Decide what HP level you want and what the purpose of the truck will be. Towing, street, street strip, strip only trailer queen fairground cruiser. and buy your parts accordingly.
sweep the floors, dust the shelves etc in your assembly area.. this is critical.
The basics:
you will first need to take the block down and have it hot tanked. then have them magnaflux it to check for cracks. if its a good one, have them mic the bores to see what oversize it is (or look at the old piston, it may be stamped .030, .040 etc" .
Then depending on what you are going to do... (make a lot of HP, RPM and squeeze) you may want to have it sonic tested to check for core shift, runout, and ensure there is good meat in the cylinders for another oversize bore.
get it bored whatever the next oversize is but i would not recommend more than .040" you can go .060 but thats really pushing it as far as cylinder wall thickness. get it bored but DO NOT get a final hone on it until you get your pistons and are able to measure piston to wall clearances. You will be doing the final hone to obtain the proper piston to wall clearance.
get a crank from a 400 sbc motor (dont know the casting numbers off the top of my head) and have the mains turned down to fit the a 350 block. Remember that 400sbc's only came with a cast crank. They are beefier than a 350 crank but its still a cast. The should be able to handle up to 600 hp normally aspirated HP according to some. I thinkk with a 1piece rear main you will end up having to go with an aftermarket though. VERY IMPORTANT: have your entire rotating assembly BALANCED.
anyway, you can also get a Scat cast steel crank for a decent price these days. Do yourself a favor and toss the 400 5.56" rods in the trash or use them for paper weights or something. use no less than a 5.7 rod but preferrably a 6". various aftermarket steel rods like Crower, are really nice but a bowtie rod will do also. if you use a factory 5.7 x or o rod is the stronger one. have it shot peened or better yet, polished so the stress risers are removed. Important: install a GOOD set of ARP rod bolts.
drop the bearings in and installt he crank using Plastigauge to do the clearances on main bearings. avoid cranking the motor over while these bearings are dry! Mark all of your bearings with a sharpie so you know which journal it goes back into.
for street use, a moly top ring and an iron second ring is fine. insert them into the bore and use a squaring tool or an old piston to get them in there even. take a flat feeler gauge and measure the gap and make sure its where it should be. if it needs more gap then use a ring filer. if it needs less gap then swap it to another bore and see if it fits in there better, once you get all your rings swapped around and get the right gaps, make sure you mark them all so they all go back into the same hole during final assembly.
get some good pistons like JE's or SRP, ROSS or something like that. KB hypeuretectics are ok but remember that is still a cast piston and some of them have a hollow dome. decide what compression you want and what heads you will use and buy the piston. have the pistons professionally installed on the rod unless you are going full floater then its easy as putting on a snap ring. take the piston and rod and decide which bore each one will live in. stamp the rod with 1-8 so you know which one is which during assembly. you will have to drop the piston and rods into the bore and use a round feeler gauge to check piston to cylinder wall clearance. also install your rod bearings at this time. use plastigauge again to measure the clearances and swap bearings around if necessary to get the right clearance. Square the piston with a squaring tool or an old piston and measure. use the #1 stamped piston in bore #1 and #2 for #2 etc. as the piston and bores will all be different.
select your camshaft. remember bigger is not always better when it comes to cam and compression. you can make 500hp from a 9.5:1 383. also remember that the bigger the cam overlap the less dynamic compression you willl have due to the cylinder pressure being bled off during that brief moment that the intake and exhaust valves are both open.
Some people prefer to install the cam first but some say you should install the crank, rods and pistons first and cam last. there will be clearance issues in your block since it was not meant to have a 3.75" stroke in it. the clearance problem will be with the rods and the bottom of the cylinder and the rods to cam . you will have to go in with a die grinder and rotary rasp or something and clearance the bottom of the cylinder and possibly part of the rod bolt. as far as the cam to rod clearance, for smaller hydraulic and solids it will be ok if you use a 110degree lobe center or tighter and it should clear but you should check this anyway. preferrably you will want to buy a small base circle or "stroker" cam shaft. a cheap tool to clearance these areas is a medium sized zip tie as they are about .020" thick...... After you get all your clearances taken care of and you are ready for final assembly, thoroughly wash the block with Tide and water and a scotch brite pad. get some engine brushes and clean all the little holes and orfices. be VERY thorough. once clean, uses lots of assembly lube on the cam and the rod bearings. one of the last things you will be doing is Degree in the cam.... once the timing chain is in, get a crank turning tool and give it a crank and check clearances 1 last time. if everything checks out, then bolt your oil pump, pan, heads and valve train on and fly it. make sure you break the cam in correctly. 2500 rpm for about 20 min on hydraulic an solids. rollers dont need break in. Ok I am tired of typing.. but that shoud get you basically whats entailed. I'm sure there is some stuff I missed but this is the basics. If you have any reservations about doing this... TAKE IT TO A PROFESSIONAL to be assembled. theres nothing worse than getting a $$$ motor together and having it burn up or worse yet, break a cam or rod after a few miles on the street good luck.
in case you cant tell... its boring here at work today.
Last edited by LUVSADRAG on Fri Aug 08, 2003 4:00 pm, edited 1 time in total.
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