Re: Balance or Not
[Re: 72 RR DUDE]
#834013
10/19/10 06:55 PM
10/19/10 06:55 PM
|
Joined: Jan 2003
Posts: 9,826 las vegas
70AARcuda
master
|
master
Joined: Jan 2003
Posts: 9,826
las vegas
|
the question would be...how much has the weight of the rods ...pistons have changed?
Tony
70 AARCuda Vitamin C 71 Dart Swinger 360 10.318 @ 128.22(10-04-14 Bakersfield) 71 Demon 360 10.666 @122.41 (01-29-17 @ Las Vegas) 71 Duster 408 (10.29 @ 127.86 3/16/19 Las Vegas)
|
|
|
Re: Balance or Not
[Re: 72 RR DUDE]
#834017
10/19/10 11:13 PM
10/19/10 11:13 PM
|
Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
I just bought a cheap Harbor Freight flat gram scale for ten dollars and change and it weighs as accurate (so far ) as my buddys high dollar one. rig up a fixture in addition to your dial indicator stand & get the rod level sideways and horizontally (bore centerlines level) and weigh the small end plus seperately weigh the piston/rings/pin/locks for a reciprocating weight figure then reverse the rod/level it & weigh it w the bearing halves for rotating weight. Dont forget to zero the scale for the tare weight of the fixture you rig up. post these figures or call your machinist. this will let you if you choose to (or on a future build) polish the forging marks out of the sides of the rods and a bit of judicious grinding on the piston etc all to lighten everything then just need to hand over the crank & your math & your bill will be MUCH cheaper. The scale/fixture & 2 wheels to slip on the rod to hold the 2 rod bore sizes level all is less than the labor for a shop to weigh everything since you are now paying just for spinning/drilling the crank. I'm w Sheldon I'm a stickler for it being balanced. Yes depends on the difference between the old/new. Maybe OK (close enough) as is but I cant leave anything to chance. If you do this post your differences: (4) figures
Last edited by RapidRobert; 10/19/10 11:17 PM.
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Balance or Not
[Re: 72 RR DUDE]
#834018
10/20/10 08:23 AM
10/20/10 08:23 AM
|
Joined: Jan 2003
Posts: 75,095 A Banana Republic near you.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 75,095
A Banana Republic near you.
|
Quote:
The engine was already balanced but had very high compression pistons and I don't know what for rods. I'm going to put about 9:5 to 1 pistons in it and stock rods .I want to make it a little more then stock but not to wild since it is the original motor.
So you are putting different pistons and rods on replacing something of unknown weight and you are wondering if the high compression domed pistons weigh the same as the replacement pistons ??
Sure I 'll bite ... run it as is, having the rotating assembly balanced is just a money grab touted by greedy auto machinists ...
|
|
|
Re: Balance or Not
[Re: HYPER8oSoNic]
#834020
02/10/11 10:27 AM
02/10/11 10:27 AM
|
Joined: Jan 2003
Posts: 21,085 Niles , Ohio
therocks
oh wait.but hey.lets see.oh yeah.
|
oh wait.but hey.lets see.oh yeah.
Joined: Jan 2003
Posts: 21,085
Niles , Ohio
|
Balance it.Its not that expensive and will make the motor happy.If balancing wasnt important they would not have balanced the Hemi from the factory.I agree factory wasnt great on balancing the lower end motors.Changing to different weights will make a difference in rotating weight.Rocky
Chrysler Firepower
|
|
|
Re: Balance or Not
[Re: therocks]
#834021
02/10/11 06:47 PM
02/10/11 06:47 PM
|
Joined: Feb 2003
Posts: 12,675 Columbia, CT
moper
I Live Here
|
I Live Here
Joined: Feb 2003
Posts: 12,675
Columbia, CT
|
Yes, you MUST re-balance.
Well, art is art, isn't it? Still, on the other hand, water is water! And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now, uh... Now you tell me what you know.
|
|
|
|
|