Thanks to a good deal and a very understanding wife, I am the proud new owner of a fresh 69 428CJ motor. The PO bought this motor out of Canada in 09 for a project that never happened. I asked him of it had been balanced and he said yes. There is no fly wheel or flex plate with this motor. The crank has a thin balancer/pully on the front. No damper. I can tell the rod caps have been gound on and the pistons look like they have material removed as well. Crank does not appear to have had any heavy metal/mallory added but does have drill holes. So my delima is what should I do about a damper and fly wheel/clutch/pressure plate?
428 CJ balanced, but which way internal/external
tommyjack
1 - 10 of 10 Posts
Thanks to a good deal and a very understanding wife, I am the proud new owner of a fresh 69 428CJ motor. The PO bought this motor out of Canada in 09 for a project that never happened. I asked him of it had been balanced and he said yes. There is no fly wheel or flex plate with this motor. The crank has a thin balancer/pully on the front. No damper. I can tell the rod caps have been gound on and the pistons look like they have material removed as well. Crank does not appear to have had any heavy metal/mallory added but does have drill holes. So my delima is what should I do about a damper and fly wheel/clutch/pressure plate?
Joined
·
1,993 Posts
If you feel lucky, slap a 428 flywheel on it and try it.
Make sure it is for a fact a 428 crank, 1U, 1UA, 1UB, and if there isn't any Mallory metal in it, odds are it will be very close
Make sure it is for a fact a 428 crank, 1U, 1UA, 1UB, and if there isn't any Mallory metal in it, odds are it will be very close
Joined
·
1,993 Posts
A 428 with a 1U crank only has weights on the flywheel not the balancer.
All FEs use neutral balanced balancers, only the 1UA crank SCJs use a counterweight on the balancer spacer, but still use a zero balance balancer
Use a 390 balancer and spacer, and buy a clutch/flywheel/bell to fit a 428 car.
All FEs use neutral balanced balancers, only the 1UA crank SCJs use a counterweight on the balancer spacer, but still use a zero balance balancer
Use a 390 balancer and spacer, and buy a clutch/flywheel/bell to fit a 428 car.
Joined
·
1,993 Posts
One other thing thing a CJ car will have a big in/out tranny. So if its your car that you have the C in now, buy a 428 flywheel, but be sure the clutch is for a small input tranny like a 351/390 uses, the 428 clutch will have the big 1 3/8 x 10 spline and wont work
I cant change my signature for some reason. This car is a 69 S code Mach with a 67 GT 390/4spd with only about 100 miles on a complete rebuild. Since it is not original I have no heart break about swapin in a CJ. I'll keep the 4spd so I will need to get a 428 CJ fly wheel, plan on using the 390 pressure plate and up grading to a cermaic type disk for a 390. Later on I'd go like you did with TKO. Sounds like you have a nice ride.
Hi TJ,
Something comes to my mind here...........you can balance an engines internals (to each other) such as the pistons, rods, etc so the weight is similiar to the same components, but....without the flywheel/flexplate & dampner, the engine rotational assembly cannot be balanced.
IMHO, I think I would consider pulling the crank and having the assembly actually balanced. It;s cheap insurance IMHO,
Something comes to my mind here...........you can balance an engines internals (to each other) such as the pistons, rods, etc so the weight is similiar to the same components, but....without the flywheel/flexplate & dampner, the engine rotational assembly cannot be balanced.
IMHO, I think I would consider pulling the crank and having the assembly actually balanced. It;s cheap insurance IMHO,
Joined
·
1,993 Posts
Beechkid, you aren't wrong, but, if at that point you dont pull a piston and rod combo to weigh the rotating/reciprocating weights, its still a WAG.
The absolute right way is to pull a head, disassemble a rod and piston, weigh, calculate bobweights and spin the crank again with all the parts
However, odds are, if it wasn't internally balanced, its closer now with a generic 428 wheel bolted to it than it ever was from the factory.
The absolute right way is to pull a head, disassemble a rod and piston, weigh, calculate bobweights and spin the crank again with all the parts
However, odds are, if it wasn't internally balanced, its closer now with a generic 428 wheel bolted to it than it ever was from the factory.
Any recommendations on cam specs? Want to go either solid or roller, max out RPMs at 6-6500. Car will have a TKO tranny, 3.91-4.11 rear. 175hp shot of NOS is not out of the question. Street/strip car, well mostly a strip car thats driven on the street.
1 - 10 of 10 Posts
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
