1997 engine swap (4.3L v6 to 5.7L v8)

[mountie1982]

I am toying with the idea to swap out my 4.3L v6 to a new 5.7L v8. I have a spare chevy 350 that has been rebuilt sitting in my shop. It was a spare engine for one of my many trans ams. I looked for other posts about the swap but nothing really tells me too much about it. I am not looking to put in a high performance engine just a stock 350. I just want to know if anyone has done this and how much of a pain in the arse was it to do. Can I use the same mounts or are new ones needed to be welded in? Can the orginal tranny from the 4.3L hook up to the new 350? Can the drive tran take the power of the 350? Like I said its not much better then a plain stock 350. My blazer is 1997 4x4 2door with a 4.3L v6


Thanks

[BlazerLT]

Need more information about the 350.

[mike2004tct]

Blocks are different, so modified mounts will be needed.
Bell housing mounts/transmission cases are different, so the original
tranny won't fit the 350 SB.
The rest of the drive train can handle the extra torque of the 350. A stock SB only has perhaps 20-40 more HP/torque. (My '85 L98 350 is rated at 230hp)

I have no experience with this personally, but I did see a couple of these combinations last year at the Jefferson swap meet . One truck had the motor in the normal location, the other had the motor in the cargo compartment.

[BlazerLT]

It all depends on the year of the engine.

It could bolt right up to a 4,3L.