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Rick Armour
Rick Armour, Technician
Category: Classic Car
Satisfied Customers: 387
Experience:  36 years building autos,from '30 Whippets to '60's and '70's Vettes and Mopars
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What is the difference between a truck 427 tall deck and a

This answer was rated:

What is the difference between a truck 427 tall deck and a 427 standard deck and what would I have to do to make it a high performance engine and fit in my 66 impala

You would have to significantly cut the deck down ( .400 ) to make a tall deck fit in your car. It is for this reason I would not recommend the swap.


The difference is deck height, intake, distributor, and the tall decks came with 4 ring pistons. Heads, crank, cam, rods, etc etc will interchange. The intake will not interchange.


If the height of the tall deck is no concern , add a 4.25 stroke crank, 6.385 rods, the "regular" 454 pistons of your choice, and cut about .050 off the deck. Simple, cheap and easy 496.


Good luck with your muscle, Rick

Customer: replied 8 years ago.
Are you saying I would not be able to close the hood with the tall deck and what do you mean about interchange, interchange with what, a standard 427 or 454 block?

The interchange was discussing your question of the differences between the two 427's. I only put in the 454 information on the pistons because you had asked about adding muscle to the 427 tall deck.

It's not the hood that is the reason most people have opted not to use the tall deck. The major reason is the modifications to the firewall. You will have too alter your firewall to make it fit.

Hope this helps, Rick

Customer: replied 8 years ago.
How much modifications are you talking about? I am in the process of a frame of restoration on this 66 SS Impala which is off the frame now and I got this tall deck that runs for next to nothing. What about the frame and engine motor mounts, would they have to be changed also, came with a small block.

Your big block will fit right into your frame ( same mounting holes ) I would use the small block motor mounts as they are a lower profile.

As far as using the 427 you have, I say GO FOR IT !

It will be tight, but, you can make it work.

Best wishes, Rick

Rick Armour, Technician
Category: Classic Car
Satisfied Customers: 387
Experience: 36 years building autos,from '30 Whippets to '60's and '70's Vettes and Mopars
Rick Armour and other Classic Car Specialists are ready to help you
Customer: replied 8 years ago.
What about the bell housing and fly wheel? This is a four speed car, will they transfer too. Also, will an of the shelf 454 crank and rods like you mentioned fit this 427 are they the same and what about a mild cam, lifters and will it run on pump gas?

Hello again,

All 396,427, and 454 parts are iterchangable, except for the above mentioned 427 tall deck parts. Your heads will need hardened seats to withstand the unleaded gas. A mild cam is always a performance adding modification. Using the 454 crank will work, but the rods will need to be 'tall deck' if you don't do any deck shaving.

There are many more factors on this swap :

exhaust ?

driveshaft ?

wiring ?

linkages ?

trans mount ?

As I am more of a restoraton expert, and not a modification expert I will 'opt-out' to another expert who might be able to help you with the rest of your questions about the unique way you are rebuilding your great classic car.

I am sending in a request for a refund on your accept, and will send you to well qualified hands.

Wishing you well, Rick


hi there my name is don i will be able to help you with your 427

i will assist rick in this

you have a few questions

i see and i am trying to read what is already there

you mentioned the fly wheel and bell housing

bolting up what are they from

please let me know