Author Topic: 455 block  (Read 1311 times)


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455 block
« on: February 03, 2019, 06:20:29 PM »
I have a 76 trans am I am looking for a 75-76 500813 block.car currently has a 70 455 lower end with a set of 96 d port heads. Just trying to put the car back close to original as I can get.


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Re: 455 block
« Reply #1 on: February 06, 2019, 06:45:51 PM »
I have a 500813 block. But it's in my bracket racer, with 6x-8 heads on it. It's the only one I've ever run across. Don't think they made very many of those blocks.

Since you usually can't see the block casting number or date code, but CAN sometimes see the block code, if you can't find a 500813 block, you might wanna consider another engine which has the correct code for a '76 455. Do you know the exact block code that would have come in your car ? Or, could it have been more than one.

You can plug in 1976 455 & see all the codes that were used in '76. Then, you can plug in the code you want, and see all the engines from other years that used that same code. I noticed that a couple of '74 455's used the same code as a '76 code. There were also some 400 blocks that used some of the same codes. You could possibly use one of the 481988 400 blocks, with the correct code, and build it up as a stroker, with stock 455 stroke or 4.25 stroke. No, all the numbers wouldn't match. But, the only one you can see, when glancing under the hood, will match.


I have never seen any 6X heads that originally came on a 455. But, they are listed for some '76 455's. So, you could use some 6x-8 heads &  most would never know the difference. Or, you could try to find some 6H heads I suppose. But, the '76 455 heads had huge chambers, which made only around 7.6 CR. So, unless you don't really care about power, you'd probably like the 6x-8 heads better. 

The '76 Q-jet intake should be easy to find. Most D-port 350's, 400's, & 455's used the same Q-jet intake during a model year. All Q-jet equipped 350, 400 & 455 engines used the #525355 Q-jet, in '76. 350's & 400's also used this intake in '77. But, I assume that most of those used in '77 model cars, may have a date code later than the production date of your '76.


« Last Edit: February 06, 2019, 07:04:10 PM by oldskool »


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Re: 455 block
« Reply #2 on: March 05, 2019, 08:53:46 PM »
I have a '75-76 trans am 4 speed code 455 block I picked up as a core to build- My car is a '75, but an original 400 car so I could start with any 455 block. I also have the 4 speed bellhousing and flywheel. Only thing is, I don't know where you're located- I'm in Kelowna B.C. Canada.

Re: 455 block
« Reply #2 on: March 05, 2019, 08:53:46 PM »
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