We had some guys looking at E85 on one of our race engines a few years ago. We were using a CBR600 engine and they did some tests with fuel pumps, injector seals, hoses etc - dumped them in a bucket of e85 and left them for a week. Came back to find a rubber mess and no sign of some of the seals
We did change everything rubber, got it hooked up and working bu made no more power than petrol because the injectors ended up being wide open all the time as they couldn't supply enough fuel. With the amount of work reguired and other priorities at the time we gave up and went back to petrol.
Saab can get away with running E85 as obviously all their seals are compatible already. But they also have some amazing electronics. They actively vary the ignition timing in combination with measuring knock to get maximum power - hence they suit e85s resistance to knock out of the box. I was also told that Saabs don't use cam sensors as they measure the change in engine speed during cranking to detect the compression stroke (Aprilia do something similar on some of their bikes).