03) Lets See if this Motor Fits

The W8 motor is originally installed in the Passat longitudinally and the Elise's 1.8l is mounted transversely which gave for a bit of cutting needed and not long after that the first test fit was looking good!

With the motor in place, it was time to fit the body and see what we were working with. You can measure all you want, but until you have cut enough away to slap the motor in, you don't know what you are working with. The mock up transmission is from an AWD audi s4 and about 10" longer than the Euro spec FWD 6 speed Audi transaxle the car will receive, so ignore the rear output hanging past the rear of the car!

Now the keen eye will notice that the intake is a little too tall, but it just fits so well in the engine bay. At this point having the hatchback of an Exige would have been very helpful:

Here you can see the center differential hanging out the rear:

A quick notching and plating of the rear crossmember allowed the transmission to sit low enough to clear the stock trunk:

We can weld steel up just fine, but when it comes to TIG welding we don't have a welder and our MIG work on aluminum is just for holding things together to get properly welded. So our luck came through with the Lotus being aluminum all the way to about 4" behind the cabin and from there a mix of painted and galvanized steel allowing for quick modifications. We still needed to come up with a way to build engine mounts without having to modify the aluminum structure. The Lotus uses a bolt on structure for a lot of their components, and with the Elise this is the front mount of lower control arms on the rear suspension:

These are placed in a very convenient location for building a subframe for engine mounts. This is one of the places where engineering a lighter subframe would be far more into the proper Lotus approach, but added strength will help with the extra weight of the motor:

Given the extremely tight clearances we are working with solid mounting and went right to the subframe with some captured nuts:

Then moving farther back a transmission mounting system was built that doubles as a brace for the section of the rear subframe that was removed:

That completes the mounting set up, it might not be the best system, but with the clamshell off and everything disconnected, the motor can be out in 10 minutes. Next section will be sorting out the shifter so check back in.


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