Help please 455 swap

[Sethj013]

I have a 85 cutlass supreme with a 3.8 v-6 and a turbo 350 I recently got a olds 455 engine what all do I need to make the swap from the 3.8 to the 455?

 

[dan2286]

Here you go, this pretty much has all the info you need.

http://www.robertpowersmotorsports.com/G-bodyV6-V8.html

 

[rccktmn2]

Are you planning on using the th350? If you are going to use the th350 then I would put the engine on the trans and bolt it in the car and see where you motor mounts are going to be on the frame and then bolt them down, I'm pretty sure they will be more forward on the frame than the 3.8 so you will have to move them. From there you will have to figure out which exhaust you want to use, either headers or dual exhaust manifolds, either one is not cheap, hooker, and dick miller both carry swap headers for this, if your going to use headers a dual hump crossmember would be helpful also, crossmembers.com has the crossmember for this as well as jegs and summit. From there you need to consider what accessories you want to keep, power steering, air conditioner, etc. This should be enough to get you started, the 455 will fit under the stock hood.

 

[joe_padavano]

Are you planning on using the th350? If you are going to use the th350 then I would put the engine on the trans and bolt it in the car and see where you motor mounts are going to be on the frame and then bolt them down, I'm pretty sure they will be more forward on the frame than the 3.8 so you will have to move them. From there you will have to figure out which exhaust you want to use, either headers or dual exhaust manifolds, either one is not cheap, hooker, and dick miller both carry swap headers for this, if your going to use headers a dual hump crossmember would be helpful also, crossmembers.com has the crossmember for this as well as jegs and summit. From there you need to consider what accessories you want to keep, power steering, air conditioner, etc. This should be enough to get you started, the 455 will fit under the stock hood.

Actually, you need the frame mounts for a 307 Olds, which bolt to the REARMOST holes in the crossmember. Note that these mounts are actually RH/LH, so you need to be sure they go on the correct sides. Use Anchor P/N 2838 motor mounts. DO NOT get "455" motor mounts. Use W/Z exhaust manifolds from a 1969-72 A-body.

 

[rccktmn2]

Are you planning on using the th350? If you are going to use the th350 then I would put the engine on the trans and bolt it in the car and see where you motor mounts are going to be on the frame and then bolt them down, I'm pretty sure they will be more forward on the frame than the 3.8 so you will have to move them. From there you will have to figure out which exhaust you want to use, either headers or dual exhaust manifolds, either one is not cheap, hooker, and dick miller both carry swap headers for this, if your going to use headers a dual hump crossmember would be helpful also, crossmembers.com has the crossmember for this as well as jegs and summit. From there you need to consider what accessories you want to keep, power steering, air conditioner, etc. This should be enough to get you started, the 455 will fit under the stock hood.

Actually, you need the frame mounts for a 307 Olds, which bolt to the REARMOST holes in the crossmember. Note that these mounts are actually RH/LH, so you need to be sure they go on the correct sides. Use Anchor P/N 2838 motor mounts. DO NOT get "455" motor mounts. Use W/Z exhaust manifolds from a 1969-72 A-body.

Yea your right Joe, I looked on mine and it is the very rear holes you need on the frame. I didn't use the 307 engine mounts though but I did make my own frame mounts so I'm sure there's a difference. 😀