I am looking at an early 413 that has MR413 and the number 9001 stamped on the ID pad. Can someone tell me what this engine is from? Is it a car engine?

Sure that isn't an MP41?

What does the casting information on the side of the block say?

Don't have a picture of the side of the block that would show the casting number, but here is a picture of the ID pad,

The ID pad can say most anything after 50 years. Could be a rebuilder stamp or something like that. If you have a casting number from the side you can at least figure out when the block was cast. If there is a VIN stamp that might help narrow it down to. A lot of 413 engines ended up in motor homes and trucks so that is probably what it is but you won't know until you look at the casting date. I think the motor home 413 engines were cast all the way into the 70's even though they stopped using them in cars long before that.

The block should have a casting number cast on both sides of the block along with a casting date on one or both sides of the block also.
Post both of those numbers to help us help you

9004 is the build date sometime in April 1961.

That is all factory stampings. It is a 1959 passenger car 413. 9004 is not a build date it is a serial number, and they don’t match the car, but are close.

Here is the casting information on the side of the block

The books I have don't go back that far so it could be a 1961. R would be 1961 but I haven't seen the M before nor have I seen the serial number on the ID pad. But that is an early block casting so it does make sense that it is a 1961 engine.

No, not if you know these early engines, then it makes sense you don’t know what you are typing. I know you wrote a book, but not on early year 413 block stampings.

A 1961 will have R41 with the 3 missing. Then the month and day like on a 440 block.

15 years in the 300 club taught me these things.

1851629 – 1961, 413 RB-series big-block

61 and earlier 413 are easy to define,8 bolt extended shaft flange.

Can we get the casting date from the side of the block?

Wow, my memory must still be pretty good. I had a '61 413 in the late 1980s and I remembered the R41 (somebody was asking on another site a few weeks ago). Mine also had HP stamped on it (or whatever signified high perf at the time). Couldn't even get the guy 15 miles away with the 300G to come look at it and make me an offer (.030 over, no ring ridge) and he didn't have a motor for his car.

At first I was thinking the M might mean marine but more likely it's for the Marysville engine plant.

I still believe the 9004 is the build date.

What is it with some of you people? Mr Kunkel you are at the head of the line, again. You have much good info, thanks for sharing. You don’t know it all, nobody does. So stop typing out your guesses and believe that others DO know something you do not.

I wasn’t asking if you thought I was right. I wasn’t guessing. I was telling you what these numbers mean. But hey, you never believed me on other items before, so here is your proof today. Notice how the build date doesn’t appear on the stamped pad until 1960 model year.

I would have posted this info before but I had to spend some time to find it again. I didn’t really think it would be necessary and this typed info would be doubted so much. Jim Lusk thanks for posting your 1961 413 info.
More info here. http://www.chrysler300club.com/uniq/id/id.html

That data is missing some info. On non-letter series 300's, at least in 64 it was stamped V41 HP, 63 was T41 HP. My 64 300 sport series had a funky 413, originally stamped T41 HP with the T overstamped by a V. Heads had the 63 head castings with the 64 valve covers, that was the 4 bolt/6 bolt transition point. All of that was mildly interesting to me but I really wasn;t a numbers guy, first thing I did was put a set of worked 906 castings on it.

We won't even get into the max wedge 413's of that era as we are getting away from the OP's setup. Other than to say if it was stamped T41 MP you;d have a low compression max wedge and f it were stamped T41 MP HC you;d have the high compression maxie. Or whatever year letter code applied. But that is after the OP's engine was built so not applicable and to the best of my knowledge was never put in a 300, letter or otherwise.

So they made a 413 in "59? I didn't think it came out till later. When was the first 413?

Ok found it, 1959.

Max wedge info is incorrect