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THREAD KILLER
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never did a sbf that extreme but on the chevy stuff we just use clevite H's with the trailing edge of the upper and lower shell's beveled to pressure feed the thrust side.
 

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Drill a small hole on the side of the lower main through the bearing. This keeps oil pressure between the thust bearing and cap. I haven't had any thrust issues in 15 years doing this with blowers and turbos. Good luck.
 

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Drill a small hole on the side of the lower main through the bearing. This keeps oil pressure between the thust bearing and cap. I haven't had any thrust issues in 15 years doing this with blowers and turbos. Good luck.
Do you happen to have any photos of this little trick?
 

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60psi by-pass valve on the trans cooler line .
Got any more info on something like this? It's been coming up in my searches recently. I'm killing thrust bearings now myself.
 

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Discussion Starter #9
Bypassing the pressure on the cooler line circuit. If you have 120+ psi on the line and you cut it down to 60 you have half the hydraulic force pushing it forward
 

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Drill a small hole on the side of the lower main through the bearing. This keeps oil pressure between the thust bearing and cap. I haven't had any thrust issues in 15 years doing this with blowers and turbos. Good luck.
PM this guy ^^^^^^ he knows what works
 

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PM this guy ^^^^^^ he knows what works

The converter pressure should be addressed along with the bearing mod .

I did the bearing chamfer mod on mine ,

Also check the pilot on the converter . Make sure it doesnt bottom out in the crank .

I found that mine didnt bottom out but the lip on the crank was actually too close to the converter .. . We cut the crank back to get the proper clearance .

This was an Eagle 4340 for SBC .
 

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Correct converter spacing and a tuneup that will jump up on boost/converter go's a long ways to not having any issues. If it takes longer than about 3sec to get up on launch boost I would re-evaluate my converter and tuneup. We did a pressurized thrust bearing a lot when I was at KUP and it was very reliable. The needle bearing thrust is a bit more evolved but seems to work very well too. As far as specific mods to a SBF, Pete at HED has posted on here that they were lilting thrust bearings all the time and he switched to ACL bearings and never hurt another one. All bearings are not created equal.
 

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My SBF chewed up the thrust and got into the crank about .040 after only 1000 miles. I was running a C4 trans, and I never knew to check the clearance between the convertor and flex plate, but I know I had a gap there. My tuner said to do the Torrington bearing, and thats what Im planning to do. Im also ditching the C4 and going to a AODE.

I was also told about doing the Relief Valve on the trans line. I wish someone had some pics of how this is done. I plan to do everything possible to eliminate this from happening again.
 

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If you want you can pressure feed the bearing. Put a small groove in the block it self from the oil feed to the rear of the thrust, then cut a small channel to each side of thrust area in either the bearing or block, then drill two small bleed holes say maybe .030 at most in the bearing it self to allow the oil to come through the bearing.
 
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