Hey guys,
Been a while since I have been on the site. Getting ready to pull my 350 and drop in the 455 I have on the stand. Looking for input if it is overkill to put in the 4 core support or not? I am doing the front and rear suspension at the same time so the front clip off would be easier if I went that route. I want to make sure i have the parts list needed along with the time and budget to get it back on the road for summer

Also need input on leaving the th350 trans in place atleast for the time being. The rear is non posi and thats a project for another time to make sure i stay on budget. I know i will have rework to do the th400 and rear in later but atleast motor is in and i dont have to worry about the driveline and kickdown pedal switch.

If i get the 455 mounts will i still need the notched valve covers? What else may come up? What about header clearance if i dont go factory manifolds?

Looking for these parts
455 frame mounts
Hood hinges
4core top plate
455 manifolds
Thanks,
John

 

Use the 350 mounts. 455 frame/motor mounts or 350 frame/motor mounts will be the same. The 455 is taller. If you go four core you also need to change the radiator top plate and lower saddles. I would stick with the 3 core unless you need to replace it.

 

I have a pair of hinges,sent pm

 

I asked the same question a couple months ago. Many opinions, but from what I get, unless you're in a very hot part of the country or if the old core is in bad shape, see how it acts. Check out the thread below.

George

https://classicoldsmobile.com/forums...rovements.html

 

Must be that time again...

Using either you existing frame mounts with the matching Anchor 2261 motor mounts or the 69-72 BBO frame mounts with Anchor 2328 motor mounts will put the crank centerline in EXACTLY the same place. Personally I wouldn't waste the money or time to swap the frame mounts.

As noted, the 455 is about an inch taller than the 350, so it WILL sit higher, no matter which motor and frame mount combo you use. Since the crank centerline is in the exact same place either way, header fitment is unchanged from a factory 455 installation. The notched covers are not mandatory either way, but the do make removal and installation easier with power brakes and A/C.

 

I don't think you can ever be to big on a cooling system, when you are stuck in traffic you be glad you have it. I don't understand why anyone would trust a new engine to a 40 year old cooling system.
Be real easy on that old drive train it won't last long behind a 455.

 

Thanks guys,
Jag. Not looking to keep the cooling system stock, just if swapping the whole core support is needed or not. I should have been more clear. My th350 is rebuilt and that's why I am pondering keeping it in with the stock rear untill I find a posi unit.

Would I be better off using a stock four core radiator and top plate or an aluminum 2 core that will fit the 3 core top plate and bottom mounts?

 

You'll love the 455. The th350 won't, unless its built.
I did that in a 73 cutlass years ago,(455/th350) it lasted 2 days.
If you keep your foot right out of it it should be ok....


Enjoy the new engine, Keep a good cooling system, you want to keep that bbo cool as it helps cool the engine oil as well. Overheated oil means damaged bearings etc.

 

I have a mild 455 E head build with no A/C and I run a $135 single core aluminum radiator with a shroud and it never goes over 180° idling at over 100° out

 

Ally, are you using the stock shroud?

 

Yes, I've got the fan shimmed into the shroud with a spacer about a 1/2" more than stock.

 

were did u get the 455 out of?

 

The front drive brackets will bolt on with the exception of the power steering pump. You can un bolt the lower mount from the upper and bolt it into place, then fabricate a spacer to make up the difference. This is due to the 455s taller block.