compression ratio April 02, 2009, 02:07:39 PM compression ratio for the 3.8L stock. building a twin turbo setup for my car and need some info. ant any one know the optimal ratio. any help would save me a lot of time and headaches. Quote Selected
compression ratio Reply #1 – April 02, 2009, 02:26:46 PM I would recommend using a stock Supercoupe engine as a starting point seeing as they have better internals from what I have been told and if you use lower compression your turbos will be happier. Boosted applications seem to enjoy lower compression. Make sure you do your homework I was going to do a twin turbo V8 on mine but have somewhat changed my mind because of how difficult it can be. Quote Selected
compression ratio Reply #2 – April 02, 2009, 03:01:42 PM 8.0:1 On the low side 9.0:1 on the higher side.86xr7 hit it on the nose though,use the sc engine as a starting point.The stock 3.8l internals won't handle much boost,especially twin turbo boost. Quote Selected