4.3 v6 to small block 350?

[kustomss]

I have a 1985 Monte Carlo with the 4.3L but I want to put in a 350. I know I need to change the x-member, motor mounts, etc. but do I need to change out the radiator? I plan to drive it in the summer when it's from 85-100 degrees. If I do need a different radiator, what one should I get? One form an SS or an aluminum one?

 

[Jg85350Regal]

I got one for an ss with ho 305 a/c heavy duty cooling when I did my 350 and have been fine. It was cheap too like 85 bucks iirc. The 4.3 rad may not be any different then the 305 though so I suppose you could run it and watch the gauge closely to see if its enough.

 

[KrisW]

If you have the radiator for the 4.3 with AC I bet it will be fine.

The crossmember is different? I wasn't aware of that. I have only had to change where the motor mounts were bolted to the frame and then I was good to go.

Good luck.

 

[Jg85350Regal]

I think we had to move my crossmember back but there was already another set of holes in the frame it bolted up to.

 

[jrm81bu]

As long as you are using the same transmission there is no need to move or get a different crossmember. Unless you are looking for a double hump one.

 

[kustomss]

My car is weird, it's a southern car but it doesn't have A/C. And I was only going to change the x-member if I change it to a turbo 350, but I'll leave the 200r in it for now.