building a nailhead

[Duane Harr]

hi guys\

just joined looking for inside help on building a 401 nailhead.

Thanks

[Bob]

Welcome, I am going to be doing one soon too. Mine will be close to stock with some head work very mild cam and 2x4 set up. Working on the carb right now so I don't have to deal with them this fall.

[DocModisett]

OOOOK,,,, first , build the engine to stock buick clearances and specs.... dont try to build to loose tolerances.....
Do your homework,,, know your piston to valve clearances, deck heights,,, and dont line bore the mains,,, that puts slack in the timing chain that you cannot get out....
replace and ream the valve guides before you grind the valves, that way the seats will be coencceritic with the guides....
If you can afford them install forged pistons.... if not, good name brand cast will work fine .....
dont fail to install a new set of cam bearings,,,, dont let anybody talk you out of this,,,, if you dont , the oil pressure will suffer....
Tip, you can make a good cam bearing reamer out of a old cam by cutting a L shaped cut into the bearing surfaces of each bearing journal.... make the cut 'face' the right , that way you can turn the cutter with a wrench....

I use a good moly grease to lube the cam lobes and the lifter feet when putting a cam in... moly grease will not drip off the parts , no matter how long it is before start up...
on a stock engine the compression ratio will usually be a full point below the advertised c.r. .....
the oil pump/system is good as is....
If a engine aint clean enough to eat out of , it aint clean enough to put together....
Be sure to clean INSIDE the rocker arm shafts with a rifle brush and compressed air....
straight simple green is a very good cleaner for soaking crud off of parts,,, just submerge and soak for 24 hrs.... then rinse off with clear water and dry with compressed air....
When it comes time for start up,,, install the oil and zddp additive and then prime up the oil pump/system with a drill motor.... check the rocker arm oiling.... and install the dist into the engine....
after you get it running break it in by driving it 500 miles, changing the oil/filter , and then drive it another 500 miles and change the oil/filter,,,, each time you change the oil , add zddp,,,, and from then on every time you change oil and filter add zddp.... it is a must have....
from that point on , you can get on the engine without worrying about it....

[jims58buick]

Hi all I am redoing a 364 to stock looked in the book and it said that the spec for the bore is .0008 to .0014 this seems a little tight the motor guy wants to go no less the .002 and is looking to go .0025 let me know what it should be so I could tell him

thanks Jim

[Bob]

If you go to the chassis manual and read the "how" of the piston fitting, you will find that a .003" feeler guage is used on a pull scale to check for desired piston fit in the '57 manual. I expect the machinist is going to use a .002" feeler guage without a pull scale and will depend on his experience for fit.

I expect you will be happy letting him do it his way.

[jims58buick]

Bob thanks for the answer. I wanted to know if there would be a problem by not having the correct spec I trust the builder with this motor but he had questioned the spec in the book thinking it was a little tight and it could have been a miss print

[DocModisett]

Stick to stock buick clearances.....