Does anyone know if distance between main journals 4 and 5 is the same as between journals 1 and 2?
I've got a two piece crank and a vernier and it's not quite the right equipment to make the measurements so I can complete the CAD model of it.
Thanks.
Mopar RB Crank Journal Spacing
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Re: Mopar RB Crank Journal Spacing
Rick,
I have several cranks at the shop. I will try to remember to measure a couple of them in the morning.
I have several cranks at the shop. I will try to remember to measure a couple of them in the morning.
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
www.enginerepairshop.com
Advanced Automotive Machine
Waldorf Md
www.enginerepairshop.com
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Re: Mopar RB Crank Journal Spacing
Most Race cranks are.
The OEM stuff was all over the place.
The OEM stuff was all over the place.
Helping to Deliver the Promise of Flying Cars
Re: Mopar RB Crank Journal Spacing
What is a two piece crank and why not just check the mains in the block, if the spacing is different on the crank the block will be spaced accordingly.
Re: Mopar RB Crank Journal Spacing
Thanks for the measurements, Bill, much obliged.
Diodedog, "two-piece" is another way of saying broken crank. The block, along with a new Bryant billet crank, is in Immokalee this weekend.
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Re: Mopar RB Crank Journal Spacing
What is your goal?
To make one?
Helping to Deliver the Promise of Flying Cars
Re: Mopar RB Crank Journal Spacing
My goal is to have a reasonably accurate CAD model so I can do a bunch of modals on it to understand what rpm the crank shouldn't be run. By reasonably accurate, I mean it will have the right physics but not be perfect enough to to send to CAM and make a crank. (It could be but there is minimal data I can find on the interwebs to place mains 1 and 5 perfectly and to mimic the angles of the cuts on the pork chops.)
Free-free modals are already done. Now I need to CAD up an ATI balancer and create a physically correct TC (inertia-wise) and simulate the mains and finish the analysis stuff. That will drop the torsional mode shown by a bit, I just need to know by how much as it's right at a shift point currently.
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Re: Mopar RB Crank Journal Spacing
Are you also including the attached objects?Rick! wrote: ↑Tue Nov 19, 2019 7:41 amMy goal is to have a reasonably accurate CAD model so I can do a bunch of modals on it to understand what rpm the crank shouldn't be run. By reasonably accurate, I mean it will have the right physics but not be perfect enough to to send to CAM and make a crank. (It could be but there is minimal data I can find on the interwebs to place mains 1 and 5 perfectly and to mimic the angles of the cuts on the pork chops.)
Free-free modals are already done. Now I need to CAD up an ATI balancer and create a physically correct TC (inertia-wise) and simulate the mains and finish the analysis stuff. That will drop the torsional mode shown by a bit, I just need to know by how much as it's right at a shift point currently.
Are you hoping to optimize angles of the CWs through modal analysis?
Helping to Deliver the Promise of Flying Cars
Re: Mopar RB Crank Journal Spacing
I always just go kinda high on the RPM then fix the broken parts and back off a few hundred RPM’s...LOL
NHRA SS/G
1970 AMC AMX - 390 4-speed
Advanced Clutches - Red Line Racing Cams
1970 AMC AMX - 390 4-speed
Advanced Clutches - Red Line Racing Cams