Oil pump thread
11-27-2014, 11:38 AM
#31
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I would up the rod bolts to the ARP 2000's and stud the caps.of course this means the main line is gonna need honing,but then you could set the bearing clearance better.I'd personally check the crank,unless eagle got better,my journals were all over the place.pita to set up.but once done has been bullet proof for over 8yrs.
11-27-2014, 12:13 PM
#33
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iTrader: (1)
Mark, great info as usual. Question for you, or anyone with knowledge in this area, slightly off topic. But, what do you think of the components here in Icdedppl's shortblocks?
540ci
Mark IV bowtie block
Eagle H beams with 8740 bolts
Iron Main caps with standard bolts, non splayed
Eagle Crank 4.250
900HP 6000RPM roots blown engines.
My gut would want to go thru the bottom ends, and minimum go with better rod bolts, possibly main studs or billet caps. I personally more worried about that than the oil pressure. Is there a legit concern here?
540ci
Mark IV bowtie block
Eagle H beams with 8740 bolts
Iron Main caps with standard bolts, non splayed
Eagle Crank 4.250
900HP 6000RPM roots blown engines.
My gut would want to go thru the bottom ends, and minimum go with better rod bolts, possibly main studs or billet caps. I personally more worried about that than the oil pressure. Is there a legit concern here?
11-28-2014, 08:54 AM
#38
To expand on the technical side of this some more.... The jump from the 8740 (200K psi tensile) to ARP2000 (220K psi tensile) is only 10%, while L19 (260K tensile)((L19 are made of a very tempermental alloy. Most applications are suited just fine with ARP2000 rod bolts.)) is 30% more, but before people go claiming that the 8740 is "junk" they just need to compare it to a Grade 8 bolt at 150K tensile strength, 8740 is 33% stronger than a Grade 8 bolt! If we look at yield strengths the 8740 and ARP2000 are both right at 180K psi yield, or 50% more than a Grade 8 bolt.... and yeild is a much better figure to look at here.
The problem with the L19 bolts is a condition called "hydrogen embrittlement" which means it absorbs hydrogen easily and causes stress cracks, most likely cause is when the parts exposed to moisture... even that from your hands. It makes these bolts at PITA to deal with because you need to clean them well with solvent and use gloves with them and immediately oil them. Wiki on it http://en.wikipedia.org/wiki/Hydrogen_embrittlement
Now how about the difference... what do you need? Well you need to know the piston acceleration and the component mass, but to make it simple a 10% increase in mass or piston acceleration means you need 10% more clamping load.
So if you are looking at a 3.48" stroke SBC circle track motor with let's say a 400g piston turning 8500rpm, your at about 4600 piston g's.... (which I know is super safe on a 8740 Eagle Rod) Now compare that to a 406 with a dome piston that's 500g the piston g's need to be about 3700 which is about 7250rpm.... at that level you will basically see the same amount of stress on the rods/rod bolts.... say you put the L19 bolts in that rod, that should get you up to the same RPM level with a similar safety factor on the rod bolts.
The problem with the L19 bolts is a condition called "hydrogen embrittlement" which means it absorbs hydrogen easily and causes stress cracks, most likely cause is when the parts exposed to moisture... even that from your hands. It makes these bolts at PITA to deal with because you need to clean them well with solvent and use gloves with them and immediately oil them. Wiki on it http://en.wikipedia.org/wiki/Hydrogen_embrittlement
Now how about the difference... what do you need? Well you need to know the piston acceleration and the component mass, but to make it simple a 10% increase in mass or piston acceleration means you need 10% more clamping load.
So if you are looking at a 3.48" stroke SBC circle track motor with let's say a 400g piston turning 8500rpm, your at about 4600 piston g's.... (which I know is super safe on a 8740 Eagle Rod) Now compare that to a 406 with a dome piston that's 500g the piston g's need to be about 3700 which is about 7250rpm.... at that level you will basically see the same amount of stress on the rods/rod bolts.... say you put the L19 bolts in that rod, that should get you up to the same RPM level with a similar safety factor on the rod bolts.
My bottom end is fine for the horsepower I`m running.. any more and changes would have to be made, Im running what I got until something breaks.
At or below 6200 ish with a 4" stroke crank and a flat top, the 8740 bolt is fine. The 2000 is a better bolt, but not necessary in that application. I do not recommend the L19 for anything other than a race engine. -
Borgie; L19?
Last edited by ICDEDPPL; 11-28-2014 at 08:58 AM.
11-28-2014, 09:33 AM
#39
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iTrader: (3)
• ARP 8740 chrome moly rod bolt - a strong affordable rod bolt, but it has only a moderate fatigue life, which makes the ARP 2000 rod bolt which is in the same general price range, a much better choice since it has twice the fatigue life.
• ARP 2000 rod bolt - considering how good its strength and fatigue life are, this rod bolt is an excellent choice for most Hotrods, Street/Strip cars, and Sportsman Drag cars.
• ARP L19 rod bolt - the strength and fatigue life increases this bolt provides over the ARP 2000 are not significant enough to overcome the concerns the L19 has with hydrogen embrittlement, stress corrosion, and the fact that it CANNOT be exposed to any moisture, including sweat and/or condensation. Don’t forget that every engine forms condensation inside, at every cold start-up. Plus, oil rises to the top of, and floats on water because of density differences, which can leave portions of the rod bolts exposed to water even after the engine is built. Therefore, it is best to avoid the L19 rod bolt altogether, especially since the ARP 2000 rod bolt already provides way more than enough strength and fatigue life than is typically required by most Hotrods, Street/Strip cars, and Sportsman Drag cars. So, there simply is no good reason to select the ARP L19 rod bolt. If you are currently running L19 bolts, I’d suggest you consider replacing them with different bolts the next time you have the motor apart.
• ARP Custom Age 625+ rod bolt - a very pricey bolt, but with its excellent strength and its impressive fatigue life, this bolt is one of the very best rod bolts on the market.
• ARP 3.5 rod bolt - this bolt has excellent strength, but its staggering cost is 43% HIGHER than the 625+ bolt, yet the 625+ bolt is superior to the 3.5 bolt in virtually every way. So, there is no good reason to select the 3.5 bolt either.
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CONCLUSION and RECOMMENDATION
Of the 5 rod bolts above:
• The ARP 2000 rod bolt is an excellent value, considering how good its strength and fatigue life are. And it should be considered the rod bolt of choice for most Hotrods, Street/Strip cars, and Sportsman Drag cars, no matter how much HP they make. And this is why you most often see quality aftermarket rods come with these bolts.
• ARP Custom Age 625+ rod bolt has a price that is not for the faint of wallet, but it should be considered the rod bolt of choice for very high revving engines, road race engines, and endurance engines, which require the utmost in rod bolt strength and/or fatigue life.
11-28-2014, 09:45 AM
#40
Back to my oil pump, it looks like its already Melling select 10778 .
http://www.jegs.com/i/Melling/689/10...oductId=751586
http://www.jegs.com/i/Melling/689/10...oductId=751586
