Mopar R3 Block

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Dmopower

Dmopower

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Hello Guys and Gals. I have the opportunity to purchase a new never ground on R3 engine block tomorrow. I'm low on time to do adequate research on my own. I am looking for a HD block to build a large street engine out of for my 67 Cuda. I do NOT know what to look for and would appreciate any input and insight as to what the differences are. It is said to be a std bore and std lifter angle. Are all 59 degree blocks 9.6"? Is that what I want for a street engine running victor heads? If I buy this I will be selling my 70 std bore 340 block. Thanks in advance for the help folks.
 
9.60 and 59 Degree are the simple and easy way to go.
Measure before purchase as NOT all 59 degree are 9.60
several of mine ARE 9.20!
 
GTX JOHN said:
9.60 and 59 Degree are the simple and easy way to go.
Measure before purchase as NOT all 59 degree are 9.60
several of mine ARE 9.20!
Click to expand...

Thank you. A couple questions. The cam bearing holes are huge. How do I address this? and how exactly do I measure the deck height accurately? Is there a part number to look for? If I buy a 48 degree what is involved in making it a street engine? Thanks again John.
 
Avoid the 48° blocks, they require special cam cores, probably not available, also some had roller cam tunnels. A picture of the lifter valley will help identify. Also the 9.0 deck and 9.2 deck blocks limit the stroke capability, they were intended for 358" big bore short stroke combinations.
 
Also keep in mind, the short deck versions require a special timing cover and intake manifold
 
A tape measure from C/L of Crank location to top of deck should be adequate
to tell .400 or .600 differences in blocks = about 1/2 inch
 
replicaracer43 said:
What you REALLY want is a 59° std deck 4 bolt main, with 340 main bore tunnel.
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I'll see it and take pics tomorrow. What I have been told is. It's new never been built, it has std lifter bore angle it has a std 340 bore and the cam bearing holes are not std 340. I can get this pretty cheap. Thats why I may be interested in a 48 degree block as well. I'm just not sure what all needs changed
 
The timing cover and camshaft will cost you plenty for this combo.
I would sell it and use the money on the standard block.
 
Dmopower said:
I'll see it and take pics tomorrow. What I have been told is. It's new never been built, it has std lifter bore angle it has a std 340 bore and the cam bearing holes are not std 340. I can get this pretty cheap. Thats why I may be interested in a 48 degree block as well. I'm just not sure what all needs changed
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I believe there were some improperly machined 59° blocks floating around, you must be VERY careful about that, they had the wrong tunnel. I cant remember exactly, but it may have had the large tunnel for 48° cams, but with 59° lifter bores.
 
The big if. I plan to avoid the 9 and 9.2 blocks as I plan to stroke this. If this is a 9.6 48degree block. what would need to be done to run this on the street with victor heads? What do people do for the cam bearing hole size. Sorry guys I'm very new to the SB mopar and am short on time to learn.
 
You cant use a 48° cam in a 59° block, even if it fits the tunnel, the timing specs are off. And mopar use to sell the 48° cores as unground, but I think they have been obsolete for some time. My advice is to build a conventional LA or magnum based engine, or move right to the gen3 hemi platform
 
replicaracer43 said:
You cant use a 48° cam in a 59° block, even if it fits the tunnel, the timing specs are off. And mopar use to sell the 48° cores as unground, but I think they have been obsolete for some time. My advice is to build a conventional LA or magnum based engine, or move right to the gen3 hemi platform
Click to expand...

ok. so if it's the 59 degree 9.6 deck block that I want. What does a guy do for cam bearing or does a guy have a cam made for the bigger holes?
 
Dmopower said:
ok. so if it's the 59 degree 9.6 deck block that I want. What does a guy do for cam bearing or does a guy have a cam made for the bigger holes?
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If it has the wrong cam tunnel, I dont know, that's probably what makes it "cheap" we have a FABO member @Rocket that knows more than I do about the difference, hopefully he will chime in
 
The large cam tunnel was for needle roller bearing (torrington) type bearings.
AD15DC48-EC03-489E-9140-48E10F82B005.png

@Rat Bastid knows his way around the different R3 blocks I believe.
 
Can these blocks be run with flat hyd lifters?
 
I also recently had the opportunity to purchase a new R3 with a new crank. He also had one of the later Mopar racing heads and I saw another head on ebay. I was really wanting a small block Mopar that could turn some serious rpm. After reading about all the special parts required, and how hard they are to find, I think I came to my better senses.
 
is there something written, stamped on the block that says 48 degree or 59?
 
tinman2 said:
I also recently had the opportunity to purchase a new R3 with a new crank. He also had one of the later Mopar racing heads and I saw another head on ebay. I was really wanting a small block Mopar that could turn some serious rpm. After reading about all the special parts required, and how hard they are to find, I think I came to my better senses.
Click to expand...

I don't want to do a bunch of special work either. But I don't even know what the options are yet. If it's a 9.6 block with 59 lifter bores all I have to deal with is the cam bearings I think. Don't these blocks use both std head bolt pattern and the w5 stuff?
 
Dmopower said:
I don't want to do a bunch of special work either. But I don't even know what the options are yet. If it's a 9.6 block with 59 lifter bores all I have to deal with is the cam bearings I think. Don't these blocks use both std head bolt pattern and the w5 stuff?
Click to expand...


You should be able to spot the 59/48 LBA a mile away. The one doesn’t look anything like the other.

Not sure why you are worried about cam bearings. I don’t want to go back through the thread to see. But unless the block was machined for bigger than OE cam bearings it is what it is.

All the blocks have the same 10 bolt pattern, but some of the blocks have another 10 bolt holes in them. Any 10 bolt head will bolt on any block. Any 20 bolt head will bolt on any block, you just won’t use the upper and lower rows of bolts.
 
Rat Bastid said:
You should be able to spot the 59/48 LBA a mile away. The one doesn’t look anything like the other.

Not sure why you are worried about cam bearings. I don’t want to go back through the thread to see. But unless the block was machined for bigger than OE cam bearings it is what it is.

All the blocks have the same 10 bolt pattern, but some of the blocks have another 10 bolt holes in them. Any 10 bolt head will bolt on any block. Any 20 bolt head will bolt on any block, you just won’t use the upper and lower rows of bolts.
Click to expand...

Thank you. I get that the valleys don't look alike. But can you show me which is which?

I'm surfing the net for the info but it's spotty. I only mentioned the cam bearing holes because the machine shop owner where it's at mentioned it had larger than stock cam bearing holes and the roller ones I was shown said racing only. I'm going to drive this all the time. will the roller bearings hold up to that kind of use?
 
Outta my experience range, but sounds kinda like a little bit of a Pita, with another of grey, and expensive areas
 
Ironracer said:
Outta my experience range, but sounds kinda like a little bit of a Pita, with another of grey, and expensive areas
Click to expand...

I won't know if it's a pita until I get the intel I need to make that call. If it's a 59 block, 9.6 tall and the cam bearings isnt an issue. I don't see an issue at all. But that's why I'm asking the questions. A pic defining each valley would go a long way for me at this point.
 
These are the best two pictures I pictures I could find real quick. The 48 degree block picture I pilfered from here on FABO. The other came from FBBO.

Here is the 48* LBA
1819921A-0987-406F-A0A1-2B8B4C43F966.jpeg


Here is the 59* LBA
405C0DA3-5C6F-492F-8570-EF8A9D3E1EDA.jpeg


As you can see, the 59* LBA is laid towards the cylinder walls and the 48* LBA is stood up and moved towards the cam.
 
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