As I debate replacing my Cutlass's 350 with a 455, I keep hearing that '70 and older versions are MUCH better than 71 and newer 455s. Is it a lost cause to find a mid-70s 455 and put some earlier heads on it? I'm looking for mid 13s in the 1/4 mile and I DON'T want to have to bore an engine and/or put new pistons in it ($$$$). Which brings me to my next question; when did the 455 start getting pistons with a dish too deep to get decent compression without replacing said pistons? I'm looking for a compression ratio in the 9.5:1 neighbourhood (pump gas, no additives) when all is said and done.
Thanks!

- GoldOlds

 

I don't think breaking into the 13's requires higher compression on either a BBO, you can build the top end and with proper gearing it shouldn't be to hard. I rebuilt the 455 I am using on my project car and ran it in a '69 Delta for five years (heavy car). The car has a peg legged 2.73:1 ratio rear in it and the engine is bored over .030 for total compression ratio of 9.75:1 and runs on cheap fuel any day of the week. That car ran a best of 14.95 seconds in the quarter mile.

 

Why would you look for a 35 year old engine, that you do not know the history of, and run it hard to get into the 13's. Why not rebuild it now and have peace of mind. Who says you have to bore it, maybe a good scratch hone will do. Some KB hyper pistons a good cam, rings, rods and mains, oil pump and down the road.

All 68 -76 455 are good. 68 -72 have sallow and deep cup pistons. all 73 -76 have deep cups. 68 -72 heads are very good. 73 -76 heads can be made to work. All of them are good material.

I think for a few dollars, you can do reach your goal, you don't have to go wild with the money. Just a basic rebuild and peace of mind. Then run her hard.

Geno...

Also, you know you will need some decent gearing and converter and tires....

 

My Cutlass has a 12 bolt Chev posi rear with 3.73:1 gears; I don't want to go higher (numerically) than that. I could deal with a honing for the block. Right now, I'm pretty much stumped on what I'd do for a cam if I took the 455 route. How much lift/duration could a 9:1 455 with 3.73 gears handle and what stall speed would I need for the converter? I'm not even sure if I'd go hyd. roller or hyd. flat tappet; I like Comp, but they don't seem to offer much in the way of Olds hyd. roller cams... which might be just as well, since money IS an issue. On the other hand, I've heard MANY horror stories about flat tappet cams getting wiped out (especially Comps?) during break-in; hence the confusion. Any suggestions?
Thanks for the responses!

- GoldOlds

 

my 76 Cutlass runs a built 76 455 with 10:1 and 3.73 gears and I have no problems with performance. Heads were set up to handle comp cam and larger springs otherwise stock heads. The original 350 was slightly built and had no problems with times that you are looking at. 350 can be built with little work to perform great.

 

olds used basically the same piston on every olds ever made. you had the pre

 

if you arent looking for major machine work there basically isnt any difference
in olds pistons. they came in two versions in the 400/455 as well the 330/350.
high or low compression. directly connected to carburetion. 4 barrel or 2 barrel. where olds was able to effect horsepower was in the cam. .435 was
standard where a .472 went into high performance tornado and 442.

 

The cam in the engine I referred to had .498 lift on both sides using hydraulic lifters. Works fine for me.

 

I agree.

Except for material, dimensions, and manufacturing methods, they were identical, from 1897 to 2002.

In a given year, the difference, between the 9:1 and 10.5:1 advertised compression ratio, was determined by a carb change?

Norm

 

Small blocks had three versions of cast pistons, large dish/low compression, small dish/high compression, and flat top for W-31s.