The previous owner of my car an '89 GTA with the L98, claimed to have rebuilt the engine (don't know how long ago) before I bought it from him. That bieng said, it didn't seem like he had rebuilt it because it didn't run at its peak when I drove it; a little sluggish actually. Turns out I needed another rebuild since only some of the parts we're replaced. Now my question is, if it was rebuilt a 1st time by the previous owner, meaning cubic inches we're increased a bit and then a 2nd rebuild under my possesion does that mean thats its not a 350 c.i. engine anymore and could possible be a 355? I'm just curious! Thanks in advance for any info

phoenix

 

A 350 bored out .030" makes it a 355. A rebuild doesn't always require an overbore. The cylinders only need to be bored out to the next over size if they're worn enough that they're not round. The forces on the piston by the con rod will eventually make the cylinder slightly oval.

If the cylinder bore is still in good condition, a deglazing and new rings is enough.

Depending what parts were replaced, new rings may not even be required unless they're damaged or have high mileage on them.

 

Right! Thanks for the info man . I actually have no idea as to how much it was bored out if any. Probably not much. Anyway thanks for clearing that up bro. Take it easy.

Later,
Phoenix