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Going back to the over rev issue. First thing is an ignition box with a soft rev limiter is a lot cheaper than buying a new motor or attempting to repair the old one.

The second issue is you need stouter valve springs (and probably a few valves), as you floated the valves so badly the rocker was able to turn sideways (another reason to buy shaft mounted roller rockers as they can not rotate on the stud), and let the push rod escape. I mentioned the valves as they in all probability kissed the pistons and could now be bent.

I run a BBC with 2.30" inch intake valves (it may sound huge, but they are actually small compared to my displacement). What they are is heavy and hard to control at high RPM. I have to stay on top of valve springs all the time and I consider them to an expendable just like filters and oil. It doesn't mean I skip on quality; I buy the best PAC alloy tool steel springs I can, but I still replace them as soon as they show 7% to 10% loss of pressure at installed height. I have learned that springs are cheaper than motors as well, and a big block just loves to eat valves.

Big Dave
 

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Discussion Starter · #22 ·
The valve springs came with the kit, so they are matched for the cam, also the rocker arm didn't slip off to the side, the pushrod went right through the cup in the rockerarm...It's actually pretty cool looking, never seen anything like it. I'd attach a pic to this thread, but I don't know how, or if I can.

I'm not getting a warm feeling about this, I've got good compression on all the pots, the oil pressure line is at the rear of the motor in back of the intake, and that seems to be intact, I removed the line and cut an inch off the end in case something was clogging it. It's got two piece covers on it so I guess I'll check the actual flow, and see what I'm getting.
Thanks big time
 
G

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i've heard that some oil filters will cause a loss/drop of oil pressure... particularly Fram units.

i don't know if this is applicable or useful to you though...
 

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i've heard that some oil filters will cause a loss/drop of oil pressure... particularly Fram units.

i don't know if this is applicable or useful to you though...
Fram has to be the worst ones. I had to change out the filter on my 355. It went from 65 lbs warmed up running 55 mph and 30 lbs at idle which is 900 to 5 lbs running 55 and 2 at idle. Changed out filter and right back to where it should be. :)
 

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Discussion Starter · #26 ·
My Big Mutha Thumper cam is HISTORY, so I guess the timing problem is a mute point. And just when I was starting to get it dialed in.
My oil pressure problem was solved when I dropped the pan down to change the oil pump, and found a big pile of gray goop in the bottom of the pan.
Seems the cam is self destructing because of the lak of "NITRATES" in my oil and it's wearing out the cam and main bearings slowly, hence the drop in pressure.
I HAVE TO GO PUKE
 

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Discussion Starter · #28 ·
Most of the crap is sticking to a magnet,
and a friend of mine that has made the same error as I in this matter, he said that what I see in the pan, is cam and main bearing particles. This explains why the lousy oil pressure after warm up. He also said that if I keep driving it, the crank will make a good boat anchor before the month is out.
I've got the motor just about out of the car now, and thanks for all the info, this site is a great attitude adjuster. Not to mention Tutorial...
The lesson here to me is, use the proper lubricants and additives for a cam break in, and oil additives going forward. You can bet I won't do this again....
 

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If you buy racing oil marked "not legal for use with catalytic converters" it will have the required ZDDP that you need to run a flat tappet cam. If you want to be able to pick up oil at any gas station/QuickyMart then you need to buy retro fit rollers and a roller cam.

Ever since Ed Iskenderian invented his series of Red Zone self lubricating solid roller tappets the cam grinders have all come out with their own version of self lubricating solid roller but not for the hydraulic roller tappet that most use (because a solid has a higher spring load to rev higher than a hydraulic can). A self lubricating roller tappet can be used on the street as easily as a solid flat tappet could be. The same grind cams that most would normally put in their hot rod as a hydraulic cam can be had as a solid grind.

