Vac pump destruction / mystery

[joespanova]

Originally Posted by MAURICE BLENDHEIM

Your 60lbs. oil pressure. Are you taking your oil pressure reading from the rear or the front of the block? MB.

Thank you all for replying , trying to help out BTW...
I take oil pressure off the rear of the block.
Every single bearing had trash in it..........I'm actually beginning to doubt the pump is the problem myself................hell , I dunno..........I mean , its not like I haven't put plenty of engines together over the years. I've actually had these engines ( in the race car ) apart over the years and the bearings come out looking great , also...........so as the thread states , this is a "mystery" to me.
Some of you may recall I have lost oil pressure even in this new block , pulled it down and found all the main bearings were completely destroyed .as well as the center main caps on a brand new Dart block.
Please look thru this thread..........realize the vac pump is the common denominator.
http://classracer.com/classforum/sho...t=61697&page=2

[monte442]

I've seen bad finishes on crank hurt bearings. Was every plug and all cam bearings removed from the block when it was cleaned,was it cleaned with brushes in all of the oil galleries ? Are all of the oil pump mating surfaces true and clean ,pick up welded and sealed to pump ? If it is pumping aerated oil through the system it will never maintain an oil wedge between the crank and bearings.

[CFMCNC]

Center main caps ,Detonation ,very high cylinder pressure trying to push the crank out the bottom.Most bearing failures are from missed tune .Bill C.

[joespanova]

Originally Posted by CFMCNC

Center main caps ,Detonation ,very high cylinder pressure trying to push the crank out the bottom.Most bearing failures are from missed tune .Bill C.

Missed tune...........I sure hope not. At 355 inches , std port 23 degree heads N.A. and 3000lbs to run a 9.41@142 I must be doing something right , anyway.
No I'm not beating my chest here either..........

Total timing never more than 40 , 2 660's textbook jetting........etc etc

[CFMCNC]

Track performance is very impressive,Has the engine been on engine dyno?.Bill C.

[joespanova]

Originally Posted by CFMCNC

Track performance is very impressive,Has the engine been on engine dyno?.Bill C.

Thank you.......and "sometimes" it is ,anyway.
Actually running a .60 anything is disappointing now.....
No on the dyno........I would guess around 630-640 using readily available formulas.
I'm going to solve this .........once and for all , before it even gets back in the car. I swear / hope.............lol

[RJ Sledge]

Although my application was a Stocker, low to mid ten Ford small block, I had the same problem after about 5 or 6 passes. I had set my oil pickup clearance too short and it was starving my bearings. Set it to .400 and I never had any more problems. You can get it too close.
Sometimes its the little things you can take for granted.

Hope you figure it out.

An Accumulator can also help.

RJ

[joespanova]

Originally Posted by RJ Sledge

Although my application was a Stocker, low to mid ten Ford small block, I had the same problem after about 5 or 6 passes. I had set my oil pickup clearance too short and it was starving my bearings. Set it to .400 and I never had any more problems. You can get it too close.
Sometimes its the little things you can take for granted.

Hope you figure it out.

An Accumulator can also help.

RJ

Thanks.......great point. Mine may be a little too close too @ .250ish. or less even
The only way to fix is to take a 2x4 and wack the pan bottom a little.

[Ed Wright]

Originally Posted by joespanova

Missed tune...........I sure hope not. At 355 inches , std port 23 degree heads N.A. and 3000lbs to run a 9.41@142 I must be doing something right , anyway.
No I'm not beating my chest here either..........

Total timing never more than 40 , 2 660's textbook jetting........etc etc

A 350" with 40 degrees?? Looks like CFM was right. I have never seen a 350" need more than 34 to 36. Sounds like detonation to me.

[Rich Biebel]

Can you verify that oil pressure is never lost during a run ? You could use a go-pro camera and focus on the gauge....poor mans Racepack...
Did you ever consider using an Accusump...to help maintain pressure in case it drops?



Timing is to high and could be knocking the bottom end out of it...detonation as Bill C. mentioned will kill any engine...
No reason to be that high...... a small cube engine with giant domes in small chambered heads in a heavy car might like 40-42 degrees but not for long if it detonates...

That engine sounds like an old school modified engine.....2-660 carbs....

8800 rpm is a lot......and hopefully has titanium valves and the best valve train pieces to be reliable....