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cj5.5
09-13-2007, 03:24 PM
I had a 304 which was shot in every sense of the word. I ordered a 360 block and used my crank and rods based on the casting numbers they will work. The pistons are balanced so my question is can i use my old flywheel and harmonic since they where already on that crank to begin with. I should have taken pic's because now I have questions on puting it back together. Question 1 with the rockers torqued would you say that the lifters are slightly depressed or should they be at the up postion. They look like they would only depress all the way then come back up to half. The rods will still spin with your fingers just not sure. Question 2 on mounting the fly wheel back on does it need to line up in some way sense it is balanced. Thanks to all who reply. This has been an 8 month project and 6 trips to the machine shop for everthing going wrong. I look to try to finish this weekend motor willing.

tufcj
09-13-2007, 06:00 PM
The 360 pistons most likely don't weight the same as the 304 pistons. The 304 Flywheel/harmonic was balanced to the weight of the 304 pistons, therefore you should have the entire rotating assembly balanced for the weight of the new pistons. Balancing is worth the money, the engine will run smoother and last longer.

The flywheel/crankshaft has one bolt hole that is slightly out of alignment, there is only 1 position where all 6 bolts will go in.

The plunger in the lifter should be depressed slightly (around .020") from the keeper with the lifter on the base circle of the cam (valve closed). If the plunger isn't depressed, you may need a longer pushrod. As long as the heads haven't been seriously milled, chances are you'll be fine with stock length pushrods.

Which heads are you using? The 304 heads have smaller valves than the 360. If you're using 304 heads, check the valve/piston clearance, since the valve reliefs in the pistons won't be correct. You also won't get the best performance out of your 360 with 304 heads, AMCs need to breathe.

Bob
tufcj

cj5.5
09-13-2007, 06:24 PM
The heads are off a 360 with some kind of performace job. The 304 block was ovaled at the top. The machine shop said they do a little different on performace heads and was not sure why the heads were in the condition when taken off the 304. I am not sure if that was good or bad. But they did rebuild them. Only problem was the do not balance motors and they grinded my crank down .03 and the 304 block was over .60 and some. Since the engine is all together will it need to be tore down to balance. Any recomendations on a local flywheel. Like autozone napa advanced. Thanks

tufcj
09-14-2007, 07:25 AM
You could get a 360 Flywheel/harmonic to avoid tearing it down. It won't be as good as a balanced assembly, but closer than the 304 parts.

You can look on ebay. 360 flywheels are always out there for about $125 + ship. Check with www.fastengineparts.com (they sell as HD_MAD_DOG on ebay) for a harmonic, they are being reproduced.

You could PM jeepsr4ever here, and ask him what kind of prices he can get for the flywheels and harmonics, I know he can get them, even if they're not listed at the E-store.

Bob
tufcj

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