Frankenstein 383

[RockyPat]

Hello everyone,

I took the heads off my 383 yesterday that was sitting for decades according to the previous owner.

According to the block casting, it was made in 1969.

I was expecting 906 heads...

BUT when I opened the driver side valve cover, I saw a 3751213 casting on the head. I looked it up and they came off of a 400/440 motorhome in 1973.

The passenger side head has the assumed 2843906 casting.

Both heads have 2.08 intake and 1.74 exhaust ports.

Anyone ever heard of/done this before to a motor? Is it alright to do?

Also, are the 3751213 heads any good? I should have noticed that the heads looked different from the outside. Lol

Should I try to find a singular 906 head or upgrade to aluminum - 440 source stealth heads considering the price I would have to pay to get another 906 and rebuild them both.

Thanks!

 

[RemCharger]

Had a 440 once with 2 different heads, but they were 452, 346, so very similar.
Ran fine..
But on yours yes, find a match or go aluminum..

 

[RockyPat]

Had a 440 once with 2 different heads, but they were 452, 346, so very similar.
Ran fine..
But on yours yes, find a match or go aluminum..

That is good to know about the mismatched heads.

Thanks for the advice RemCharger.

 

[4mulas]

Aluminum, unless you’re going for some oe correct resto. Especially if you’re using the 383 and the piston are low in the hole like 37 thou or thereabouts. This way you can get some 73-76cc heads and bump up the compression while you’re at it…

 

[69 Sleeper Bee]

The 213 heads were an improved version of the 346 head with improved cooling passages making them a bit more durable.
I have heard of people running different heads and never even knowing it till they were taken apart.
You can find 906 heads cheap but then factor in rebuilding cost and you may be better off going to aluminum heads which would be a major improvement ( better flow and less weight ) over anything original.

 

[BeepBeepRR]

Hello everyone,

I took the heads off my 383 yesterday that was sitting for decades according to the previous owner.

According to the block casting, it was made in 1969.

I was expecting 906 heads...

BUT when I opened the driver side valve cover, I saw a 3751213 casting on the head. I looked it up and they came off of a 400/440 motorhome in 1973.

The passenger side head has the assumed 2843906 casting.

Both heads have 2.08 intake and 1.74 exhaust ports.

Anyone ever heard of/done this before to a motor? Is it alright to do?

Also, are the 3751213 heads any good? I should have noticed that the heads looked different from the outside. Lol

Should I try to find a singular 906 head or upgrade to aluminum - 440 source stealth heads considering the price I would have to pay to get another 906 and rebuild them both.

Thanks!

Here is an idea. Take the 2 heads you have on the 440 thread and put them on the 383. Nothing was posted about those casting numbers but if you have a matching set witht he 440 slap them on the 383.

 

[RockyPat]

Aluminum, unless you’re going for some oe correct resto. Especially if you’re using the 383 and the piston are low in the hole like 37 thou or thereabouts. This way you can get some 73-76cc heads and bump up the compression while you’re at it…

At this moment in time, I am leaning towards aluminum. You make good points about the compression ratio. Thank you

 

[RockyPat]

The 213 heads were an improved version of the 346 head with improved cooling passages making them a bit more durable.
I have heard of people running different heads and never even knowing it till they were taken apart.
You can find 906 heads cheap but then factor in rebuilding cost and you may be better off going to aluminum heads which would be a major improvement ( better flow and less weight ) over anything original.

Thank you for giving me a background on the 213 heads.

I agree with your assessment of the aluminum heads and their benefits. Unless I could get a deal on an iron head and pay considerably less for a rebuild, I think aluminum is the better way.

 

[Mebsuta]

I have a 902 and a 213 on my 383 RR, and it's been that way for a long time. I pulled them off a truck with a 400 in a junk yard, which I don't think had ever been taken apart. When I needed heads decades ago, that's what I could get, so I had them rebuilt and use them to this day.

 

[PRHeads]

For a stock to mildly warmed over build, opting to get another head so you can have “matching” heads....... won’t do much of anything except make you feel better.
The motor won’t really care.

 

[RockyPat]

For a stock to mildly warmed over build, opting to get another head so you can have “matching” heads....... won’t do much of anything except make you feel better.
The motor won’t really care.

I get what you mean PRHeads. The 213 head is most likely trash anyways because it is rusted real bad. Thanks for your comment.

 

[RockyPat]

I have a 902 and a 213 on my 383 RR, and it's been that way for a long time. I pulled them off a truck with a 400 in a junk yard, which I don't think had ever been taken apart. When I needed heads decades ago, that's what I could get, so I had them rebuilt and use them to this day.

I have a feeling that the previous owners of this engine did the same thing. I am glad to hear that yours are still working great.