Hey Guys- I have searched and tried to figure out this stuff without having to post a new thread but, I have not really come up with anything. So here it goes... I recently acquired an early 1949 Cadillac Motor (2 bolt valve covers) and just tore everything down in preparation for a rebuild. I also have a set of 1955 heads that I was planning on using (unless there is something I should know that will make this a bad idea). There are a few questions I had that I was hoping someone might be able to answer for me. I was not looking to do much more than stock just a mild cam, 55 heads and maybe a two 97's on top. 1. Just cleaned the oil pump today. Going to pick a rebuild kit for it however, I cant seem to find anyplace that sells the pick up tube ***embly. Is there one from another make that can be adapted or do I just clean the sludge trap I have and roll with that? 2. Since this is an early 49 It has the spring loaded cam. What does that mean for this build in terms of cam swapping? Am I stuck with what I have in regards to the stock cam? I was going to get all new lifters, pushrods, rockers, springs in addition to using the 55 heads. But I don't really know how having a "spring loaded cam" affects any of this. If I need to stick with the stocker, could I potentially have it re-ground? If so who would any of you suggest? Sorry but this is first time I have come across a spring loaded cam. 3.Are there any potential pitfalls to using the 55 heads on the 49 block? 4. Please feel free to add any other tips or tricks! I would really appreciate any guidance. Any help is totally appreciated and I look forward to your responses. Thanks a million. All the best Chris
What's wrong with your oil pick-up? I have a 49 Cad oil pickup that's been hot tanked. I can look to see if it is in good condition.
Nothing is wrong with mine, it its just really crusty. I'll take mine to the machine shop and see how it cleans up after the tank. Just thought that might be a part that was repopped.
Some stuff I found out today. Im posting this so, if down the road someone else needs this information it will be there. Called Terrell Machine in Texas and got quite a bit of information. Very nice folks over there. -To change out an early 49 cam to a later one it had been explained to me that the timing cover also has to be swapped out for a late 49 to 55? unit. The spring in the end of the cam is there for end play. The later ones use a thrust type setup. It has been also explained to me that there might be the possibility to use an even later timing cover 56-62?? (not sure if I got those years right my notes are at home) to get a better front seal. If someone can confirm of deny this, that would be appreciated. -From what I understand as well, all of 49 had different lifters and pushrods then the other years so im guessing switching to later heads and a later cam on an early 49 would also require being mindful of what lifter/pushrod combo you are using. They should match so use 49 lifters with 49 pushrods, 50-54 lifters with 50-54 pushrods. It is also my understanding that the rocker arm shaft supports are also shorter on all 49 which would would make sense why catalogs seem to group pushrods and lifters as a total 1949 item. I will try to confirm this with some measurements in a few days. All my 49 stuff is getting hot tanked at the moment. I have another set of rocker shafts that I am pretty sure are later than 49 so I will compare them with the 49 ones I have and report back. IF any of my information is INCORRECT please CORRECT me as I am relaying what my findings have been and cannot confirm any of this with absolute certainty. -In my case, I wanted to use some 55 heads I have, and it loos like in addition to changing out the cam, lifters, pushrods, and timing cover the rocker arms need to be changed as well because they changed the rocker arms in 55 so they have a different ratio. If anyone has anything to correct or add please feel free Thanks Chris
I went through all of this stuff on my 49 engine build, i used 62 heads, pontiac rods, chevy lifters, Mondello adjustable pushrods, 390 exhaust manifolds, delta cam. bored 30 over, balanced. I thought I was really on top of it, it ran good. I wished I had it to do over, I would use all the stock parts, with the exception of maybe a higher compression piston, and the 58 eldorado cam is a pretty good street grind. I have a 51 engine and it runs so smooth and quiet, the only noise is the fan. these are awesome engines
Thank you for your response. Was your 49 an early or late? Ive been trying to do all my homework but, the oddball early 49 motor keeps throwing me for loops. I do have the 49 heads with the nice 2 bolt valve covers that I could still use provided they are not cracked. I plan on taking them to get magged and cleaned soon as I can just so I know. I have heard good things about the 55 heads and I have a set so, I thought why not? But, it has gotten pretty deep pretty fast but, I feel like I may be finally starting to get a grip on what all is involved with this swap. But, I still will take all the feedback I can get. Thanks again
If you use the '55 heads just use the 55 rockers and shafts. You'll probably want 55 pushrods, they're shorter than the 54's. They went to a rubber front seal in '56 so you'll want one of those. The old felt seal is a PITA to install but seems work well, at least on my engine.
I also found that all the old guru's from the allard days are gone. My engine came with the 55 heads, and a 2x4 intake. The first series engine is rare and for sure a novalty, why not use it all? I have some valve covers and intakes for the 2nd generation 49's, I also have a belhousing and a trans and drive shaft for a 51 oh and a complete 51 engine if you need any parts.
Thank you so much to those who have taken the time to reply. It has helped a lot. @warbird1 So the 56-62?? Timing cover will work on the 331 without any issues? I was unsure if that was the case. But, if it does that is good information to have and I will get one of those for sure. @ancientiron thank you for your input it is very appreciated. I might still use the 49 heads I will have to have them inspected and cleaned. Very strong possibility I might go that route and ask 73RR to grind the cam for me, and throw a 2x2 or something on top. Or if I get a later cam and later timing cover use that on the 49 and byp*** that spring loaded cam deal. That should work correct? As long as all the other valve train components match? Im definitely replacing lifters and pushrods and maybe rocker arms as well. Which leads me to my next question, can anyone suggest good lifters from anywhere? I called Schneider a few days ago and they said the have them and I believe they are USA made but, I don't know where they are sourcing them from. If I do end up using the 55 heads one thing I am missing for them is the rocker shafts. I know they changed the rocker arms for 55, the shafts from what I understand are the same but, are the rocker shaft mounts taller or are all the rocker shaft mounts the same on all years? Im just trying to make sure im not overlooking something. If I had another shortblock, I would certainly build the 49 with the heads that came with it and use the 55 heads on a different motor.
As far as I know the 56 and later front covers will work on the earlier engines, though I don't know if they'll work with the spring loaded cam.
I run 49-62 Cadillac engines. My experience has been that if a head cracks, it's always been on #5 cylinder. I don't know if it's true, but I've been told that the early 49 has floated wrist pins. If you need parts, I might be able to help.
@cadlasalle The early 49 does indeed have floating wrist pins. Separated a rod and piston last night. Called egge yesterday and was trying to confirm that their pistons would work and they could not confirm if their CAD pistons had provisions for the retaining clips. Looks as though I will be purchasing my Pistons from Terrell machine as they definitely are set up for that. They told me that for some odd reason even their later pistons 53-55 (I believe it is) have been machined to accept floating wrist pins. If I run those 55 heads don't know if I should get the later pistons, I was told that one of Terrell machines customers had purchased those to run in an earlier block and it worked with no issues. Anyone tried this?
I ordered pistons from egge and they came with bushings for the pins. i have my old pistons and rods if you need them.
Be careful , measure rocker shaft length and match to rockers, re***emble to match the original ***embly.. you can get my 51 short block cheap.. thanks ancientiron
Looks like I definitely should pick up a full set of 55 rocker shaft ***emblies. If any one has a set in good shape please let me know. Want to make sure they are 55's though just to be on the safe side.
The Jalopy Journal
