My 327 Chevy engine was running well, but I noticed that the fuel pump had a
> small leak, so I installed a new fuel pump. After installing the fuel pump
> and cranking her up, the motor was shuddering like crazy, but then smoothed
> out, however the shuddering resumed as soon as I put it in a foward gear. I
> reinstalled the old pump but the engine is still shuddering. The wierd
> thing about this problem is that the engine will idle fine and will move in
> reverse gear with no problem, but as soon as I put it in a foward gear, it
> shudders and stumbles wildly. If I put it back in neutral it idles fine, and
> I can rev the engine way up without any problem.
>
> So far I have installed a carb kit (Edelbrock 600) and installed new spark
> plugs but still have the exact same stumbling and stalling problem when
> foward gear is engaged. This thing has me mystified and I really would
> appreciate any ideas anyone might have as to the possible source of this
> problem. (Tranny is a 350TH).
>
> Thanks in advance for any advice.
>
>
The cheapest/simplest thing that comes to mind and just a wild guess, as learned from past work on hot rods: Check the transmission-to-engine bolts. I've seen them work loose and cause the symptoms you mention. It does not sound like it has anything to do with the fuel pump, but just a coincidence it happened right after you changed it. HTH, s