You have heard people complain about sticking a Small Block V8 into a compact car and how little room they have. As a glutton for punishment once I had the W8 fitting I decided mid engine turbo noises was another thing this car needed. I almost gave up though, with my choice to not cut the rear fiberglass and my inability to fit the turbos after the rear subframe and still get all the charge piping and plumbing where it needed to go. I also attempted to go with a single turbo since there was so little room for a pair of turbos, but the transmission goes from bottom side of the trunk to top side of the diffuser leaving no room for a crossover pipe anywhere:
This is where an unexpected pair of pick up truck turbos came into play. When Ford introduced the Ecoboost F150 few people looked at their turbos for retrofitting into crazy projects like a W8 Lotus Elise. Still not sure why more people aren't using them they are symmetrical castings, billet compressor wheels, ball bearing cartridges and both water and oil cooled:
Best of all at the time a pair of rebuilt turbos could be had for less than $600, you have to think about how many F150s are out there and how many are up in the miles needing rebuilt turbos, so they are plentiful. Most important for me, the turbos are extremely compact and able to fit in my already full engine bay:
https://lh3.googleusercontent.com/39CD2gI6_LUe8x_pOERhkv-1LBL9Rw-E4HiGjz9fI6xyaJUmSEGNPbspw588ObGM92RJKd0XMbUP5NGh6Rri7xfnphspZO2EpRQEwVHGdCZz4CVVIFCe0YWwIcONKSdePvaqtAhz0w=w2400
With the placement for the turbos decided and them small enough to fit attention can be turned to getting the exhaust into the turbos. The factory manifolds on the W8 are a very unique design with each other exhaust port either running upwards into a runner of its own and the others going downwards to their own runner:
Unfortunately The output of the Manifold was close to 3" per side and way larger than I was able to adapt from down to the smaller inlets of the turbos. Add that to needing to put the turbos farther forward on the chassis the decision to switch to log manifolds was the best choice. Since the W8 isn't common I couldn't just go and buy flanges already made up, and the factory manifolds used a fairly thick flange at the heads I opted to cut them down and use them. With the compact design of the W8 the typical schedule 40 pipe manifolds using elbows and tees wasn't quite feasible, so I fish mouthed pipe lots of die grinding followed and here is what we ended up with:
Compared to the stock manifolds this also gave me a fair amount of room.
Stock:
Log Manifold:
Add a quick outlet pipe and we were ready to mount a turbo:
Some custom flanges were required to be made for the turbo inlets, again since these aren't turbos that are commonly used finding parts was impossible and everything needed to be made. All welded up and the first glimpse of the motor with turbos sitting in the bay:
Then we were able to get an idea of how the downpipes were going to be routed and fit:
So that's how the turbos fit and we press forward.