What am I missing here?
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Bigger is always better for damping purposes.
Yea I rolled with the 8" one. Who knows, maybe the ignition timing has never been where I thought it was! Doubtful, but maybe i'll pick up a little power if that is the case. I did notice it moving around a little a while back. One day it would be 24 and the next it would 35 but I honestly thought the distributor was cheap and messing up.
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Power, no. longevity yes,
Power would come from accurate timing and the damper it self is just the reference point. A solid repeatable reference goes a long way to dialing it in.
Power would come from accurate timing and the damper it self is just the reference point. A solid repeatable reference goes a long way to dialing it in.
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When you get the balancer take a dremel (or chisel and hammer) and make a notch between the outer and inner balancer.
First make sure 0 on the balancer/pointer is actually 0. Once thats confirmed then you can make the notch. Then install your timing tape.
If the new one ever rotates you will be able to tell quickly. For some reason most balancers are not manufactured with a notch. One area to save on cost.
First make sure 0 on the balancer/pointer is actually 0. Once thats confirmed then you can make the notch. Then install your timing tape.
If the new one ever rotates you will be able to tell quickly. For some reason most balancers are not manufactured with a notch. One area to save on cost.
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A paint pen is much faster for that.
Something to look at, if the old one has indeed delaminated and spinning, pay close attention to the crank keyway for damage, the crank hub OD, and the new damper ID, you need around .002-.003 interference, Hone as needed.
Something to look at, if the old one has indeed delaminated and spinning, pay close attention to the crank keyway for damage, the crank hub OD, and the new damper ID, you need around .002-.003 interference, Hone as needed.
Doesn't matter what the balancer says if timing is right.
For your dragstrip comparison to others though, I doubt your 5.3 friends are limiting themselves to 6k. Do they also have AR5 or T56?
If you shift your AR5 @ 6k, the fallback on paper after the 1/2 shift is 3616rpm.
If you shift your AR5 @ 7.5k, the fallback on paper after the 1/2 shift is 4520rpm (25% more combustion events vs 3616)
If you shift a WR T56 @ 6k, the fallback on paper after the 1/2 shift is 4242rpm (17% more combustion events vs 3616)
If you shift a WR T56 @ 7.5k, the fallback on paper after the 1/2 shift is 5303rpm (47% more combustion events vs 3616)
Rpm drop after the shift also affects the amount of rotating assy inertia that gets dumped and then has to get paid back. If you are letting off the throttle for the shift, a 6k shift dropping to 3616 after the shift represents a 64% discharge of stored inertia energy. With a WR T56, a 6k shift only discharges 50% of the rotating assy's inertia. That's about 14% less inertia discharge during the shift. The less energy you discharge during the shift, the less you have to pay back. Also the less energy you discharge during the shift the less likely to spin the radials, and if you do chirp the radials you will waste less power doing so.
Your 13.99 SLR with the AR5's 3.75 1st gear ratio isn't helping either. Since the engine will accelerate at a much quicker rate with a AR5's 3.75 1st gear vs a WR T56's 2.97 1st gear, the engine's torque output with the AR5 will be less. In the end the added multiplication doesn't get you anything, while the wider gear spreads cost you higher energy discharges that then have to be paid back.
Grant
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Great info! Thank you
Maybe I’m thinking of this wrong, but wouldn’t marking the pulley attached to the center of the balancer and then marking the outer ring of the balancer be the same as marking the center of the balancer?
The pulley is attached to the center of the balancer, but not the outer is the way I’m thinking of it. So if the mark on the pulley attached to the center, is off from the mark on the outer ring of the balancer, it would be the same as if it were actually marked on the center, correct?
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If the outer ring is slipping then there are two problems.
- First is the obvious that you can use the time marks to time the engine since this is the only external reference to where TDC for number 1 and number 6 are located, six being half way through the 720 degrees in the 4 cycles of an Otto cycle engine.
- Second is no damping of crankshaft vibration is occurring. This can lead to serious bearing damage which can lead to loss of the engine. The factory style bonded outer ring damper is functionally dependent upon the give across the rubber bonds to soften or damp the crank vibrations introduced through the hub. The rubber bond allows the outer ring to slightly deflect as it rotates the deflection allows the amplitude (amount) to be softened as it’s introduced to the outer ring and it slightly time lags. The ring as it returns introduces another vibration back through the bond through the hub to the crankshaft that is lesser in amplitude and off the frequency slightly. This is used to prevent the forces on the crankshaft that introduces these vibrations from becoming synchronized which would build even larger deflections in where and how the crankshaft is finding its own center of rotation. If the center of rotation is different than the center imposed by the bearings the difference becomes wear on the softer bearings.
