harmonic balancer

boosted68stang

New Member

Jan 25, 2009

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massachusetts

Feb 6, 2009

#1

• Feb 6, 2009

• #1

I have a 87 302 and I wanted to make sure I have a 50oz Harmonic Balancer because i have to order a new flywheel. the casting numbers are e4te-a3a on the inside it says 289 I don't know if its the original harmonic balancer or not... if it is a 50oz harmonic balancer is it worth just keeping the 50oz flywheel? or will i see more power with a 28oz set up? im new to this
thanks

 

BlownFiveLiter

have car, will race....wait, it doesn't run

15 Year Member

Nov 29, 1999

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108

Chicagoland

Feb 6, 2009

#2

• Feb 6, 2009

• #2

The balance is dependent on the rotating assembly, not the balancer and flywheel. You can't just swap from a 50oz to a 28oz without having the entire rotating assembly rebalanced. I did a quick Google search of the E4TE-A3A part number and didn't come up with any conclusive information about whether it's a 50oz balancer, or if it's 28oz. It looks to be a 50oz stock balancer, but i just don't have any solid evidence, except for what other people have stated on other forums.

 

boosted68stang

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Jan 25, 2009

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massachusetts

Feb 6, 2009

#3

• Feb 6, 2009

• #3

yeah i figured it would be more work then just changing flywheel and harmonic balancer, I just need a new flywheel and i just want the right weight, Im pretty sure the harmonic balancer is 50oz.... I think you can buy oem ones for under $50.00 maybe thats a better choice just so i don't loose sleep over it, thanks alot for taking the time to help me look

 

boosted68stang

New Member

Jan 25, 2009

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massachusetts

Feb 6, 2009

#4

• Feb 6, 2009

• #4

I took the harmonic balancer off and weighed it.. Its about 11Lbs with the masterpulley on... The flywheel I was looking at says its a 50oz flywheel but 50oz=3.1lbs

http://cgi.ebay.com/ebaymotors/SBF-...fTruckQ5fPartsQ5fAccessories#ebayphotohosting

Is this the right one? it says 24.7lbs?

I just want the right flywheel for my motor I don't want any unbalanced weight

 

BlownFiveLiter

have car, will race....wait, it doesn't run

15 Year Member

Nov 29, 1999

3,133

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108

Chicagoland

Feb 6, 2009

#5

• Feb 6, 2009

• #5

The weight of the actual item isn't what determines the imbalance. If you look at the backside of either the balancer, or flywheel you'll see a counterweight. Think of it like the weights you see on car wheels. If the wheel/tire combo were to be perfectly balanced with no weights and you were to add one, it would create an imbalance. The unbalanced weight of the balancer/flywheel counter the imbalance of the rotating assembly, so with them installed, it should equal out to zero. It's a cost effective way to manage the imbalance of the rotating assembly, as it's easier to balance an engine in this manner, than it is to weld mallory metal to the crank to achieve a true zero balance. Basically, this speeds up the process for the OEM manufacturers to assemble an engine on an assembly line.

 

L

LxVert

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Dec 26, 2003

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Feb 6, 2009

#6

• Feb 6, 2009

• #6

I want to say that if it's a factory 302 then its a 50 oz balancer and flywheel, the factory 351's use the 28 oz balancer and flywheel. I'm pretty sure thats how it is.

 

boosted68stang

New Member

Jan 25, 2009

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massachusetts

Feb 6, 2009

#7

• Feb 6, 2009

• #7

yeah your right 351 i think were 28oz and the 302 was 50oz, since the motor isnt in the car and i have to change my oil pan from 87foxbody to a 68mustang im gonna quickly check the crank#'s and look them up then order the flywheel

 

bennettracing

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Aug 26, 2002

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Ava, MO

Feb 6, 2009

#8

• Feb 6, 2009

• #8

Pre-1981 302 rotating assemblies use the 28.8oz imbalance, after 1980 they switched to the 50oz imbalance for the 302. I recently found this out the hard way. If your rotating assembly is a 1984 (E4 part number) then it uses the 50oz imbalance. Check for a stamping on the side of your factory balancer, it should give you an accurate number, don't go by just your block casting number. And remember, E=1980 4=4th year, therefore E4=1984, E5=1985, E6=1986, etc...

 

boosted68stang

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Jan 25, 2009

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massachusetts

Feb 6, 2009

#9

• Feb 6, 2009

• #9

thanks that helps out alot. its weird because the pistons are e7 (forged) and i have a e4 balancer

 

bennettracing

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Aug 26, 2002

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Ava, MO

Feb 7, 2009

#10

• Feb 7, 2009

• #10

I believe the ford part numbers on different components often times do not all match when it comes to the year. I recently had this problem when I went off the block casting number (pre-1981) when I ordered my balancer/flywheel. Luckily, I realized I needed a different imbalance. Looking at the relative part numbers will be the most effective way to go, such as looking at the part number on the harmonic balancer when determining engine imbalance.