302 C4 swap for C6: Flywheel counterweight
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302 C4 swap for C6: Flywheel counterweight
Lads,
We are replacing a dead 302 with a kid's killer Mustang, Ford factory re-built 302 with 10,000kms on it. It was married to a C4 transmission. I have the new 302 ready to go into the 83 F-150.
Here is the riddle I can't solve:
- The new motor was on a C4. We have a C6.
- I removed my flywheel & mounted it on the new motor (took off the kid's C4 flywheel).
- Now I see that our larger C6 flywheel has a counterweight welded to it.
Then I realized that, oh yeah, that has a purpose I bet.
- We marked the flywheels but didn't mark the engine / TDC location to relate to the flywheel mark
- I was told to mount the larger C6 flywheel using blue loctite & torque to about 125lbs.
where do I mark / locate the counterweight on the C6 flywheel on the new 1986 302?
We are replacing a dead 302 with a kid's killer Mustang, Ford factory re-built 302 with 10,000kms on it. It was married to a C4 transmission. I have the new 302 ready to go into the 83 F-150.
Here is the riddle I can't solve:
- The new motor was on a C4. We have a C6.
- I removed my flywheel & mounted it on the new motor (took off the kid's C4 flywheel).
- Now I see that our larger C6 flywheel has a counterweight welded to it.
Then I realized that, oh yeah, that has a purpose I bet.
- We marked the flywheels but didn't mark the engine / TDC location to relate to the flywheel mark
- I was told to mount the larger C6 flywheel using blue loctite & torque to about 125lbs.
where do I mark / locate the counterweight on the C6 flywheel on the new 1986 302?
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From: nc
302 C4 swap for C6: Flywheel counterweight
are you working with the same imbalance on the two engines. you didn't state the year of the 302 that the c6 was bolted to. if the 302/c6 combination is an older model the imbalance will be different from the 80's model that the c4 was bolted to. 
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From: united states
302 C4 swap for C6: Flywheel counterweight
Teschwab is right, after 82 the 302 used a 50.oz balance flexplate where the earlier model used a 28.oz. Call Summit racing 1-800-230-3030 tech line and they should be able to tell you whick flexplate will work with youe engine and tranny.
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302 C4 swap for C6: Flywheel counterweight
I am not sure of the old 302 (I called the old owner & left a message). It was originally a 5.8L & someone put in this 5L.
Our C6 flexplate matched up perfectly with the 86 302 that had the C4 flexplate on it.
i sure appreciate you guys helping me. I'll be back.
Our C6 flexplate matched up perfectly with the 86 302 that had the C4 flexplate on it.
i sure appreciate you guys helping me. I'll be back.
Laughing Gas
Joined: Apr 2001
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From: Elon, NC
302 C4 swap for C6: Flywheel counterweight
>Our C6 flexplate matched up perfectly with the 86 302 that
>had the C4 flexplate on it.
Just a word of caution. These flexplates will "match up perfectly", but if you have the wrong imbalance you'll shake that engine apart!!
The other posters were right, check with someone like Summit Racing, they can tell you which one works.
Good luck,
Ron
>had the C4 flexplate on it.
Just a word of caution. These flexplates will "match up perfectly", but if you have the wrong imbalance you'll shake that engine apart!!
The other posters were right, check with someone like Summit Racing, they can tell you which one works.
Good luck,
Ron
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From: nc
302 C4 swap for C6: Flywheel counterweight
the 5.8 has a different imbalance than the 82 and later 5.0.match the flywheel to the engine i.e 86 engine and damper need a flywheel for a 86 engine. refer to a shop manual for the torque specs.
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From: Oregon: Land of the Majes
302 C4 swap for C6: Flywheel counterweight
Is the C-6 tranny all you have available? the C-6 is a bulletproof tranny, but drags a minimum of 66 horsepower off of the crank(subject to revision), so don't expect to get a drag racer out of it....I hope it all goes well.
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302 C4 swap for C6: Flywheel counterweight
We do have the C4 sitting there, but all I wanted was a Sudnay truck, we wanted to use it to haul our next project home 
That's why we thought that the C6 would be fine.
I think we are more into stock & stable than customized & fast on this one.
That's why we thought that the C6 would be fine. I think we are more into stock & stable than customized & fast on this one.
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302 C4 swap for C6: Flywheel counterweight
What a minute.
The flywheel is used to balance the engine?
That's what the harmonic dampner does.
The dampner has to be the correct weight for sure.
The counter weight on the flywheel is only a small piece there to balance the flywheel itself.
The flywheel weight is no where near the 28 or 50 ounces of the harmonic dampner.
The flywheel just needs to be bolted back into place.
The flywheel is used to balance the engine?
That's what the harmonic dampner does.
The dampner has to be the correct weight for sure.
The counter weight on the flywheel is only a small piece there to balance the flywheel itself.
The flywheel weight is no where near the 28 or 50 ounces of the harmonic dampner.
The flywheel just needs to be bolted back into place.
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From: nc
302 C4 swap for C6: Flywheel counterweight
bryan the damper and the flywheel work together to acheive the proper imbalance. the damper( harmonic balancer) also helps cancel out the bad vibrations that stem from the crank shaft rotation. now the small ford is externally balanced, but not all engines are set up that way some are internally balanced.
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