Now if the ring appears to move under timing light surveillance this can be a function of ‘slop’ in the chain of parts that make up the cam drive system and the distributor drive system. Anything in that linkage of gears and chain turning the cam, flex or breakage of the camshaft which includes how it moves in thrust, the mesh of the cam‘s distributor/oil pump drive gear to the distributor’s driven gear. To some extent perhaps oscillation of the pump drive system as well may contribute to unstable ignition timing. Then all the contents of the distributor itself of main shaft, its gear attachment that is a roll pin, the shaft bearings and bushings, the stability and fits of the reluctor wheel and the stability of the module and its mounting.
So ‘slop’ anywhere in the chain of parts as described in the above paragraph can make it look like the damper’s ring is moving when in fact it is not. I guess this is a good spot to introduce the possibility that the timing light itself is in consistent. In the end you’ve got to chase these possibilities down one at a time. Plus in your case you need to track down and vibration effects the blower might introduce to the crankshaft, the blower takes a lot of power to drive so it can have considerable back effect on the crank.
Bogie
Well, ****. I would assumed the above photo was concrete evidence that the balancer was spinning around the rubber, but i'll remove the accessory drive system and mark the balancer the way johnson grass described. Without a water pump spinning I won't be able to run it very long, but it seems to be very quick to present itself.
To be a little more discriptive. The timing stays rock solid whereever it reads. Meaning if it jumps to 15 degrees as observed from the timing light, it will stay right there. Even under light throttle it will stay there. It's only when I really slap open and closed the throttle linkage that it moves on the balancer.
To be a little more discriptive. The timing stays rock solid whereever it reads. Meaning if it jumps to 15 degrees as observed from the timing light, it will stay right there. Even under light throttle it will stay there. It's only when I really slap open and closed the throttle linkage that it moves on the balancer.
I'll check it again, that is how I marked it.
I looked at that pic again and see the marks now. It looks like it moved.
I give up!!!! Lol
I was letting it run at idle just checking everything and it started smokig out of the tailpipe. First it was coming from just the passenger side, now both sides. Pretty steady stream of smoke. Hard to tell the color. Hard to really smell it too. Gunna wait until it cools down and pull the plugs. Maybe I just fuel fouled the spark plugs.
I was letting it run at idle just checking everything and it started smokig out of the tailpipe. First it was coming from just the passenger side, now both sides. Pretty steady stream of smoke. Hard to tell the color. Hard to really smell it too. Gunna wait until it cools down and pull the plugs. Maybe I just fuel fouled the spark plugs.
Definitely oil best I can tell. I cleaned the plugs up and put them back in. Still smoked. Didn’t let it run long enough to coat the plugs again. But I did check them with a spark plug tester and they are firing fine. I ran a quick compression test and they were all 145-150. I know that doesn’t test the oil rings of course.
Its a pretty constant smoke at idle. Haven’t driven it yet. I wish there was a good way to check oil rings versus valve stem seals. The constant smoke has me worried. It would be pretty weird to have the oil rings just fail all of the sudden, though. If it were a ringland I would suspect it to show up on a compression test. Valve guides definitely could be an issue as well. I just don’t know if any good tests to determine between them. Could be intake gasket too I guess. I’ll check the PCV system tomorrow also.
Pretty bummed. The motor hasn’t smoked at all since I built the motor. Just happened out of no where.
Its a pretty constant smoke at idle. Haven’t driven it yet. I wish there was a good way to check oil rings versus valve stem seals. The constant smoke has me worried. It would be pretty weird to have the oil rings just fail all of the sudden, though. If it were a ringland I would suspect it to show up on a compression test. Valve guides definitely could be an issue as well. I just don’t know if any good tests to determine between them. Could be intake gasket too I guess. I’ll check the PCV system tomorrow also.
Pretty bummed. The motor hasn’t smoked at all since I built the motor. Just happened out of no where.
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You need to get down to whether it’s oil, fuel or coolant.
Valve guides and stems can be a problem on blower motors where intake manifold pressure is blowing what little oil gets in the guides back out.
Bogie
Valve guides and stems can be a problem on blower motors where intake manifold pressure is blowing what little oil gets in the guides back out.
Bogie
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