318 Connecting Rods and Crankshaft

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Not arguing the fact that it definitely needs to be balanced, the one we did internal balance only required weight taken off. No heavy metal was added.
 
Well,as sometimes happens, this entire discussion may be mute. I am going to visit a fellow FABO member later this week that happens to have a cast crank, a steel crank, with rods etc from a couple 318's he is parting out. If the parts measure out properly, I will probably purchase the lot from him. This would allow me to accomplish what I started out to build; just a nice strong, reliable 318. If this does not work out, I'm back to a stroker. However, nothing ventured, nothing gained.
I'll let all of you know what happens. Who knows, maybe I will build a second motor.
 
Nothing wrong with the keeping it simple. Hope it works out for you!
 
Man can't have enough good usable parts or engines around, hopefully it will be a nice score!
 
Man can't have enough good usable parts or engines around, hopefully it will be a nice score!

I'm not going to say that I'm a parts hoarder, nor am I going to say that it was easy to throw out that old 318 block with the broken ear. But... it's a bit difficult to get in the shed and move about. Same goes for my bedroom closet. Hey! I don't want some of that stuff even getting surface rust!
 
My stroker pistons were 547g (with rings) and 699g with pin. I got that Eagle forged crank standing in the garage, you need some dimensions of the counterweights? thickness will be very similar but the shape will dictate the mass of the bobweight. With the SCAT crank having a 17xxg bobweight target, your going to have to add expensive tungsten if your not running lightweight stuff. Lighter rods come to mind. Also the 4" crank with cap style rod bolts (no nuts) will clear the rails, the bolt style wont. Just a dime sized crescent cut with a die grinder will clear them.
 
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My stroker pistons were 547g (with rings) and 699g with pin. I got that Eagle forged crank standing in the garage, you need some dimensions of the counterweights? thickness will be very similar but the shape will dictate the mass of the bobweight.
Odd..... with that piston weight and pin weight (152 grams from your numbers above), I come up with 2121 grams bobweight with the stock heavy 318/360 rods. Something is 'not computing'....The numbers I am using for that computation:
  • Piston 547 grams
  • Pin 152 grams (based on your total of 699 grams)
  • Rings 52 grams
  • Rod bearing 44 grams
  • Pin lock 0 grams
  • Rod small end 240 grams
  • Rod big end 518 grams
  • Oil on journal 4 grams
I'd love to see some pix of the Eagle crank clearly showing the counterweights. Yes, part of the target bobweight is in the counterweight shape, but the angles of the counterweights on the crank figures into it too. I'll work on getting some pix of the SCAT cast crank to post for comparison.

BTW, that 1760 gram maximum bobweight for the SCAT cast crank for internal balance has been posted by someone here who has balanced up some of those cranks and found the number on their own. I indirectly confirmed this with a call to SCAT; they stated that they need to add a small amount of weight to these cranks with their approx 1800 gr bobweight sets to achieve internal balance.

Tnx; just trying to learn what is what.
 
IIRC.... the Eagle cast crank have reportedly had some breakage issues in the past that the SCAT's have not had..... but who knows how the parts may have been abused. The OP is not pushing this engine so I'll bet you will be OK either way.

70aarcuda has used a number of SCAT cranks IIRC.
I have three guys who do machine work for me... none will recommend Eagle cranks or rods.

I'm no expert on balancing but many shops love the guys who are scared to death of not making everything exactly perfect. These guys have told me get all the rods and pistons close, send the crank to get balanced and run it.

You can get 150,000 miles or more out of a factory balance job. And those were rarely balanced closer than 20 or 30 grams.
 
Odd..... with that piston weight and pin weight (152 grams from your numbers above), I come up with 2121 grams bobweight with the stock heavy 318/360 rods. Something is 'not computing'....The numbers I am using for that computation:
  • Piston 547 grams
  • Pin 152 grams (based on your total of 699 grams)
  • Rings 52 grams
  • Rod bearing 44 grams
  • Pin lock 0 grams
  • Rod small end 240 grams
  • Rod big end 518 grams
  • Oil on journal 4 grams
I'd love to see some pix of the Eagle crank clearly showing the counterweights. Yes, part of the target bobweight is in the counterweight shape, but the angles of the counterweights on the crank figures into it too. I'll work on getting some pix of the SCAT cast crank to post for comparison.

BTW, that 1760 gram maximum bobweight for the SCAT cast crank for internal balance has been posted by someone here who has balanced up some of those cranks and found the number on their own. I indirectly confirmed this with a call to SCAT; they stated that they need to add a small amount of weight to these cranks with their approx 1800 gr bobweight sets to achieve internal balance.

Tnx; just trying to learn what is what.

Cool, Ill try and get some crank pics and big and little end weights of my rods for your calculations. My big/little rod fixture was still a little wonky but I bet we can get it to +- 5g. If I can get to within 20-30g of the 2050g bobweight, Id be set to put this thing back together. No locks, these are press fit.
 
