Rotating Assembly

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Ron_Hall
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Rotating Assembly

Post by Ron_Hall »

After the assembly was installed in the block I found out the pistons were for a truck motor so I changed them to car pistons.
Question is: The new pistons are 10 garms more so do I need to re-balance the assembly?

Thanks
Ron
1971 F100 SWB 390 FE - bored.030 over
Edelbrock Performer - Holley 600 CFI
Stock heads with some porting - Sanderson FF427 Headers
C6 with stock converter - 3.25 rear end gears
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Manny
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Re: Rotating Assembly

Post by Manny »

Sorry nobody jumped on this but i will throw my :2cents: in. Changing the pistons should be no issues. the fact that they are 10 grams heavier than the old is not an issue. For a good balanced assembly set them all to the same weight. pick your lightest one and set to that one is standard balancing. Having them balanced like your talking is way better than ford would have pulled off. Ford i am 90% certain never ran them across a scale.... :thup:
Just another Ford fool named Dan.
The Junk that hangs around
67' F-250 highboy Camper special cross breed currently under way
http://www.fordification.com/forum/view ... 22&t=86706
1974 Bronco 302 3 speed
1984 bronco 302 c6 35's
1994 F350 7.3 5spd dually.
woods wrote: The rust holes in my truck were a factory install (very rare).
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Ron_Hall
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Re: Rotating Assembly

Post by Ron_Hall »

Thanks Manny!
The new pistons are Keith Blacks and all though they are 10 grams heaver they are all with in 1 gram. 7 are .884 and 1 is .883. My local speed shop would do it for $125 I just didn't know if it was a waste of money or not.

Thanks again
Ron
1971 F100 SWB 390 FE - bored.030 over
Edelbrock Performer - Holley 600 CFI
Stock heads with some porting - Sanderson FF427 Headers
C6 with stock converter - 3.25 rear end gears
One owner...
User avatar
Manny
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Location: Georgia, Lake City
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Re: Rotating Assembly

Post by Manny »

That's a waste of 125 to me. If i am within a gram here at the house i cal that more that good. Certain that 302's at the factory were lucky to be withing 30 of each other. :thup:
Just another Ford fool named Dan.
The Junk that hangs around
67' F-250 highboy Camper special cross breed currently under way
http://www.fordification.com/forum/view ... 22&t=86706
1974 Bronco 302 3 speed
1984 bronco 302 c6 35's
1994 F350 7.3 5spd dually.
woods wrote: The rust holes in my truck were a factory install (very rare).
User avatar
Ron_Hall
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Posts: 214
Joined: Sat Oct 22, 2016 2:59 am
Location: Reno, NV

Re: Rotating Assembly

Post by Ron_Hall »

Manny wrote:That's a waste of 125 to me. If i am within a gram here at the house i cal that more that good. Certain that 302's at the factory were lucky to be withing 30 of each other. :thup:
Thanks Manny... That's the way I was feeling but wanted some opinions from the guys here.
Thaks again

Ron
1971 F100 SWB 390 FE - bored.030 over
Edelbrock Performer - Holley 600 CFI
Stock heads with some porting - Sanderson FF427 Headers
C6 with stock converter - 3.25 rear end gears
One owner...
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