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The 454 is a TRUCK engine. Neither a 454 nor a (Ford) 460 belonged in a CAR. Even so, it happened.

The 454 found its way into quite a few Chevy cars during the 70s straight from the factory. I at least recall Monte Carlo, Chevelle, Camaro, and Impala being optioned with that engine. Some may recall the 454 Chevelle LS6 being touted as one of the most powerful cars of the era with its massive Holley, solid lifters, 11:1 compression and functional ram air hood!!! Most truck small and big blocks had 4 bolt mains on the crank for strength as did the real high-po car versions. I'm not as familiar with Ford, but think the 460 was in some of the larger cars.

The 400 small block is a very stout engine. Being a siamesed cylinders gave more meat around the bores. The rest of the engine is tested and proved small block chevy. Heat problems came more from steam pockets at the head. A good freind of mine had over 175000 on his 77 400 in a 24' class C. never had any over heating problems, I would not let this 400 keep me from buying this coach. The 400 has more pull than the 350 with out the weight of a 454. Parts are everywhere and less expensive than any other powerplant.

Doorman

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Heat problems came more from steam pockets at the head.

The correct heads for a 400 Chevy had steam holes drilled in them. This was one of the things that made 400 heads unique although some guys took other SB Chevy heads and machined holes in them. The real issue with overheating was there is no water jacket between the cylinders on the interior of the block. This was not realy as much a typical overheating of the coolant problem, but was more related to the interior bores super-heating under stress as there was no coolant there to carry the heat away rapidly. This elongates the cylinder bores and was responsible for head gasket failures when the head didn't expand as much (it was cooled with water jacket properly).

This was a bad design no matter how long any particular engine lasts. I put it in the same box as the 3208 Cat. OK if babied, not so much if driven hard.

Well, there is another twist to this....


I called up a friend of mine who is restoring a 1972 Chevy Pickup. I asked him if there was a
"Chevy small block 400 and a big block 400"? HE said, yes and no. The big block 400 was actually 402 cubic inch although GM called it a 400 cubic inch engine.

Mercy, I should have taken long bits of copious notes....he knew his Chevy engines. At one time, I had a 1972 Chevy 3/4 ton that had a badge saying 8-400 on the sides of the front fenders. It had a "big block 400" although it was actually 402 cubic inches. He said, that if the pickup said 8-400 on the fender badge, you could open up the hood and look and if the valve covers looked like typical 350 v-8, it was a small block. If the valve covers were wide and flat, like a 454, it was a big block.

The friend told me that there were different small block versions, long and short stroke for cars and pickups. His dad had a 1972 Chevy Van with a 400 small block and it was one of his all time favorite and smoothest running engines. He told me that the reason for the 400 big block (aka 402), was a 1969 warehouse fire in the GM plant that built the 396 engine blocks. They had to use water to put it out. The result was many thousands of 396 blocks with slight rust in the bores. GM bored them out .030 and that was the 402.

K&E

Great story! I always thought of it as the 402, but I suppose in Alaska it started the day as a 398 and ended as a 405 due to expansion/comtraction

You may also not realize where the 427 and 454 originally came from....

Down here in the south, it gets so stinking hot that those 396 blocks would stretch out to a 427 or sometimes a 454....it finally dawned on GM that the southern cars were so much faster than northern cars that GM just went ahead and started boring them out from the factory like that.....so the Yankees could enjoy them too......

Ha! Ha!