Destroying thrust bearings
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From: jefferson city MO
Destroying thrust bearings Hello guys going to need little help with with this one
My combo is
Engine is on pump e85
365ls/lq9, lunati pro series crank,lunati pro ibeam rods, wiesco pistons.
trick flow 255 heads solid roller cam.
main bearing clearance was .0033 on mains and .0028 on rods. thrust was at .005. block was line bored, and square deck.
I drill rear thrust bearing with a 1/16 hole directly into oil galley of the bearing to force feed oil to thrust surface.
Twin 62/66 precision turbos set at 28.3 psi at full boost.
4l80e with d3 trans brake built for 1500hp+- pro yank 3400 stall
The car has went 9.3 @ 147mph with 1.4 60ft leaving the line at 3600rpm 7psi.
boost peaking at 14.8psi(just a few shake down runs with this combo)
Boost is now set at 28psi, have not been back to track yet before engine was hurt
Oil pressure dropped when car was on dyno 2weeks ago. pulled apart and found rear thurst metal to metal.. crank was moving .021 front to back.
What can i do to stop this from happening?
Thanks guys
My combo is
Engine is on pump e85
365ls/lq9, lunati pro series crank,lunati pro ibeam rods, wiesco pistons.
trick flow 255 heads solid roller cam.
main bearing clearance was .0033 on mains and .0028 on rods. thrust was at .005. block was line bored, and square deck.
I drill rear thrust bearing with a 1/16 hole directly into oil galley of the bearing to force feed oil to thrust surface.
Twin 62/66 precision turbos set at 28.3 psi at full boost.
4l80e with d3 trans brake built for 1500hp+- pro yank 3400 stall
The car has went 9.3 @ 147mph with 1.4 60ft leaving the line at 3600rpm 7psi.
boost peaking at 14.8psi(just a few shake down runs with this combo)
Boost is now set at 28psi, have not been back to track yet before engine was hurt
Oil pressure dropped when car was on dyno 2weeks ago. pulled apart and found rear thurst metal to metal.. crank was moving .021 front to back.
What can i do to stop this from happening?
Thanks guys
I've had personally experience wih three combos this happened to and each time it was related to the driveline. Two were converted related, the third was the clutch.
With a combo like yours, I would run looser than .005", but it sounds like yours was damaged too quick to be an issue with the bearing or clearance.
With a combo like yours, I would run looser than .005", but it sounds like yours was damaged too quick to be an issue with the bearing or clearance.
If the bearing shells in the rods look like hell but the shells in the rod caps look good. Then detonation could have been causing major crank deflection
My guess is the converter is ballooning under the torque and when the pump drive bottoms out in the trans, the front side mashes the flex plate forward
A turbo/nitrous converter needs billet plating as they literally expand like a heart pumping. It's quite insane what they deal with
My guess is the converter is ballooning under the torque and when the pump drive bottoms out in the trans, the front side mashes the flex plate forward
A turbo/nitrous converter needs billet plating as they literally expand like a heart pumping. It's quite insane what they deal with
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From: jefferson city MO
Rod bearings almost look new all the way around. little trash went through them but def no detonation. The only bearing hurt was middle thrust bearing.
im thinking its converter related but dont know how to fix it or engine to make it live.
The car made 996ft tq at 4600rpm and 882hp at 5600rpm with the tires smoking on the rollers after 5800rpm.
I had 625lbs of people/weight sitting in hatch of car when this happened. Im thinking car should be in the 12-1300rwhp once back up and running on 28psi.
The boost number for this combo will be 32-35psi at track once cars dialed in.. need to fix this little problem first. thanks for the reply's so far guys.
im thinking its converter related but dont know how to fix it or engine to make it live.
The car made 996ft tq at 4600rpm and 882hp at 5600rpm with the tires smoking on the rollers after 5800rpm.
I had 625lbs of people/weight sitting in hatch of car when this happened. Im thinking car should be in the 12-1300rwhp once back up and running on 28psi.
The boost number for this combo will be 32-35psi at track once cars dialed in.. need to fix this little problem first. thanks for the reply's so far guys.
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From: Saskatchewan, Canada - where arguing "DA" is for the slow and weak...
As previously mentioned. Basically you need something like this to keep the converter from ballooning: http://www.torqueconvertershop.com/b..._converter.htm
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I had a restricted trans cooler with no over pressure protection in my th400... Kicked the converter out the front, Killed the thrust, counter weights started hitting the mains and it was rebuild time. That fresh engine lasted 70km lol 
One came back and the owner of the car was furious and thought we were at fault. We fixed it, even had the shop owner over my shoulder when I set the thrust and got .006-.008" for end play. It did it again. When it came back again, the guy apologized and admitted he found something wrong with the transmission. That's was the last I heard of it. Similar occurrences with the other two, both causes were traced back to the driveline, but I couldn't really say what they were. I was just repairing the engines.