i just bought a 400 small block. the main bearings were shot but im rebuilding it all anyways so i didnt think it would matter. anyways the main caps need alot of force to go into there slots on the block.

is this normal because i have a 350 also and the main caps just go in to the slots no problem. i was just wondering if my caps are shot. if so where can i get the front and back caps aftermarket? havent been able to find some because the 400 crank journal is larger than other small blocks.

thanks

 

Well, I've seen them a little tight before and it didn't cause any problems. Certainly, any block you can shove the main caps home by hand is too loose. Ideally, it should "suck down" into the saddles under slight wrench torque, however. If it's gorilla torque to get them down in their saddles, that's too much and you should get in touch with your machine shop. However, if they were that tight you woulda had a heck of a time getting them off in the first place.

I'm assuming you kept all the caps matched with the mains they came from and that you have them properly oriented (correct side facing forward). No weirdness or changes to parts- everything going back where it come from.

 

Agree with Damon, I've have to put some firm mallet pressure on BBC caps to seat them before torquing.

SBC caps seems to have less issue, not sure if it's my lack of engines, or the nature of the beast.

You should be able to pick up main caps almost anywhere...from high dollar splayed to stock...both would require to have the block align bored, I'd think.

 

the engine was already dissasemble when i got it but the caps are numbered/in order so i just thought i would ask, thanks for the info. im still cant decide if i should buidl my 4 bolt 350 block or this 400 block. lol dont ask why i just have bad feeling about the 400 for some reason. anyways thanks again