Sorry but when it comes to RX7's I am a purist and do not like the V8 swaps. If it was me I would do some searches for 2 and 3 rotor setups. There are several companies out there that will do this for you. You can make a lot of power with the rotaries naturally aspirated which is my preferred method for them as well. The 13b is hell of an engine so don't under estimate it.
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