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oil pressure problems (DONT USE HIGH VOLUME) see pg 2 for rebuild beginnings

Correct, my current set up I should have ran 87 octane. It was ran crappy on 87, but that was probaly because i had too big of a carb on it.

With the 10.3 and 64cc Al heads I would need the 93.
 
What I was saying is that 10.3 with what you have planned, should run on 87. This is why old heads (like camel humps) suck, and there is no way around it. :)
 
Your thread posts not too use a high volume oil pump. Were you jumping to conclusions or am I missing something? You don't sound like an engine builder so why the bad rap for the high volume pump? Just wondering?
 
4-play said:
Your thread posts not too use a high volume oil pump. Were you jumping to conclusions or am I missing something? You don't sound like an engine builder so why the bad rap for the high volume pump? Just wondering?
Click to expand...

Read post 4 page one by:bow: resident high performace engine builder.:bow:
 
4-play said:
Your thread posts not too use a high volume oil pump. Were you jumping to conclusions or am I missing something? You don't sound like an engine builder so why the bad rap for the high volume pump? Just wondering?
Click to expand...

For a stock or mostly stock engine the stock oil pump is fine. Even with a stock pump a sbc easily oils to an extreme on top. Adding pressure or volume just adds load to the engine you will probably never need.

And another question for the OP, you said you changed the pan. Where is the pickup sitting in the pan, how far from the bottom of the pan? And how is it sealed to the pump so it doesn't suck air?
 
4-play said:
Your thread posts not too use a high volume oil pump. Were you jumping to conclusions or am I missing something? You don't sound like an engine builder so why the bad rap for the high volume pump? Just wondering?
Click to expand...


I'm not, from what 4x4high said, my machinist, and my boss has all stated it appears that at one point the clearances were not 100%correct, and the High volume pump pushed too much oil. Starving some places more than others.

The oil pan is I believe a Summit brand? I bought it at a local swap meet. When I had the stock pan off, and the new one not on yet. I measured the depth in both pans, I believe the measurements were different by 1/4" I could be wrong though. AT that point in time that seemed acceptable to me, So I put it back together.

The sump pickup is just stuck into the pump, It feels tight, its hard to rotate in the pump.

I was always taught that anything above 10.0 on cast heads would cause detonation even with 93, Now that I think about it, it makes sense what your saying. The aluminum heads run cooler, which is why you can get away with higher ratios. And like your saying 87 octane possibly.
 
The only time I have heard that high volume oil pumps cause a problem is when you run high rpm's for an extended time. Even so, if you work your heads and block I don't see drain back as a problem. I would bet my next paycheck that I can run at 6500rpm for 5 min straight with no problems. I run a Melling 555. If you have bearing clearance issues how did the oil pump lead to failure? It would have failed with any pump IMHO. There is also alot more to compression ratio than just heads and the static compression ratio they have. Camshaft selection can make a huge difference in the ratio that you run. A cam with a long overlap will allow you to run more compression. I run approx. 11 to 1 with iron heads. I know I'm the new guy, but I don't see the problem with the HVOP. If I'm wrong, explain it to me and I will be the first to say I was wrong.
I enjoy learning and when your wrong it really sinks in. Thanks.
 
I've owned three small blocks, including one with 13 to 1 compression, etc and have always used the stock pump. They generally run 40lbs at an idle. While I freely admit to being an old fart, I've always heard that too much OP in a small block tends to wash the oil off the bearings. Bottom line: I've never felt a need to have a high output pump.
 
My understanding is that the SBC oiling system is such a great design to begin with that the high volume oil pump just costs power with no gain.

I am by no means an engine builder, If I was I would have a running engine instead of a pile of parts in my basement. this is just my understanding of the topic.
 
Non cross drilled cranks only oil the rods every 180° of crankshaft rotation.
as the oil hole in the main journal rotates onto the half of the bearing without the groove,, it covers the oil pressure supplied to the main journal.

Cross drilled cranks have oil holes 180° from each other on the crank journal
as the name implies,,the journal is cross drilled from one side to the other.
That way no matter what position the crank is in ( in it's rotation ) one of the oil holes in the main journal will always be supplying oil to the connecting rods.

You can also use a 360° grooved main bearing set, but I wouldn't recomend it.
 
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Okay, that makes sense. Now that I actually think about it, I do remember seen two holes in the mains.

I just found my Eagle paperwork, and that IS the crank that I have.
 
Any BBC or SBC crank can be crossdrilled by a decent crank grinder.
It's cheap insurance for your rod bearings.

I would be careful about doing this mod on a cast crank if you plan to push the engine hard. but then again,,I have done them with no problems ever.

Then again, if your going to run it hard,,stepping up to a steel crank is your best bet..
 
Let me know if I'm missing something...but according to Summit, my crank is already crossed drilled. So I should be Ok.
 
Let me know if I'm missing something...but according to Summit, my crank is already crossed drilled. So I should be Ok.
Click to expand...

Your crank is good to go....


CLEAN ALL OF YOUR OIL PASSAGES BEFORE YOU INSTALL THE NEW BEARINGS AND CRANK !!!!

I can't stress this enough....


If you don't own / use micrometers ....Plastigage is your friend...
get to know it and use it on EVERY main and rod bearing..torque it to spec and then take the cap back off and measure the squish of the plastigage...yes it takes time. But look at all the time you wasted up till this point on the original build.
 
yeah... Trust me..things will be checked three times this time. :D

Plus the machicists son is going to help me put it all together this time.

The block is being hot tanked/washed, and is geting new cam bearings as well.
 
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