[m6-lt1]

E85 is the best bang for the buck mod you can get on these cars. I think you possibly misinterpreted what you read since you said e85 by itself isn’t worth it. I think what you may have read was that it doesn’t make sense to only do one mod that requires a tune. If you’re gonna do additional mods that require a tube, it makes the most sense to do them all at once. If you only can do one mod though e85+tune is easily the best bang for the buck mod on LT1 powered cars.

Deleting the secondary cars aren’t going to gain you anything. I think you again misread something. Deleting the PRIMARY cats nets you a very similar gain to doing long tube headers. Headers still gain more but not that much more versus the cost of headers versus cat deletes.