got a compression tester, what size adapter should i use on my 87 n/a
 

got this new compression tester..... :)
it has a 2 different sized adapters 14mm and 18mm
will either one of these fit my plug holes???

it is made by actron, i got it from advance auto parts...
anyone use this one before?

opps, did i mention once, i open the package, i can't return it........

not really sure on the size but if u have a old plug hold the threads of the plug on the side of the tester threads and if they match and the diameter is the same u r in luck, or u could just try to screw it in the top left t-1 it is the easiest to get to. make sure the wires and plugs go back right or it will run like a-- your plug wires should be 2 black boots with one marked these will be L1 and L2 the other blue boots t1 and t2 the coils are the one closest to the front of the car is the leading should be marked L1 and L2 the one next to the firewall is the trailing also marked t1 and t2 they go like this top left t1 / top right t2 / bottom left L1 / bottom right L2 / plugs are marked too good way to remember T=top L=lower hope this helps PEACE ex...