Big Dave
 

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I have a suggestion for the next rebuild's break in of this engine. Recently JOE MONDELLO "DR. OLDSMOBILE" was on HPTV showing the guys how to properly build a HP 455 OLDS. One of his tricks was to use his Heat Seeker II-Engine oil additive to eliminate heat & friction during initial break-in of new performance engines. There may be other products out there like ROYAL PURPLE BREAK IN OIL but MONDELLO'S one caught my eye.
Seems that if one wants a HP flat tappet engine to live now days OIL SUPPLEMENTS will have to be used. I have even noticed that flat tappet B&S, TECUMSEH, KOHLER ETC. are not lasting as long now days. If you think auto engine parts are high $$. Try pricing small engine parts.
Lowering the ZDDP levels in most modern oils will be costly for the uninformed. Not only for their PRIDE & JOY but the everyday workhorse machines out there.

Sorry to rant but this new Government has me scared to death.
 
G

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^^^^ it's one way the government can rid the highways of older cars, yes ? having to replace engine after engine gets expensive and eventually they (we) give up :(

it's only going to get worse, you watch :(
 

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... I have even noticed that flat tappet B&S, TECUMSEH, KOHLER ETC. are not lasting as long now days. If you think auto engine parts are high $$. Try pricing small engine parts.
Lowering the ZDDP levels in most modern oils will be costly for the uninformed. Not only for their PRIDE & JOY but the everyday workhorse machines out there.

Sorry to rant but this new Government has me scared to death.
The flat tappet is the fastest wearing part because of the loading (psi) but rings are wearing exceptionally fast as well without ZDDP in the oil.

ZDDP was removed to prevent the manufactures from having to replace a cat before 100,000 miles (required by federal code) is up. If your motor dies it will be out of warranty and not their concern (if you buy an extended warranty it is an insurance policy not a warranty so once again they are not motivated to care).

Big Dave
 

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Mike cam break in is one of the most feared aspect of building engines for me. If it goes wrong it pretty much means you get build a motor all over again.

I removed my inner springs to reduce the pressure on the cam during break in. I used Chevron Delo 10-30 because of the ZDDP content and a bottle of the original GM EOS additive. Ran the motor for 20 minutes, then drained the oil and changed the filter checking for metal. Refilled with 5 qts of new Delo, added a full bottle of the Crane additve for cam break in and ran it another 30 minutes. After that I started it up a few times just to hear it run :D. I now feel comfortable it is ready for the inner springs and to be installed in the car. After 100 -150 miles I will again change the oil and filter but this time use one of the automotive racing/off road type oils with good levels of ZDDP.
 

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Discussion Starter · #34 ·
Well my cam is in my pan, two lobes were way round, "my bad" so since the motor only has 2500mi. on it should I replace the main and rod bearings along with the cam bearings. Do you think they were harmed much.
I think I'll do it anyway, why chance it.
Thanks
 

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finely shaved metal parts going through all yor oil pasages and anywhere there oil.

If it were me, complete disassembly and to the hot tank the block would go. Pistons and rods would see time in a varasol bath to ensure there is no fine particles of metal clinging to the pistons and rod and not hiding in the ring land grooves. The crank would also see the varasol tank. The heads would see the varasol tank. Oil pan will need a bath in the varasol tank too. As for the oil pump, they are generally inexspensive, it would see the garbage can along with the oil filter.

Basically you need to clean every party of the motor. You dont wanna just swap out bearing and put it back together because there are more than likely fine minute oil shavings everywhere.:thumbsup:
 

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I thought I knew how to clean an engine in preperation for assembly, i had all the long handled brushes, plenty of solvent....until I had a good friend that builds custom engines clean mine. He found lots of crud I missed. Using lots of brake clean and the brushes mounted in a cordless drill every passage was thoroughly cleaned until only clear liquid came out, this included the cylinder bores and the oil holes in the crank shaft. Next step was a soapy water bath, rinse and blow dry with compressed air. Like i said even though i thought I had it clean there was a lot of crud still in there.
 
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