I am having my LT4 heads worked right now and the machine shop that is doing the work says that I can't go with 2.02/1.60 valves without putting in oversized seats. I spoke with Mike at MORE performance and he says that he does it all the time. My question for you guys is, when you had your heads done, did you put oversized valve seats or did you not worry about it. The machine shop says that I could forego the valve seats but that the valves will start wearing on the seals in a week or so.

 

the intake seat is no problem at all.the exhaust seat is a toss up.they are so close the being too small for 160 exhaust valve that i replaced them,but it can be done.if you can swing the price i personally would replace atleast the exhaust seats,but if not it will be ok.

 

you can just cut the seats for the biggest valve possible(near the edge) and then stick 2.02/1.60s in it.. but it won't be OPTIMUM, ie.. a 2.00/1.56 on the same seats will out flow the bigger valves!

 

Thanks for the replies. If there's no ill side effects, then I'll go ahead and have the oversized seats installed.
CHris