I've been thinking a lot about how to modify my W2A IC and intake manifold setup, and I'm leaving this open to discussion.
These images (of my existing setup) show the physical locations of all the things that are most relevant:
Originally I was going to keep the heat exchanger in the right engine bay vent (and add a front mount heat exchanger of course, in series), and remove the heat exchanger on the top left of the engine bay, but I've been convinced by kameleon that there is no point keeping any heat exchangers in the engine bay. I was reluctant about undoing what has already been done, but I've almost accepted that I should only have a front mount heat exchanger.
Also, as mentioned previously, I want to upgrade to an aftermarket intake manifold/plenum.
The positions where my existing water hoses come out of the rear firewall from the W2A barrel (one behind the plenum with a 90 degree joiner, and another on the right of the plenum) would currently prevent me from using any of the bigger aftermarket plenums, due to lack of clearance. Given that I'm probably going to remove my W2A heat exchangers from the engine bay, I'm somewhat open to moving the water hoses so they come out of the firewall in different locations. I'd rather not, because I don't want to have to patch up heaps of holes in the firewall and make lots of new ones, but I won't rule it out.
Anyway, this is my latest idea:
- Move the W2A barrel upwards so it is just below where the 2 water hoses go through the rear firewall, and keep the hoses in the same locations in the firewall
- Keep the left/hot air pipe (from the turbo) coming out of the firewall in the same place, but just change the bend that goes into the barrel on the left
- Have a straight-runner (best for performance), right-side-feed plenum poking through the firewall where the barrel is at the moment, ie. directly below the proposed barrel location
- Completely remove the entire existing post-barrel piping from the right of the barrel, and cover up that hole in the firewall, leaving the top of the engine completely unobstructed
- Have a short U-bend from the right of the barrel directly into the side-feed throttle body below it in the boot (I need to consider that there would need to be plenty of flex in this bend)
The only thing I don’t like about this is that I would have a gaping hole in the boot for the plenum to poke through. Originally I was totally against anything like that, but maybe I could learn to accept it. I would try to engineer some way of reducing the chance of dirt or water from getting into the boot through the hole around the plenum/runners.
Besides, how awesome would it look having the barrel directly above the plenum in the boot, and having nothing on top of the engine.
I should also mention that I would rather not change the W2A barrel/IC itself, as that is one of the most expensive parts related to this situation, and it seems to be doing it's job quite well already (the heat exchangers are the problem). If I was going to change the barrel, now would be the time to do it, but I won't change it just for the sake of it.
I'm open to discussion and other ideas, mainly regarding the intake manifold/plenum, and how it would affect the locations where hoses and pipes go through the firewall.