential turbos but one turbo per rotor. There was indeed also one A2A and one A2W. All I could tell from the pics in the book was that the IC's were on top of the engine and fresh air was supplied from a roof scoop. The engine was also fuel injected (though the pic does look like some Weber setup) and bridge-ported with 7.5:1 comp ratio. Rated at 500bhp @ 8000 rpm. The engine was supposed to be in the 727c but proved too much power for the little car and was placed in the March 84G in 1984.

It was mentioned that the A2W intercooler has been used on NSXs. Here is a link to pictures of just such and intercooler. It's an interesting build to read through. If you're wondering this car is wicked fast!

Guy

probably not, we're not running a car :/