904 lockup info

-
OK - I made a trip to my storage trailer today to look at my core lockup transmission. Turns out (according to Mr. Hand's book) it is a 998 out of a 1980 Chrysler. Just looking at it, it is Very similar in case/tailshaft housing dimension. This is as compared to a 1965 cableshift gearbox. Should fit right in the same space.
That being said, does anyone know if that particular breed of 904 have any particular problems? it's a 4130956. It should have a lot of the upgraded parts and a 4 disc front clutch retainer as well as the wide ratio gearset. (some of the early 998's even had 5 disc clutches - but that would be too much to ask for!)
While I was messing around, I pulled the cooler line fittings off and took a look down the outlet hole. It is quite close to .250" (sits back in there a ways and I didn't have my inside mic handy) So, now I am wondering, just Why would I need to have cooler lines any larger than that??? The inside diameter of the fittings (-4 to 1/8" pipe) is even smaller - around .228 at best. I pulled a stainless AN -4 to 1/4 pipe thread adapter out of my parts bin and even it was less than .250! So - what we have here is not one, but two flow restrictor orifices. Not gonna get much, if any, better flow with larger lines. (same volume, less velocity) That being said, I will still put -6 (3/8") lines to my cooler, just because it makes me feel better. And the guy you run over will say "Wow, look at those fancy cooler lines!"

Upon closer examination, the fittings on the transmission are std 1/4"flare fittings using a 90*/ 45* seating angle - AN fittings (at least the ones I grabbed) are 37*. Cheech14, Art, R/T
 
There is no issues between the various models.
Just what there built with inside.

Later years have bigger lines. Why they did this I’m not sure but it might have to do with the 904 variants (A-500) being installed in trucks. Those have the extra gear and have the potential of more weight when the truck is loaded. My 4X4 ‘03 quad cab Dakota wasn’t exactly light.

Makes sense. Heavier, taller gears = more heat. I'm betting those transmissions have larger passages to the cooler line ports also!
I am in the process of mourning for a friend who passed just about 48 hrs ago. Normally, I would not mess with posting something like that, but I have known him long enough that he was around when my Dad bought the Formula S - the one I am currently working on. We talked about it whenever we were together and he was looking forward to the completion of the car. We were going to take it cruising together, just like we did in the 60's & 70's. Unfortunately, that will not happen. His memory will be with me whenever I am in that car! Rest in Peace - my brother in cars, motorcycles, music and good times! (Oh, do I have some stories!) bye, Bruce.

Art, R/T, Cheech14
 
Thanks Rusty for the link, giving this a bump as it's a good read and informative for what I may do with our 67 cuda.
 
-
Back
Top