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428 Flywheel Issue, internally or externally balanced??
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Hello guys, happy holidays! I'm half way thru a Factory Five build and plan to install a motor that I bought on craigslist a year ago. As advertised, rebuilt 428 with receipts and paperwork. It does not have a flywheel or clutch and pressure plate so that's where I'm stuck.
The question, this motor was balanced during the rebuild, but I understand that "all" 428 are externally balanced, which flywheel? I'm stuck! I don't know which crank, etc, this motor has so the next step is tough. Pictures attached......and thanks in advance for any help. |
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pictures of the build receipts below......
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First q... Can you contact the guy you bought it from?
If not, it looks like there's a counterweight bolted to the back of the damper or is that the backside of the damper? Can you get an inspection mirror and verify? Or... contact Johnson's Machine like it says on the invoice and ask them. Most balancers keep electronic records. We can go from there... |
Either the motor was zero balanced, or it was balanced with a 428 flywheel. You weren't provided one? Even with a zero balanced motor, the flywheel needs to be part of it. Surely the seller knows. Good luck, Bill.
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Crank
There were 2 differrnt 428's ... passsnger nlock and yhe SCJ which was ballanced with a external weight on the crank behind the balancer. The only way to know is to find out which crank the motor has. Pass crank's are 1U or 1UB and are internally balanced. Pull the pan to find iut what u have...
Jon |
Not to be rude but it doesn't really matter what the motor was originally. You can have an externally balanced motor balanced internally. Yes, he can pull the pan and check for mallory metal on the counterweights, but me personally... I'd rather make a phone call.
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My guess is that it's still externally balanced. My reasoning is that it takes multiple pieces of heavy metal to internal balance a 428 crankshaft. I would think that would have been noted as it's $$$.
HOWEVER.... There's no way of knowing for 100% certainty unless you pull the oil pan or contact the shop that built the engine. Unless it's a SCJ, all FE's use a zero balance harmonic balancer, so you can't tell by looking at the balancer. If it is a SCJ, there's a big fat hatchet weight hanging off of one side of the balancer spacer. My vote is to call the shop. If they don't know, get it up on a stand, drop the pan and post pictures of the crank counterweights. |
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Happy New Year guys. I finally had time to pull the pan after the holidays. The crank is a "1U" as noted I n the pictures attached.
Guess this means the motor is "internally" balanced? |
With the above information I have 4 quick questions-
1) would love a quick revving 18lb aluminum flywheel, but would I regret not getting a 30lb steel given its smoother driving? 2) Should I go with the McLeod flywheel, pressure plate and clutch? Which diameter? 3) What horsepower might I expect from this build? a) as is, with stock heads, Holley 750 DP, comp 270h cam, etc... and what's a safe RPM? b) adding my Edelbrock heads, comp 274h cam, Harland Sharp roller rockers, same Holley 750DP carb, etc....and what's a safe RPM? Thanks in advance! Blaine |
Not internally balanced
Hi Blaine,
That doesn't mean it is internally balanced. It means it isn't a 428 SCJ, so you don't need to run the hatchet spacer behind the balancer. You still need to run the 28oz inbalance flywheel, and to be safe, you should contact the engine builder. BTW, I'm running an aluminum flywheel, and I like it. |
I'm no expert on these things but you might post a close up of the holes drilled in the crank in the last photo so someone can tell if any of them have Mallory in them. Safest bet is still to talk to the machine shop or builder directly.
Keith Craft suggested a 18 lb aluminum flywheel and standard 12 inch clutch , all from McLeod for my car and I love the way it revs. I noticed the other day that the 11 inch clutch is rated a slightly higher clamping pressure than the 12 inch - probably to make up for the lesser friction contact area. So both (11 and 12 inch) probably have about the same capacity. Possibly the slightly lower clamping pressure of the 12 inch might relate to a slightly softer clutch pedal effort - but if so, not by a lot. Blykins might be able to recognize some of the parts on the engine and give you a ball park est on HP. I know from my visits to Keith Craft that most of his blueprinted completely stock CJ motors made about 415 HP. But from the above I don't know what steel heads and intake you have, what compression pistons and you have an aftermarket cam. Getting some part numbers off the heads, looking up the cam and piston specs and an ID of the intake might help some. A lot of variables including the skill of the assembly guy and getting it dialed in once it's running. |
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For answers
I would go to the Ford fe forum or contact Survival motors, Brent ...craft Racing these shops build FE motors all the time
Jon |
Hmmmm.....blykins do you have a further opinion?
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1U is a 428 crank. I don't see any heavy metal in your crank, so I would assume it's externally balanced.
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