704ci Motor Help
07-09-2014 | 05:27 PM
#31
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From: bel air, md
07-09-2014 | 05:31 PM
#32
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From: bel air, md
Hey guys, I found best with my blown 600+" motor is the tall baffles like Teague and the magic trick get some fuel cell foam. Pull the cap off the baffle and fit some fuel cell foam in the top and put cover back on!!
This has 99.999999999% fixed all my oil issues out the breathers. Before I did the foam after every time out i was back there wiping up damn oil.That and make sure you don't have oil coming out the oil dip stick. It would be a good idea to get a long spark plug boot over the dip stick to seal that up. Good luck!!
Skydog http://www.amazon.com/Racing-20217-F...fuel+cell+foam
This has 99.999999999% fixed all my oil issues out the breathers. Before I did the foam after every time out i was back there wiping up damn oil.That and make sure you don't have oil coming out the oil dip stick. It would be a good idea to get a long spark plug boot over the dip stick to seal that up. Good luck!!Skydog http://www.amazon.com/Racing-20217-F...fuel+cell+foam
07-09-2014 | 05:47 PM
#33
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From: frankenmuth michigan
1. tons of stroke whipping air and oil around in crankcase
2. Unless the block is super ultra tall deck the piston pins are prob way up in the pistons with short skirts to clear that mongo stroke which causes the piston to rock in bore easier and compromises ring seal
3. as mentioned, the volume of crankcase is no kore than stock vs pumping action of pistons with a long ass stroke. I have a 2 cyl OMC air cooled engine in something that has tiny crankcase but large bore pistons and stroke, if you open the oil fill while its running it pumps air out of crankcase like a air compressor and whips oil around ferosiously
2. Unless the block is super ultra tall deck the piston pins are prob way up in the pistons with short skirts to clear that mongo stroke which causes the piston to rock in bore easier and compromises ring seal
3. as mentioned, the volume of crankcase is no kore than stock vs pumping action of pistons with a long ass stroke. I have a 2 cyl OMC air cooled engine in something that has tiny crankcase but large bore pistons and stroke, if you open the oil fill while its running it pumps air out of crankcase like a air compressor and whips oil around ferosiously
07-09-2014 | 05:57 PM
#34
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From: frankenmuth michigan
I would also tend to believe there is some ring seal issue, did the original builder "freshen" motors or test run them and say they are good to go? I would think about a leakdown test if we are talking alot of blow by. Everyone crys about them not working but I have had excellent results with my blown 540 using zero gap rings, less than 5% leakdown after dynoing and until it hits 80-120 hard hours very little blow by, I do also run tall breathers on front of valve covers, Smitty
07-09-2014 | 06:07 PM
#35
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From: bel air, md
1. tons of stroke whipping air and oil around in crankcase
2. Unless the block is super ultra tall deck the piston pins are prob way up in the pistons with short skirts to clear that mongo stroke which causes the piston to rock in bore easier and compromises ring seal
3. as mentioned, the volume of crankcase is no kore than stock vs pumping action of pistons with a long ass stroke. I have a 2 cyl OMC air cooled engine in something that has tiny crankcase but large bore pistons and stroke, if you open the oil fill while its running it pumps air out of crankcase like a air compressor and whips oil around ferosiously
2. Unless the block is super ultra tall deck the piston pins are prob way up in the pistons with short skirts to clear that mongo stroke which causes the piston to rock in bore easier and compromises ring seal
3. as mentioned, the volume of crankcase is no kore than stock vs pumping action of pistons with a long ass stroke. I have a 2 cyl OMC air cooled engine in something that has tiny crankcase but large bore pistons and stroke, if you open the oil fill while its running it pumps air out of crankcase like a air compressor and whips oil around ferosiously
I understand what you are saying and it makes sense. But I've been around these types of motors and have seen the opposite. I had an 865 in front of me running with the valve cover off and didnt have oil all over me. Granted it wasn't wide open spinning 9000 rpm but I noticed no signs of excess windage. Honestly, what I've noticed with these types of motors is that it seems like they have less windage. I mean the crank and rods practically hit the block. Oil gets scraped off the crank and rods by the block. I had a 496 that puked way more oil than the 598 or 632 I've had. Same valve covers and breathers on all 3 motors. And the 496 spun 1000 less rpm...
07-09-2014 | 07:01 PM
#36
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From: ILL
07-09-2014 | 07:10 PM
#37
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From: bel air, md
No I'm poor. Can't afford cool stuff like a blower or dry sump. No, actually I was gonna go with a dry sump but engine builder talked me out of it said it was a waist of money on a motor like that.
07-09-2014 | 07:16 PM
#38
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From: On A Dirt Floor
07-09-2014 | 07:24 PM
#39
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From: bel air, md
Yeah I know what he was laying down. The point I was trying to get across is no matter how big the motor is it should not have so much windage that it pushes oil out the breathers. If the breathers are baffled and oil is being pushed out there is probably an internal problem. As Arcticfriends said I think a leakdown may be in order.
