Jump to content
HybridZ

crankshaft question


Recommended Posts

hi guys........my sbc has a standard size pistons. its going to a machine shop next week increasing the bore to +25..........will i need to replace the crank? what size pistons will i get? the piston rods looked to be in good shape, can i still keep use them? appreciate the help guys.

 

-thanks-

john

Link to comment
Share on other sites

Hmmmm...I think that before you do anything else, you should get a couple of books on rebuilding SBC engines. Your questions are not very lucid. Look in the Summit Racing catalogue and there are some good ones, esp. the one by the late John Lingenfelter.

 

But, in answer to your questions, the bore size has next to nothing to do with the crank shaft. 2nd, inorder for the machine shop to bore your block, they will need the pistons, so you will have to buy those first.

I would suggest that you remove everything from the block, and take the block and the crank to the shop. Ask them to inspect and measure the crank to see if it needs to be cut, or if a polish on the journals will suffice.

Also ask them to measure and inspect the bores. They may need to bore it to the next oversize, in which case they can tell you which size pistons to buy, or they may be able to just clean it up with a hone job....and then tell you which pistons to buy.

Take the rods in too, and ask them to shot peen and magnaflux them, or just buy some new ones.....stock replacementr rods are cheap.....

Also, ask them to remove and replace the cam bearings...

Tim

Link to comment
Share on other sites

Grumpy and Tim are right. Vizard's "How to rebuild your SBC", and the first book in the link, "How to Hotrod your SBC", are excellent. You'll understand a lot more after reading them, and there's a lot of references about torques, torque patterns, etc., that are very useful.

 

John

Link to comment
Share on other sites

you need to buy and read at a ABSOLUTE MINIMUM books 3, 4,and 5 on the list

 

HOW TO BUILD MAX PERFORMANCE CHEVY SMALL BLOCKS ON A BUDGET by DAVID VIZARD

1884089348.01._PE30_PIdp-schmoo2,TopRight,7,-26_SCMZZZZZZZ_.jpg

.

JOHN LINGENFELTER on modifying small-block chevy engines

155788238X.01.TZZZZZZZ.jpg

 

how to build & modify CHEVROLET small-block V-8 CAMSHAFTS & VALVTRAINS BY DAVID VIZARD

 

SMOKEY YUNICK,S POWER SECRETS

0931472067.jpg

 

trust me it will be the best money you ever spend!!!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...