2
votes
2answers
3k views

Audi a4 2007 2.0T boosts but poor performance, fuel economy

My 80,000 mile 2.0TFSI Turbo Audi has lost a lot of performance but no check-engine-light (CEL) or codes. One month ago an independent garage looked at it and did $2200 of work including transmission ...
13
votes
3answers
3k views

Static vs. Effective compression: Why does higher effective compression not require higher octane gas?

Background I've been trying to do a lot of research on boost lately because I'm planning on running a moderate turbo setup on my daily/light-duty-autox car in the future. I'm trying to get into the ...