heads on hot rod vw

i have a 356 speedster kit, and it has a hot rod motor, and i would like to know if i canuse long reach plugs the numbers are 041-101-375-2 2br 81 these numbers are on the heads,right now i have short reach plugs and they are fouling out,also i would like to know what the valve setings would be i have chromemoly push rods with hi perf.rockers with swivel ball adj.i am a new member thank you.

With a piece of wire measure the plug hole depth and use that plug length. Plug fouling is caused be a rich fuel mixture i.e incomplete burn, misfiring etc.
Moly push rods can be set at zero lash but you do leave enough to be able to freely spin the rod between your thumb and index finger...just be sure you have moly rods to do this. ~Alan

Yeah, check your push rods with a small magnet to see if it "sticks". If not, you have aluminum push rods which should NOT be set at zero clearance cold, but at .004" intake and .006 Exhaust.

gn

As Alan said, use only the correct length of spark plugs. You don't want threads from the plug protruding into the combustion chamber, only the electrode.

You've indicated that you have a "hot rod" engine and it's fouling plugs. First of all, what brand of plugs are you using and what's the heat range? A little more detail regarding your engine is needed such as cam?, displacement, carb/s manifolds, distributor, etc.

AS indicated, the most usual culprit of fouling plugs is jetting, second is improper heat range of the spark plugs. This is predicated on a 'tight' engine, (good rings, good valve guides, good valves etc)

Finally, list where you live as a knowledgable member may live close and can help you diagnose your problems.

Finally, look at the links across the top row and find "Knowledge"
Once there, locate #206 and it will explain how to adjust your valves.