I have an lsv with:
b18a1 bottom end
eagle h beams
Wiseco 13:1 pistons 81.5mm
Gsr head
Skunk2 pro3s and lmas
Supertech valves, dual springs, retainers

I do not have any ptv clearance issues however my pistons keep touching spark plugs. The R5671A-8 ngk plugs recommended on the 'how to build a reliable lsv' thread were bumped closed causing misfire, did not break the plug or damage piston. I bought BKR6E stock gsr plugs only to find they were the same length. I called ngk and they said I had to run race plugs with a retracted tip that were $40ea and track use only. I have a different daily driver but the car does see the road so I'm looking for a reliable plug that will not cause clearance issues. What is everyone else running? Thanks in advance!

 

You must have that head milled or block decked quite a bit to run into that issue. MANY people run those pistons w/o any clearance issues. That is if its the same piston everone else has been using. The piston has to damn near be out of the hole, not just the dome. I bet you're well above 13:1 compression. Have you taken and comp tests to get base numbers? How tight are you putting the plugs in the holes?

This just isn't a common issues which is what I'm basing my statements off of.

 

yeah seems like something else is going on here. did you clay the motor to ensure no ptv issues? what headgasket/thickness are you using? if its that bad hitting the spark plug id almost be concerned with piston to head at high rpm. whole thing kinda reminds me of muckmans high comp boost build...

 

I did not clay the engine, I bought the lsv already assembled, tore it down for new rings and bearings, and used a golden eagle 81.5mm headgasket. Is there a Spec for height of the gsr head? I am unsure of whether or not the previous owner had the block decked or head milled.

 

civics4lyfe if you are bending the strap on a non projected tip spark plug like an NGK R5671A-8 (which is a race plug btw) then your pistons are entirely too close to the head.

If you are using a stock style 0.026"-0.028" compressed thickness headgasket I would strongly suggest going to a 0.060" thick headgasket since this is easiest way to space the head/sparkplugs away from the pistons.

The alternative is to dissassemble the engine and have a machine shop mill a bit off the top of the pistons for more clearance. Or you could buy different pistons.