Scat Rods Power Level
I skipped Gen 3 rods, but Gen 4 rods have seen hell! Honestly on the low side of 1000hp I don't know how anyone messes them up.
In theory an offshore lightweight rod has potential to be worse than stock. A few brands did not recommend their lightweight stuff be used for what I was intending for multiple reasons, even though a stock rod already survived it.
In theory an offshore lightweight rod has potential to be worse than stock. A few brands did not recommend their lightweight stuff be used for what I was intending for multiple reasons, even though a stock rod already survived it.
Small block chevy guys that are used to replacing every single OEM part other than the block (and sometimes the block) to make 400-500 HP.
I frequent corvetteforums in the C4 sections because I technically own one. Some of the stuff I see there is absolutely absurd.
They have no problem spending $8-10k on a 425 hp 383 and absolutely refuse to believe an LS engine can make more than that without forged everything.
They argue about absolutely everything that seems derogatory to their cars in any way, refuse to believe the C4 isn't the best car in existence, and scoff at any logical comparison to another car you try to give them.
Some of those guys have their head so far up Nostalgia's a** that they refuse to believe anything that wasn't common knowledge in 1988.
I frequent corvetteforums in the C4 sections because I technically own one. Some of the stuff I see there is absolutely absurd.
They have no problem spending $8-10k on a 425 hp 383 and absolutely refuse to believe an LS engine can make more than that without forged everything.
They argue about absolutely everything that seems derogatory to their cars in any way, refuse to believe the C4 isn't the best car in existence, and scoff at any logical comparison to another car you try to give them.
Some of those guys have their head so far up Nostalgia's a** that they refuse to believe anything that wasn't common knowledge in 1988.
If you want to make them cry, point out the C5Z06 will slaughter the C4ZR1
C3 crowd is very similar with many arguments that RamHorm manifolds are as good or better than 1 3/4 primary long tube headers.
Last edited by 99 Black Bird T/A; Jan 6, 2022 at 03:39 PM.
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only one motor destroyed, the one with Gen4 rods. You’re entitled to your own wrong opinion. Why are all the good pistons made with .927 pins? Because the manufactures wants you to re use you’re Presto Log Gen4 rods? You may argue all you want, lighter forged rod with good fasteners is just better, not saying you can’t use a Gen4 as in my original post on this thread, they are used in high hp applications, just not by me. Why does GMPP supply LSX motors without Gen4 if they’re so good? ( they use Scat Ibeam) Why do most all performance LS engine providers use aftermarket rods? Because Gen4 rods are so good? Have you ever used a dial bore gauge on a set of used Gen4 rods? They’re not very round, you can use them in your builds. As for your aluminum rod rant, those things have a very short, short life span, require lots of clearance in the crankcase to even fit because of they’re bulk size, pistons need to down the hole a lot.
The big end being more round has more to do with the life of the rod and not what it is made from or who made it. Put 250k miles on a set of forged rods and tell me they are still round.
Without metallurgy data, you can't directly argue that a lightweight forged rod with good fasteners is better.
If you had the metallurgy data, you wouldn't be so quick to make bold claims, either. Powered metal rods are technically "forged" in the same manner that aftermarket rods are.
Most powdered metal rods rank higher on the hardness scale than 4340 forged rods.
GKN, the driving force behind most current forged powdered metal technology even claims that powdered forgings are much stronger than typical forged steel.
https://www.gknpm.com/en/our-busines...als/forged-pm/
Most newer PM rods are made of ASTM 4260, which has both a higher yield strength and ultimate tensile strength than 4340.
Knowing that, you can't honestly say that 4340 rods forged in china are definitely free of forging imperfections and are 100% the material they are supposed to be.
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Had a acquaintance that was affiliated with SCAT, they are totally OCD about their materials ,,
they follow the metal all the way from the initial recycle through the process, foundering forging till they put them on the boat.
They had some issues back when they were forced to move the billet/forging processes offshore..
They learned their lesson and now NOTHING gets without supervision by their people.
they follow the metal all the way from the initial recycle through the process, foundering forging till they put them on the boat.
They had some issues back when they were forced to move the billet/forging processes offshore..
They learned their lesson and now NOTHING gets without supervision by their people.
only one motor destroyed, the one with Gen4 rods. You’re entitled to your own wrong opinion. Why are all the good pistons made with .927 pins? Because the manufactures wants you to re use you’re Presto Log Gen4 rods? You may argue all you want, lighter forged rod with good fasteners is just better, not saying you can’t use a Gen4 as in my original post on this thread, they are used in high hp applications, just not by me. Why does GMPP supply LSX motors without Gen4 if they’re so good? ( they use Scat Ibeam) Why do most all performance LS engine providers use aftermarket rods? Because Gen4 rods are so good? Have you ever used a dial bore gauge on a set of used Gen4 rods? They’re not very round, you can use them in your builds. As for your aluminum rod rant, those things have a very short, short life span, require lots of clearance in the crankcase to even fit because of they’re bulk size, pistons need to down the hole a lot.
