Thread: 1975 454?

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I just picked up a 1970 Monte with a 454 in it. Was told it's a '75. I'm assuming the casting numbers for the heads are under the valve covers like a small block but I was wondering if the block numbers are on the bellhousing like a small block also?

left side on block

By 1975, there were no performance parts on those 454 motors. I just picked one up for my Chevelle, it has a fresh rebuild in it, but its a daily driver. 8.25-1 compression with the small port truck heads. The guy did however put in an Rv type cam and a double roller timing chain. i added a wiend Stealth dual plane intake a set of headers and a 750 vac holley. See what i get out of it. as long as i have passing power on the highway i will be happy.

I'm wondering what this motor come out of myself. It has an Edelbrock intake and a spreadbore Holley. I just put new plugs, cap, and rotor in it and it's running alot better. I can tell it has a mild cam in it. When I drove it home it was running like crap and still would bark the tires going into second gear. Valves need adjusting but I'm thinking of swapping the cam out to a new Comp stick. I'll wait till spring and figure out what I'm going to do.

Keep us posted MRBIGG. I too have a newer 454 (out of a tow truck) that has a fresh rebuild on it. I am going to drop it into my 60 BleAir, but might throw a cam similar to yours before I do. Will also add headers , intake and carb as well. I am anxious to see how it will run.

Here is a site to check your numbers against...
http://www.nastyz28.com/bbcmenu.html
It will get you in the ballpark.

Thanks for the link. Here's what the heads are-3904390 1966-67 396/427 Closed . 325, 350 L-34/L-35 390, 400, L-36/L-68 98.4cc. Are these heads decent?

Couldn't read the bellhousing numbers but I found the numbers on the passenger side of the block, under the alternator. That number is T1100CXX, plus some smaller numbers. Can the block be identified with this number?