omy442

Sorting the 66-67 Olds parts collection continues.

Included in the 66-67 Olds parts collection, were a set of new Jahns Pistons.

Unfortunately the box label was missing part number. I'm guessing it's from the 70's based on age of box and shipping label typewriter font.

Did some research and back in the day Jahns was a no frills budget piston.

Didn't see any part number inside the piston only the name.

I can have a machine shop micrometer size, but not sure if that will help identifying what they are.

I found them next to a set of standard Oldsmobiling 350 Pistons and rings.


Mader
jm68442@yahoo.com

Fun71

The piston diameter and pin height (compression height) will really help. Also the dish volume, if they are dished - can't tell from the pictures as the pistons are wrapped.

66-3X2 442

350 pistons are commonly used in 65-67 400 engines.

BillK

Actually Jahns was one of the early race piston manufacturers and as far as I now they were very good for their time, certainly "not no frills budget"

If your machine shop can measure the piston diameter and the pin height that is all you need to properly identify them. They almost look to me like they have a small dome on them. Hard to tell for sure by the picture. Are you certain there are no numbers on the pistons anywhere ?

What is on the label where you have it blacked out ??

omy442

I blacked out the ship to address.

I'll have to dig out the piston tote.

The wrappings disintegrated on the one I looked at, put it back in box then snapped a pic.

Pins are pressed in, but Pistons have been sitting for a long time.



Mader

66-3X2 442

I bet the pins are just stuck,pins press into the rod,not the pistons.

BillK

Exactly. What I have found is running under real hot water will expand the piston enough to get the pins to move. Once you get them free a little CRC or WD40 will free them up.

omy442

I'll just have to make time to visit my machine shop and get Pistons measured.

I'm curious to know what they are.....

Mader

Tedd Thompson

Can't the box with UPC number be run, and the information found, I know on hardware each product has its own UPC number...Tedd

BillK

Pretty sure the Jahns pistons are from a time before bar codes existed, or right about when they first came out

omy442

Box appears to be from early 70s with manual typewriter shipping label... before barcodes and upc's.

I'll take to machine shop to get measurements.

Mader

omy442

6.15 update

While loading totes into trailer for homecoming, I looked again at box and other end had part number.
I called JE Automotive but their records didn't go that far back.

It's part number 8-1156 H RP
.60 over with 13:1 compression ratio with 1/8 dome.

I'll search later.
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Mader

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v8al

I found this on the internet supposedly from a 1969 Jahns catalog. Maybe someone has an old catalog and confirm.

1965-67 400 &425 Bore sizes 4", 4.057, 4 1/8 flat top is #1156

omy442

Thanks for the info !

redoldsman

I can remember Jahns being the piston most hot rodders used back in the 60's. They were known as premium stuff.