[KingLT1]

Best mod on gen5 engines is a flex sensor and tune if you have E85 available in your area. Should be able to run close to full pump E on a stock car...as you do mods you will have to mix the E content down which doesn't cost much for power just adds the hassle of mixing. Long as you can run E40+ the benefits of E will out weigh the hassle of mixing. 50/50 mix of pump E85 and pump 93 will land around E52. The flex tune will make all the changes to the tune so all you have to do is fill it and monitor the E content to make sure the system doesn't have too much E in it.

Look at it like this...A cai, headers, tb, and 93 tune car will make the similar power(620-630whp) as running full pump E on a otherwise stock car. If you do flex fuel, headers, cai, ported tb, you will probably need to mix the 50/50 as I mentioned above.

The car will make more power consistently on E being it will be able to maintain full timing at higher Manifold temps and overall much more resistant to knock vs 93.