Forgot to answer part 2 of your question. Porting will depend entirely on how well the original factory job was done. The biggest gains are in the valve job and the last 1/2" of the port where the head and seat meet. Sometimes it's really good and you'll only see 3-5% improvement. Sometimes it's really bad and you might see 10-12% improvement. Other times, the cores shift when the head is cast and the ports are so badly misaligned there is little you can do but find another head. I have seen this even on turbo Supra heads. Luckily, the head was getting bigger valves, so there was room to work the step out, but it was really close.Originally posted by Ryan'sTc@Feb 3 2005, 08:43 PM
Does anybody know a good shop in northern california that specializes in portting heads for the 2az-fe engine. Or has anybody already done this and if so how much of a difference has it made?