Hi,
i have a savage x and i took the pull start off of it, anyways i cant find a back plate for a nova race 4.6 big block. I have tried to change it and it is not working. My dad called hpi and he was wanting to know if the part he was putting on was right. And they said yes and it is the right part .[:@] PLEASE HELP Thankyou. savycharlie And also the one way bearing doesnt fit either.

Please explane a bit more. Your tring to mount up another part? Not an HPI part?

If your changing a backplate on a HPI 4.6 you need to read the manual. There are some instructions for doing this, unlike other engines, you MUST have the piston at TDC on the stroke when inserting the backplate into the block.
Also use some sealer to insure aginst air leak.

Your one way issue is kinda odd. If your using the stock one-way shaft then you shouldnt have a problem with the oneway itself not sliding onto the shaft.

If your going to a "race" backplate with no pullstart or anything, then do you really need the one way inside there?