[Kenth]

https://www.amesperf.com/parts/13651/

With all the talk about doing this and that with blocks and heads and god knows what, you're going to continue to build the engine with 7 pistons backwards?

[Jay S]

Every 9 way timing set from comp I have ever seen is designed so each key effects the cam timing by 2*.

-8*, -6*, -4*, -2*, 0*, 2*, 4*, 6*, 8*

I hope the cam was degreed in after the cam timing was changed. The 9 way timing sets are designed to changed the cam timing in 2* increments, irregardless of the crank turning twice as fast as the cam.

Sometimes harmonic balancers fail because something on the inside of the engine create’s an unusual stress on it. Could be having one piston in backwards contributed to the cracked hub.

[TRADERMIKE 2012]

Originally Posted by Jay S

Every 9-way timing set from comp I have ever seen is designed so each key affects the cam timing by 2*.

-8*, -6*, -4*, -2*, 0*, 2*, 4*, 6*, 8*

I hope the cam was degreed in after the cam timing was changed. The 9-way timing sets are designed to change the cam timing in 2* increments, regardless of the crank turning twice as fast as the cam.


Sometimes harmonic balancers fail because something on the inside of the engine creates an unusual stress on it. It could be having one piston in backwards contributed to the cracked hub.

The Gears were set to "no" advance to start, yes.


It sounds like you don't think that the Trans. accident that I had destroyed my TH 400. Due to running over a root, under a driveway, that caused an upward push under the Trans Oil Pan while the Engine was running caused a forward Thrusting movement to all the internal shafts in the Trans., carrying through to the Engines Crank shaft, then the Hub? Several people said that the Crank Harmonic Balancer Hub breaks at the key way often enough for other reasons. Since I don't know, I reasoned that this is how, in this case, the Hub became unusable.

Your theory is as good as mine. Being that I found the broken Hub after the Trans. rebuild and that it was after the accident in the garage running the vehicle is when I experienced the Ghost noise first and then again when I first began to test and tune the rebuilt Trans, I stick with moving on with fixing the locations that I have been convinced will do the best, in this case. For the last ten years I have been jumping over Hurdles trying to move past one problem or another, since they happen at different times I address them as so, one at a time. This fix is $600 having the Heads remanufactured, $210 in gaskets, some miss. items and next will be the new Hub or combination of a Hub and Harmonic Balancer, I found a respectable Billet unit for $210-$230.

$ 1000 is the limit for cash, at this time, I will take my chances and keep my fingers crossed. However, rite you are, in stating that I should rebuild the bottom end now, due keep in mind that the car has been off the road now for two years due to the Trans. rebuild. Time to save some more money, besides I am curious enough to find out whether or not I have correctly diagnosed the noise anomaly. I will squeeze the miles out of this Crank case, I am guessing I have at least 50k hidden usable miles to use, but who is to say I hope there is more.

[Stan Weiss]

Originally Posted by Kenth

https://www.amesperf.com/parts/13651/

With all the talk about doing this and that with blocks and heads and god knows what, you're going to continue to build the engine with 7 pistons backwards?

I have no problem with the pistons in backwards. I would turn the 8th one around (backward) make sure the rods are correct direction on the crank and call it a day.

Stan

["QUICK-SILVER"]

What is piston deck height on this project?

Pistons "look like" stock.

That 1/10th of an inch extra stroke should have pistons above deck with stock rods and stock pistons.

How was oil clearance on the rod bearings measured? And did the top half of the bearings get inspected?

The throws with .005" oil clearance are a bit much.

Given your location and engine temp problems... I would do some serious homework on SCR and DCR before running that cam advanced more than what's ground in.

And there's more
Clay

[TRADERMIKE 2012]

Originally Posted by "QUICK-SILVER"

What is piston deck height on this project?

Pistons "look like" stock.

That 1/10th of an inch extra stroke should have pistons above deck with stock rods and stock pistons.

How was oil clearance on the rod bearings measured? And did the top half of the bearings get inspected?

The throws with .005" oil clearance are a bit much.

Given your location and engine temp problems... I would do some serious homework on SCR and DCR before running that cam advanced more than what's ground in.

And there's more
Clay

We did not measure from the center of the Crank to the top of the Deck; however, the piston is flat in the center and we used a straight edge bolted down and placed a feeler gauge in between the TDC of the number one-cylinder Piston and found 0.035". This is from memory, when My roommate comes home, I will ask him, I am thinking a little more than that. So, the Piston is not past the Deck for sure. We are performing a cooling mod. while the Heads are off, theoretically netting us 10 - 30 degrees cooler, we will see. Here is the Oil Temp. results:

RPM 190 degrees 220 degrees
500 20 psi 15 psi
700 20 psi 15 psi
900 25 psi 20 psi
1000 25 psi 20 psi
1500 30 psi 25 psi
2000 35 psi 30 psi

You said:

"That 1/10th of an inch extra stroke should have pistons above deck with stock rods and stock pistons."

Considering this a stock motor, my roommate took measurements the best way he could, at the time. The rods are stock length.

Note: The Deck is not cut down, we know this because we can read the Piston letter code on each of the eight cylinders.

[TRADERMIKE 2012]

Originally Posted by Stan Weiss

I have no problem with the pistons in backwards. I would turn the 8th one around (backward) make sure the rods are correct direction on the crank and call it a day.

Stan

Perhaps that is my next project, this one is winding down, the machinist called today, wanting to know what vehicle my motor was in, so he can look up some parts. I told him to look up any 1967 Pontiac, that used the 428 ci Engine, HO was an upgrade option for all 1967 vehicles or so I read.