1971 ( 340 ) Block & Crank obtained !

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SS Lancer

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Ok well finally obtained my back up block or a spare this is a 71 model 340 its pretty rough now but after its baked and blasted it should look 100 % better got a feeling this one is going to need a 40 or 60 over on bore !
Does anyone have some 60 over Dome 340 pistons that need a good home ?
Thanks Chris

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Crankshaft appears cast, which would indicate that it is not a 71 crankshaft. Better pictures would help.
 
The lifter bores may need work. If they rust a lot and then get honed out to clean them up, then they may be so big as to become big oil leaks in the main oil distribution system. That'll lead to big issues for the crank oiling, etc. So you might need to be prepared to do some of the fixes for that, like tubing the galleries.
 
The lifter bores may need work. If they rust a lot and then get honed out to clean them up, then they may be so big as to become big oil leaks in the main oil distribution system. That'll lead to big issues for the crank oiling, etc. So you might need to be prepared to do some of the fixes for that, like tubing the galleries.
Thank you for the info either way it want see the elements anymore maybe they will clean up relatively easy , this is my back up block for the future . If I had to I guess I could have the lifter bores bushed it no other option.
 
Ten four - blocks at machine shop currently .

Dont remember
Day & month but it had 1971 or 71 on it.
I have a good another one currently and its a 69 model Im going to use it which is 4.080 bore unless I find some 60 over Dome 340 pistons then will use the 71 model which was the one in rusty condition.
 
Dont remember
Day & month but it had 1971 or 71 on it.
I have a good another one currently and its a 69 model Im going to use it which is 4.080 bore unless I find some 60 over Dome 340 pistons then will use the 71 model which was the one in rusty condition.

Before and cleaning of the 69 model doing some deburring then its back to machine shop .

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Parting line is wide and it has the distinct ring when tapped with a hammer ( Crank ) that is .

Ok cool. I was going by the very distinct sharp edges of the counterweights. That usually points to a casting. Either it's been dressed, or the picture just doesn't show details.

Oh and the hammer taping thing doesn't always tell the truth. I have a nodular iron Cleveland crank and it rings louder and cleared than any forged crank I've ever heard. So watch that one! lol
 
Ok cool. I was going by the very distinct sharp edges of the counterweights. That usually points to a casting. Either it's been dressed, or the picture just doesn't show details.

Oh and the hammer taping thing doesn't always tell the truth. I have a nodular iron Cleveland crank and it rings louder and cleared than any forged crank I've ever heard. So watch that one! lol
Ten 4 - thank you Hoss
I will send better photos after she is more presentable this is my 69 340 its cleaned now patiently waiting.

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Ten 4 - thank you Hoss
I will send better photos after she is more presentable this is my 69 340 its cleaned now patiently waiting.

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This one was weird atleast to me it had dated bearings on mains and rods but has a 20 over bore ?
I have read before where manufacturers sent new blocks out that weren't standard bore I guess Chrysler did also.
 
This one was weird atleast to me it had dated bearings on mains and rods but has a 20 over bore ?
I have read before where manufacturers sent new blocks out that weren't standard bore I guess Chrysler did also.

Yup they sure did. Also, someone could have reused the bearings. The world wasn't as replace happy a long time ago as it is now.
 
Thank you for the info either way it want see the elements anymore maybe they will clean up relatively easy , this is my back up block for the future . If I had to I guess I could have the lifter bores bushed it no other option.
Yes, you can, but the cost is usually quite high. It tend to shy away from rusty blocks for that reason. Ask your shop how they can clean the lifter bores up. They need to be darned clean; any rust particles left in the surface can work out and treat your lifters like a termite loves wood.. iron oxide is an abrasive! One they are darned cleaned and honed, then the bores can be measured to see how loose they will be.

Perhaps others can suggest how loose the lifter-to-bore clearance can get without dropping the main distribution pressure too much. I don't know a good clearance numbers on that, besides the factory numbers. The passenger side lifter gallery doubles as the MAIN distribution feed to everywhere in the engine, so that is why it is critical, especially since you are going to be turning very high RPM's all the time.
 
I have used brake cylinder dingleberry hones with really good success on lifter bores.
 
I have used brake cylinder dingleberry hones with really good success on lifter bores.
Brake cylinder dingleberry, I have not seen one of them before.
The brake hones that I have seen are the three stone style.
 
Brake cylinder dingleberry, I have not seen one of them before.
The brake hones that I have seen are the three stone style.

Just search EBay. I like the 320 or 400 grit. They just do a cleanup with minimal metal removal. Search "ball hone" for a 1" diameter. That's what I use.
 
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