Running gas, a 50-200 hit is really nothing as long as there are good parts in the motor and marginal if its a bone stock w/ the 200. (good head gaskets are a must) that unless you already have a EGT setup, its not nesasary. Guessing if you car weighs 1700# and running mid 9's, a 150hit will lower your ET 1 sec. Different manuf offer different probes and attachments. some its a SS npt bung welded, some is a propritary fitting, and Ive seen a probe attached to a hoseclamp so just a .250 hole in the header is all thats needed
Check with who's group you run with as some Nostalgia groups do not allow NOS.
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