Raydermiike

I just bought a 1967 Cutlass, I was told it had a 455 from a 1969 Toronado. The casting on the heads is C 394648 and the engine casting above the water pump is 389244D which comes up as a earlier 425 how can I confirm what I have here. Thanks for your help.

2blu442

Well, the D block is a 425 block. But if its been rebuilt one can put the guts from a 455 into a D block and have a 455. But lets back up a little. The C heads on a 425 should have a letter and number code stamped into the end of one head. If the heads have not been swapped it would be on the front of the passengerside head. Something like this:

PC221862_zpscf45a207.jpg


A few more clues to look for, the harmonic balancer behind the crank pully would be one diameter and thick, like the one below:

P1010066.jpg

The 425 is thinner and has more of a step on the backside. I believe they all had two small C shaped notches across from each other. Like on this engine if you can see it:

P1010199.jpg

There's a few other things that can be hints, such as the numbers on the carb, distributor, and intake. Those may or may not clarify what you have depending on if it's been apart. Many of these items will interchange with other engines.

MDchanic

You can look for an engine number here:
,
which will tell you the year if the engine is '68 or later.

If no stamping on the pad, the vertical surface of the front of the right head should have a number for pre-'68 cars (could be on the back of the left head, too).

If earlier heads were installed on a later engine, of course, it could have both numbers.

If you post a photo, that would be the most helpful.

- Eric

edit: Beat me to it, John!

edzolz

This sums it up. The only way to tell for sure is to tear it down.

Raydermiike

The number stamped on the passenger side head is R059477T The harmonic balancer doesn't look quite that thick. In any case whatever it is it can't be out of a 1969 Toronado at least originally.

MDchanic

R______T is the correct code for a 10.5:1 1967 Toronado 425, so, at the very least you've got one Toronado head.

At the most, you've got the whole motor.

If you've got the whole motor, and it's in good shape, it's pretty much the best Olds motor you could have, short of the hot-rod W-motors.

- Eric

2blu442

As Ed said there's no way to know for sure without taking it apart. But if it doesn't look like its been apart there are some clues that may lead you to what it likely is. Eric keyed out your head for the Toronado application. The Toronado intake manifold was sunken in the center. It also has the choke in a little box that's bolted to the intake. Here's a couple pictures of a 1967 Toro intake (rusty colored) and a mid-1970's 455 from some other model. Note the height of the location where the carb attaches.

P2180152.jpg

P2180151.jpg


If the carb number, and distributor number are correct for the 1967 Toronado, and it looks like it's never been apart... then it might be a reasonable guess that its a complete Toro engine. John

Raydermiike

You all are very helpful, thank you. Is there a way to confirm the other head short of tearing the engine apart since I am no mechanic. If I can go out on a limb, I have a 66-67 425 block a 425 head, assuming this is the whole 425 possibly made into a 455 is it a desirable engine and would it have been better to keep it a 425 if changed. Thanks ahead of time for any info I can get. It has an HEI distributor and an Edelbrock carb so those are of no help.

MDchanic

They only marked one head, so there is no way to tell from the other head whether it's original.

Sounds to me like it's an original engine, so long as it has no signs of prior disassembly (sometimes you can't be sure). You could always look into the spark plug holes with a bore scope to see if the pistons are original.

As far as the displacement, non-Olds people aren't usually aware of the displacement increase in 1968, and will call all big blocks 455s.

Most agree that the 425 is a better motor, unless you're using every cubic inch drag racing.

- Eric

Raydermiike

The 67 manifold looks like the one on the car. At this point it is at least looking very much like a 67 425 and it may have been converted to 455 which I guess will not be known unless it is taken apart. Is that an engine you would keep if you ever sold the car or is it not that big a deal. You guys rock. I have owned cutlasses 442's even a hurst olds since I was a kid but as you can tell I am not real savy when it comes to the numbers or mechanics of things.

2blu442

If its running OK I'd just drive it! The higher compression engine may need higher octane gas to keep from pinging. If it is a 425 then I believe it was 10.25:1 so you may want to listen for that.

John

svnt442

You would also have a steel crank if it's a 425 with a different bolt pattern than a 455 would have. If you don't want to pull it apart just for the sake of pulling it apart, then all you would need (if you are pulling the engine) is a known 68-90 flex plate or flywheel to compare to the crank. This would be definitive in my book.
Lol....If the flex plate don't fit...you must acquit.

MDchanic

If you have a later flexplate, then the crank has been replaced.

If you have an earlier flexplate, then it has not.

- Eric

Raydermiike

So does that mean the 425 crank would have to be replaced if it is now a 455? I understand the 425 crank was desirable feature.

MDchanic

Yes, it does, as I said in response to your now-vanished question.

- Eric

Octania

Since you have a D-425 block, the next thing you need to know is, is it the TORONADO type block. This matters on many levels. Look for this drill spot. FAR easier than finding a VIN stamp anyhow.

http://i19.photobucket.com/albums/b1...-425_CN6-1.jpg

4040_66-To-425_CN6-1.jpg

While true that it could still be a 455 in that block, also true that none of the above are bad things, just varying degrees of good, with the 66-67 Toronado with the Drill Spot on that rib next to the oil fill tube being the best of the best. Which evidently you have, pending outcome of the drill spot search.

Pre-68 engines have a slide-on oil fill cap; 68+ are twist-on. Not definitive, but good supporting evidence.

One need not test fit a flexplate to ID the crank, just remove trans inspection cover and peek at the notch on the OD of the crank flange. Forged cranks such as your 425 have an L shaped notch; 1968+ cast cranks have a C shaped notch with the exception of the hella rare 68+ forged crank which has a J shaped notch. So easy.

Congrats on your 455 actually being a Toro 425.

Raydermiike

Sorry, I meant to reply to a response so I changed it. You were too quick, lol I really appreciate it though. One more I'm sure dumb question, if it has been changed I imagine a 425 crank is impossible to find which would just make the desirable 425 now just another 455.

MDchanic

You can find 'em.

Several members here have extras lying around.
I've got one, but I'm keeping it for when I build that motor.

From what I've seen, though, you don't need one because you've already got one.

- Eric

Raydermiike

P1010108.jpg
Is this the drill spot?

MDchanic

Yup. That's it.

Congratulations.

Now you've got to paint it blue.

- Eric

Octania

Looks exactly like a Drill Spot

MDchanic

I hate to say this, Chris, but his Drill Spot picture is a lot better than yours.

- Eric

Raydermiike

Thanks to all of you for your info. If anyone can tell me where or how I can find out more about this block/engine I would be grateful.

75cutty455

Go here
Engine

http://www.442.com/oldsfaq/ofeng.htm#Engines

Block

http://www.442.com/oldsfaq/ofblk.htm

Heads

http://www.442.com/oldsfaq/ofhed.htm#Heads

Octania

I noticed that
How kind of you to point that out....
Considering the Potato I used to take that photo, it has worked out OK
Maybe he'll be nice enough to let us use that photo for future show & tells.

Octania

I noticed that
How kind of you to point that out....
Maybe he'll be nice enough to let us use that photo for future show & tells.

Raydermiike

My photo is your photo.

MDchanic

Potato?

- Eric