As Promised.
Visited a fellow FABO member to day and came home with a steel crank, set of floaty pistons and rods (pistons are standard so they won't work with my +.030 bore but we didn't feel like separating them), a set of '67 closed chamber heads and all the valves were in very good condition, some pushrods, and a few minor bits and pieces.
Being old and forgetful, I forgot to bring a mike to check the crank, so no measurements. But we did check all the bearings and the crank and found no indication the crank had been turned sometime in the past. I suppose it is possible the motor was never opened since it had standard pistons. Maybe it has but we didn't find any markings, etc. Measurements will tell the tale. At the very least the crank will need polished.
the heads are casting number 2658920, which shows up as a 1967 273 or 318 with 1.78 intakes and 1.50 exhaust with 62-65.5 cc. I'll have to cc them to find where they fall in that range.
As an aside, the block showed a November or December (can't remember which) 1966 date. I didn't write the casting number down, so I can't pass that on.
So, I'm back to where I really wanted to be: just a nice stock stroke, strong, reliable 318 with some balls.

Thanks everyone for the comments, advice, and help.
 
Congratulations, Nice score on those heads, I’d like to get some of those myself! The steel crank ain’t bad either. Some say Chrysler started hardening the valve seats sometime in ‘67, but I haven’t confirmed this myself.
 
I do not think that early on the seats and after a couple of valve jobs or larger valves it's gone anyways
nice find
 
I didn't think to ask permission to mention his name, so I won't. He is a super nice guy. We just went through his stash of parts he had no need of and wanted to clear out and put some coin in his pocket. When we had piled what I needed, wanted, lusted for, we set down in his shop with a cold bottle of water (too dang hot for beer and I had a 2 hour drive home) and agreed on a price. Like almost all of us he is a "low buck" kind of guy. Price was not cheap and not high, but very fair. He was happy and I was happy. The best kind of deal.
So, I got to meet a nice guy that opened his home and his shop to me, his nice wife, shoot the breeze, learned some MOPAR stuff from each other and have a good time looking for MOPAR treasures. All because of FABO. Does it get any better?
 
Congratulations, Nice score on those heads, I’d like to get some of those myself! The steel crank ain’t bad either. Some say Chrysler started hardening the valve seats sometime in ‘67, but I haven’t confirmed this myself.
I have no knowledge about the seats in 67, but I think that is a bit early for that. As I recall, hardened seats started happening when the lead was removed from the gasoline. But as usual, I am probably wrong.
 
Some people in the know say that Chrysler knew about the change to unleaded several years ahead of time and began hardening the seats, but that seems awfully early to me, too. I would think more starting around ‘70-‘71 myself.
 
As Promised.
Visited a fellow FABO member to day and came home with a steel crank, set of floaty pistons and rods (pistons are standard so they won't work with my +.030 bore but we didn't feel like separating them), a set of '67 closed chamber heads and all the valves were in very good condition, some pushrods, and a few minor bits and pieces.
Being old and forgetful, I forgot to bring a mike to check the crank, so no measurements. But we did check all the bearings and the crank and found no indication the crank had been turned sometime in the past. I suppose it is possible the motor was never opened since it had standard pistons. Maybe it has but we didn't find any markings, etc. Measurements will tell the tale. At the very least the crank will need polished.
the heads are casting number 2658920, which shows up as a 1967 273 or 318 with 1.78 intakes and 1.50 exhaust with 62-65.5 cc. I'll have to cc them to find where they fall in that range.
As an aside, the block showed a November or December (can't remember which) 1966 date. I didn't write the casting number down, so I can't pass that on.
So, I'm back to where I really wanted to be: just a nice stock stroke, strong, reliable 318 with some balls.

Thanks everyone for the comments, advice, and help.

Here are the block #s
20190502_185616.jpg
20190502_185643.jpg
 
Looks to be an early 67 model? Or is it a poly?
 
I'm not going to say that I'm a parts hoarder, nor am I going to say that it was easy to throw out that old 318 block with the broken ear. But... it's a bit difficult to get in the shed and move about. Same goes for my bedroom closet. Hey! I don't want some of that stuff even getting surface rust!
I have a stroker crank in my living room.
 
report on the cc
they are a going to be larger stock
also put on a block and scribe around the bores if you plan on unshrouding the valves
 
report on the cc
they are a going to be larger stock
also put on a block and scribe around the bores if you plan on unshrouding the valves
Report on the CC! Yes sir, got right on that. Here ya go:

"they are a going to be larger stock": Not sure if this is a statement or a question that the chambers would be on the high side at 64-65cc. What did you mean?

Now keep in mind I am 70 years old and my eyes are not what they used to be and the markings on my burret are a bit hard to read. I only measured one head so far and they measure 62, 62.8, 62, 62cc. The 62.8 chamber I am positive is a measuring and operator error. The valves appear to have been done sometime not too long ago so at least a surfacing on the head face was likely done. I have no way to determine if the head was milled. I removed one exhaust valve for inspection. Cannot remove any more cause my ancient valve spring compressor finally gave up and died. It was my grandfather's. I'll give it a suitable "burial" by hanging it on the wall in a place of honor. Motor appears to have run very rich or maybe using some oil based on the amount of carbon buildup on the valve stems on the chamber side. Did the finger suction test and valve stem wiggle test for valve guide clearance and that specific guide seems just fine. Valve stem seals are umbrella style and not brittle, but maybe not sealing as well as they should. Makes no difference, I am doing a valve job anyway so at least I will know where I started.
I have a set of KB167 +0.030 pistons on the way. That will put compression about 9.5 or so, which is where I wanted to be.
I have no plans to enshroud the valves. For my use, the heads will be just fine as they are.
 
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