Best(Most Effecient Upgrades) and Tuning Tips?

I got into Forza earlier this year by playing around in Forza 4 back on my old 360. I’ve recently made the transition to next gen and I’ve started playing Forza Horizon 2. I was just wondering on the opinions on what are the best upgrades for cars and some tuning tips(How to set rollbars,differentials,weight distribution, etc.) since I’ve had an issue finding info.

There is some info in this thread http://forums.forza.net/turn10_postst28102_When-it-comes-to-tuning--I-m-an-idiot.aspx

I posted my build tips in there.

^^^what he said…
take the advises,he is a great tuner and he knows what to do…