Truck2200

My Mother owned a 1971 or 1973 Oldsmobile Dynamic 88 in the early 70's. What I would like to know if anyone can verify the model and engine with the Olds history? What I remember is it was Two door, with a 425 Ultra High Compression (13.5-1) engine with a 2 barrel Carburator. In all my searches I can't find a listing for an Olds of this type. We lived in Houston at the time and I had recently gotten my Drivers license so I was able to drive the car several times. If you know anything about this car please let me know. Thanks

jaunty75

With good reason! There was no such car.

First, the "Dynamic 88" name was last used by Oldsmobile in 1964. After 1968, the only 88 name used was Delta 88, so if your mother owned a '71 or '73 Olds 88, it was a Delta 88 (or a Delta 88 Custom or Delta 88 Royale) and nothing else.

Second, the 425 V-8 was in use from 1965 through 1967, after which it was superseded by the 455. Two possibilities exist for the engine in your mother's car. It was either an Olds 350, which was the base engine, or the 455.

Third, I don't think any Olds engine ever had a compression ratio as high as 13.5 to 1. The highest compression ever offered by Olds was 10.5 to 1, I believe, while the "low" compression engines were 9 to 1.

Truck2200

Thanks for the comback. I will aknowledge(sp) that it cold be a different year, I'm not really sure. But I KNOW it was a 425ci with a 2 barrell carb and 13.5-1 compression ratio. All that information was on the air Cleaner cover. I have looked as various year pictures of the Dynamic 88 and I still haven't found the correct model. Do you know of a site that would have all the models from '61 through '73? Something else, My Mother sold the car and next got a Delta 88 with the same engine but with a 4 barrel carb, 2 years older. Thanks.

Truck2200

Nevermind the site. I found the model I've been looking for. It was 1965. Still haven't found the engine that I remember though. '65 may have been the last year instead of '64.

jaunty75

I did say something incorrect above. 1966 was the last year for the Dynamic 88, not '64.

If your mother's car had a 425 and it was a Dynamic 88, it had to be a '65 or a '66. As far as the air cleaner, Olds wrote the words "ultra high compression" on the air cleaner on their higher-compression engines, but the actual compression ratio itself was never written on an air cleaner. The compression ratio in the 425 high-compression version was 10.25 to 1. Olds didn't get to 10.5 to 1 until the 455 came out.

Below is the '66 Olds spec sheet. Note the compression ratios for the 425. Low was 9.0 to 1, while high was 10.25 to 1.

MDchanic

1965 sounds right, but you'll have a long search of you insist it was 13.5:1 compression, because Olds never made one.

The 425 your mother had was 10.25:1.

Welcome to ClassicOlds.

- Eric

edit: You got there first, Jaunty!

MDchanic

Except for the Toronado (and the 4-4-2, if you count the 400).

- Eric

Truck2200

Check out this site- http://www.ebay.com/itm/Oldsmobile-E...US_Cars_Trucks

MDchanic

Yup. That's a '65 Dynamic 88.

It looks like someone gave it a quick once over about ten years ago - no telling what's under that paint.

- Eric

jaunty75

You're right. I missed that at the top of the list. 10.5 to 1 for the Toronado engine. But nowhere was there ever 13.5 to 1.