Acceptable Internal Modifications For Restorations.......

[Hrdly-Dangrs]

Can someone tell me the AMCA acceptable modifications (internal) for improving the performance/longevity of an otherwise 'Stock' motor in a 'Stock' Restoration?..... ....HrdlyDangrs

[k.perry]

Well I'll take a stab at the common sense approach and say anything bored over 0.070" on a 74" Big Twin is outlaw, since that is the OEM manual limit. Whatever the OE manual says for 61 & 74" is law, but you don't see many people being requested to pull their heads during judging, so how you gonna know?

[Carl N. Olsen]

You can have any modification that is not externally visible including coated pistons, unleaded valve conversions, balancing, even stroker kits. One thing to keep in mind however is that you must keep the carburator, air cleaner, and fuel lines correct for year model as there are catagories for them on the judging sheet. Every nut, bolt, washer, and engine componet must be correct on the exterior, but the judges cannot look inside to see what is going on. Also it is very important to have the engine capable of starting and running as you will probably be asked to fire it up to enter the judging area. Plating such as cadium, chrome, and parkerizing are also important, so do your homework.
Carl N. Olsen