It sounds like you don't know why .927 pins are the standard. It has nothing to do with the OEM LS rods and that was never even considered a factor by anyone.
The big end being more round has more to do with the life of the rod and not what it is made from or who made it. Put 250k miles on a set of forged rods and tell me they are still round.
Without metallurgy data, you can't directly argue that a lightweight forged rod with good fasteners is better.
If you had the metallurgy data, you wouldn't be so quick to make bold claims, either. Powered metal rods are technically "forged" in the same manner that aftermarket rods are.
Most powdered metal rods rank higher on the hardness scale than 4340 forged rods.
GKN, the driving force behind most current forged powdered metal technology even claims that powdered forgings are much stronger than typical forged steel.
https://www.gknpm.com/en/our-busines...als/forged-pm/
Most newer PM rods are made of ASTM 4260, which has both a higher yield strength and ultimate tensile strength than 4340.
Knowing that, you can't honestly say that 4340 rods forged in china are definitely free of forging imperfections and are 100% the material they are supposed to be.
The big end being more round has more to do with the life of the rod and not what it is made from or who made it. Put 250k miles on a set of forged rods and tell me they are still round.
Without metallurgy data, you can't directly argue that a lightweight forged rod with good fasteners is better.
If you had the metallurgy data, you wouldn't be so quick to make bold claims, either. Powered metal rods are technically "forged" in the same manner that aftermarket rods are.
Most powdered metal rods rank higher on the hardness scale than 4340 forged rods.
GKN, the driving force behind most current forged powdered metal technology even claims that powdered forgings are much stronger than typical forged steel.
https://www.gknpm.com/en/our-busines...als/forged-pm/
Most newer PM rods are made of ASTM 4260, which has both a higher yield strength and ultimate tensile strength than 4340.
Knowing that, you can't honestly say that 4340 rods forged in china are definitely free of forging imperfections and are 100% the material they are supposed to be.
Had a acquaintance that was affiliated with SCAT, they are totally OCD about their materials ,,
they follow the metal all the way from the initial recycle through the process, foundering forging till they put them on the boat.
They had some issues back when they were forced to move the billet/forging processes offshore..
They learned their lesson and now NOTHING gets without supervision by their people.
they follow the metal all the way from the initial recycle through the process, foundering forging till they put them on the boat.
They had some issues back when they were forced to move the billet/forging processes offshore..
They learned their lesson and now NOTHING gets without supervision by their people.
It sounds like you don't know why .927 pins are the standard. It has nothing to do with the OEM LS rods and that was never even considered a factor by anyone.
The big end being more round has more to do with the life of the rod and not what it is made from or who made it. Put 250k miles on a set of forged rods and tell me they are still round.
Without metallurgy data, you can't directly argue that a lightweight forged rod with good fasteners is better.
If you had the metallurgy data, you wouldn't be so quick to make bold claims, either. Powered metal rods are technically "forged" in the same manner that aftermarket rods are.
Most powdered metal rods rank higher on the hardness scale than 4340 forged rods.
GKN, the driving force behind most current forged powdered metal technology even claims that powdered forgings are much stronger than typical forged steel.
https://www.gknpm.com/en/our-busines...als/forged-pm/
Most newer PM rods are made of ASTM 4260, which has both a higher yield strength and ultimate tensile strength than 4340.
Knowing that, you can't honestly say that 4340 rods forged in china are definitely free of forging imperfections and are 100% the material they are supposed to be.
The big end being more round has more to do with the life of the rod and not what it is made from or who made it. Put 250k miles on a set of forged rods and tell me they are still round.
Without metallurgy data, you can't directly argue that a lightweight forged rod with good fasteners is better.
If you had the metallurgy data, you wouldn't be so quick to make bold claims, either. Powered metal rods are technically "forged" in the same manner that aftermarket rods are.
Most powdered metal rods rank higher on the hardness scale than 4340 forged rods.
GKN, the driving force behind most current forged powdered metal technology even claims that powdered forgings are much stronger than typical forged steel.
https://www.gknpm.com/en/our-busines...als/forged-pm/
Most newer PM rods are made of ASTM 4260, which has both a higher yield strength and ultimate tensile strength than 4340.
Knowing that, you can't honestly say that 4340 rods forged in china are definitely free of forging imperfections and are 100% the material they are supposed to be.
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The early Ford V10's that would lose the bore in 60K are another example..
You'd think American business would notice, but even today I see manufacturers getting burned by quality control in the offshore countries, they keep
making the mistake that they can just send a design and don't have to be exactly detailed in specs...
Covid has not helped a bit either..
Speaking of kids, even the gen4 engine my kid assembled didn't blow up. Careful, those heavy rods could fly out at any time!!
It’s probably worth noting that rod bolts aren’t stressed as much from RPM in a boosted application. The extra pressure in the chamber at TDC during the exhaust phase acts like a cushion, so tensile loads are considerably reduced. Corky Bell wrote about this in his book.
Last edited by KCS; Jan 7, 2022 at 12:08 PM.
