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I have the ability to acquire a 1956 324 complete engine assembly (don't have casting # yet). I want to keep my car as original as possible but would not mind if the only noticeable difference would be the #10 casting on the cylinder heads. I want to keep my original "slant pan" Hydramatic. My 1955 324 has a rod bearing and starting to knock, it also has mismatched #7 and #8 heads, so someone down the line messed with this (I thought my engine had not been apart).
I read thru the various threads and articles including the jalopyjournal.com (H.A.M.B) article on early Olds Gen 1 engines. I went thru my 1956 version Hollander manual and still have a few questions.
1. The 1956 crankshaft will not mate to a 1955 Hydramatic. I don't want to convert to the Jetaway. There is a pilot bushing in the end of the crankshaft.
Q. Can you drill a 1956 crankshaft to accept this bushing so you can run the type 'R' Hydramatic (slant pan)? The bushing P/N is 412562. I found a cross reference here: https://store.fillingstation.com/sho...&searchtype=FT
2. The intake manifolds are different. The 1955 is a 564099 and the 1956 is a 567672.
Q. Can you really use a 1955 intake manifold and just a 1956 valley pan with the hump?
Q. Is the deck height different, thus this won't work? comment - I saw post someone just hammered the relief in a 1955 valley pan.
3. The LH exhaust manifolds are different. The 1955 is 563296, the 1956 is a 567569.
Q. Nothing to worry about here, just use my old exhaust manifold? comment - assume this was just for p/s bracket or something on the 1956.
I found some disparate info on 324 engine casting numbers out there. For example, my 1955 324 is not listed in the Hollander manual even though I have a 563922 engine casting. Anyone want to comment on this list?
324 Engine Casting Numbers
567593 1956 Standard and Jetaway Trans (type 'O')
563922 1954-1955. Verified in 1955 Super 88, 100%
568922 the '8' is really a '3' ? Is this really a '57-'59 371?
566818 1954-1955 (from Hollander Manual)
568546 1956 w/o Hyd., type 'O' (from Hollander Manual) Crankshaft is 567943
568547 1956 type 'R' Hyd w/slant pan (from Hollander Manual) Crankshaft is 567443
568928 1954-1956 ?
567405 1956 ?
The Hydra-Matic was used in 1956 88s while the Jetaway was used in 1956 98s and Super 88s. So the crankshaft might already have the bushing installed. If not, you can get the crankshaft bored and the bushing installed. I've done it on a 1958 371 so that I can use the Hydra-Matic.
The main difference you will notice is the size of the valves between the '55 and '56 heads.
Wally
Yes, a few early '56s used the old slant pan before they went to the Jetaway. Didn't some of the later 88s still go to the Jetaway. It doesn't matter on that, but to your point, going to check casting numbers and end of the crankshaft, may not even have to drill it out for the bushing, but it doesn't sound like a huge deal especially if its all apart and I am doing a rebuild. My guy has 2 303s and a 324, he is in New Jersey and will send me pictures with casting numbers, etc. I will share later today. If I can pick up the '56 324 with #10 heads for a reasonable price I am going to.
Last edited by madmax442.com; January 22nd, 2024 at 08:30 AM.
There is no deck height difference, all 303's 324 are at the same height. If you are getting a complete 56 engine use the 56 turkey tray and intake with the relief already in it, otherwise put your own dent in the 55 turkey tray for some reason you need to. You may not need to machine the crank, as I believe they will be the same, check on this as it's been a long time, but I don't remember having to do any machine work on the crank on this swap...Tedd
Well I am not going with the '56 block. So we can let this thread die. I am still trying to get #10 heads, but I will rebuilding a '55 block casting # 563922.
Well I lied, not going to let this thread completely die as I did pick up a pair of #10 heads. 1 of them has 2 stuck valves, I had to pound them out, will be installing new valve guides. 1 chamber was fairly rusty, been cleaning it up, it will need decked .010 to .020 we will see.
My son called this Breaking Bad, I have the head (not in acid as they disposed of dead body parts in the series) soaking in vinegar for a day or 2. We will see, I already removed all the freeze plugs and ran a couple of cycles of rust removal and lots of wiring brushing. 4 gallons of vinegar and heavy duty tub from Walmart. Already bubbling a bunch after 4 hours. The pictures below are before this.
Valve broke off Some decent pitting Cleaning, cleaning
Well I lied, not going to let this thread completely die as I did pick up a pair of #10 heads. 1 of them has 2 stuck valves, I had to pound them out, will be installing new valve guides. 1 chamber was fairly rusty, been cleaning it up, it will need decked .010 to .020 we will see.
My son called this Breaking Bad, I have the head (not in acid as they disposed of dead body parts in the series) soaking in vinegar for a day or 2. We will see, I already removed all the freeze plugs and ran a couple of cycles of rust removal and lots of wiring brushing.
You need to "mill" both heads the same amount !
Remove .020" and see what they look like. I am guessing you might need to remove .030".
So, rinsed with water, it flash-rusted like crazy, had to neutralize it with rust removal gel spray ( could have probably used baking soda), rinsed again and its WAY better!
January 21st, 2024, 08:25 AM
