Vac pump destruction / mystery

[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

[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....

[joespanova]

OK...........I understand your "timing" points. I've run less , but it does in fact , fall off..................just for shyts and giggles I'll pull it down to 34 and see what happens........
Besides all this........I have to follow up with this closing comment.
I made the mistake of using the Brad Penn BREAK IN oil to make initial passes down the track ( 5 ) , no one ever warned me or told me otherwise..........call me a dumazz if you want , but I did, and I learned the hard way. My INTENTION WAS , run it a few times and change it.
Now , I know that was wrong..................perhaps the vac pump isn't the problem now , after all. I actually called Brad Penn and talked with "Ken?"
anyway he slammed me for doing that , so did my "old machinist" I use.......LOL
And Adger Smith made references to this as well.......the older I get , the dumber I still am........doubt timing contributed.

[buzzinhalfdozen]

I've personally made many passes with BP breakin oil in my engine, never had an issue with mine or the several engines I've freshened for other racers. Not sure that theory holds water, however the timing advice sounds like a likely cause. Hope you find it. BTW on the engines I've done for other folks , with a wet sump and vacuum pump I "request" they not pull more than 10 inches. That number is NOT a result of much R&D merely going off the condition of engines at tear down with a known amount of vacuum.

[1320racer]

Originally Posted by joespanova

Ya' know............I've had more oil starvation problems in the last few years than probably 10-20 guys combined.
Lost 2 engines in 15 years....meaning blocks and some other hardware.
Even now , with my new Dart block , the main AND rod bearings look like sheeeot........... Nothing is damaged but the bearings will have to be replaced. I currently have a new Lunati crank.........this is no cheapo' either.
The one common denominator in every engine has been the vac pump.
I currently use a STD. volume "Moroso" melling OEM style pump ( modified by Moroso ) and a new pan. But it doesnt matter what I use.......I still have oiling problems.
Bearing clearances are .0025- .003 ( thats not per side , thats total ).
The vac pump with the regulator "out of the box" regulated down to the lowest setting still pulls 15" in high gear thru the lights. I've read on other web sites " Yellow Bullet" where plenty of guys are running 18-20 inches ( all wet sumps ) and not having issues. External pumps , accumulators......I have no idea......but I don't believe they all are. How they are getting away with that is beyond me.
Soooo............the vac pump must go. Its effectiveness ( if any ) is being waaay over shadowed by the destruction it causes. If I drop it down to say 10 inches......I would be just as well off using crankcase vents.Super Stock engines can't even use them.........apparently they innovate some creative PVC system .......but I was concerned that would introduce some oil into the intake.......so , I'm not doing that. RPM range is 87-8800.
Can I hear some opinions on this ?

My engine builders would say your vacuum is too high.

Originally Posted by joespanova

I made the mistake of using the Brad Penn BREAK IN oil to make initial passes down the track ( 5 ) , no one ever warned me or told me otherwise..........call me a dumazz if you want , but I did, and I learned the hard way. My INTENTION WAS , run it a few times and change it.
Now , I know that was wrong

dumazz

That said, making passes on break in oil is not your issue, many have including myself though not on brad penn, personally I would never use it, don't like what I've seen come out of friend's engines who run it. I've broken it using Joe Gibbs or Lucas and run Mobil 1 in my race engines for the past 25 years.

Otherwise, hope all is well.