The push offshore to the Far East for forging and casting was not pain free for any of the manufacturers,
The early Ford V10's that would lose the bore in 60K are another example..
You'd think American business would notice, but even today I see manufacturers getting burned by quality control in the offshore countries, they keep
making the mistake that they can just send a design and don't have to be exactly detailed in specs...
Covid has not helped a bit either..
The early Ford V10's that would lose the bore in 60K are another example..
You'd think American business would notice, but even today I see manufacturers getting burned by quality control in the offshore countries, they keep
making the mistake that they can just send a design and don't have to be exactly detailed in specs...
Covid has not helped a bit either..
FWIW, I’ve seen the Scat I Beams hold up to 900whp. Out of the box, I think the pin bores are tight for any serious performance engine, but that’s a cheap fix that should be checked on any build anyways. I think they’re a great option to help take weight out of the rotating assembly and open up options for pistons.
Not sure I follow. If the chamber still has pressure with the piston at BDC then it would take more crank force to lift the piston back up in the cylinder because its got to push against the exhaust pressure built up in the chamber. I would assume that exhaust backpressure would make exacerbate this as well. For a given RPM, the duration would be the same regardless of NA or boosted, so the stress isnt spread out of any longer duration. I read Corky's book, but it was ages ago. Could you explain?
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Stress on the rod bolts is typically highest at the end of the exhaust stroke and beginning of the intake stroke due to inertia of the piston/rod coming to a stop and then being yanked back downward. In a boosted application, additional exhaust pressure provides a cushion at the top of TDC to help work in the opposite direction of inertia, along with the additional intake pressure coming in during overlap as opposed to the vacuum that would normally try to pull the piston upward during the intake downstroke.
Basically, boost reduces the stress on the rod bolts during the most crucial moments.
Basically, boost reduces the stress on the rod bolts during the most crucial moments.
Not sure I follow. If the chamber still has pressure with the piston at BDC then it would take more crank force to lift the piston back up in the cylinder because its got to push against the exhaust pressure built up in the chamber. I would assume that exhaust backpressure would make exacerbate this as well. For a given RPM, the duration would be the same regardless of NA or boosted, so the stress isnt spread out of any longer duration. I read Corky's book, but it was ages ago. Could you explain?
up to? that's not great for a forged aftermarket product. A ton of stock rods have handled that and more, some LS2 and LS3's have been making 900hp for many years, some 10+. For instance one of my old SBE L76's won't die, its been beat on as a big cam NA car spun over 7500, then with a grossly overspun maggie on top of it, then swapped to twin turbos, then a big single turbo without a care for max boost level, then a procharger spun thousands of RPM past what they recommend, the engine just takes all of it hasn't missed a beat in 13 years. Its almost annoying I also have an SBE LS2 that's been boosted since 2007, after 12 years of turbo abuse its finally nipped one ring land in 2019 seeing almost 30 PSI and didnt even damage the cylinder. I get people have bad luck sometimes, but the Gen 4 SBE stuff really seems incredibly strong for the average person. As mentioned before using aftermarket parts for under 1000hp is often more trouble than its worth.
Curious how long they would hold it, seems even stock rods will hold 1400'ish for a short time.
Cesar routinely posts high hp SBE builds as well. He also says it's not worth corrupting a SBE with aftermarket parts for less than 1000hp.
I also have an SBE LS2 that's been boosted since 2007, after 12 years of turbo abuse its finally nipped one ring land in 2019 seeing almost 30 PSI and didnt even damage the cylinder. I get people have bad luck sometimes, but the Gen 4 SBE stuff really seems incredibly strong for the average person. As mentioned before using aftermarket parts for under 1000hp is often more trouble than its worth.
Cesar routinely posts high hp SBE builds as well. He also says it's not worth corrupting a SBE with aftermarket parts for less than 1000hp.
up to? that's not great for a forged aftermarket product. A ton of stock rods have handled that and more, some LS2 and LS3's have been making 900hp for many years, some 10+. For instance one of my old SBE L76's won't die, its been beat on as a big cam NA car spun over 7500, then with a grossly overspun maggie on top of it, then swapped to twin turbos, then a big single turbo without a care for max boost level, then a procharger spun thousands of RPM past what they recommend, the engine just takes all of it hasn't missed a beat in 13 years. Its almost annoying I also have an SBE LS2 that's been boosted since 2007, after 12 years of turbo abuse its finally nipped one ring land in 2019 seeing almost 30 PSI and didnt even damage the cylinder. I get people have bad luck sometimes, but the Gen 4 SBE stuff really seems incredibly strong for the average person. As mentioned before using aftermarket parts for under 1000hp is often more trouble than its worth.
I also have an SBE LS2 that's been boosted since 2007, after 12 years of turbo abuse its finally nipped one ring land in 2019 seeing almost 30 PSI and didnt even damage the cylinder. I get people have bad luck sometimes, but the Gen 4 SBE stuff really seems incredibly strong for the average person. As mentioned before using aftermarket parts for under 1000hp is often more trouble than its worth.I don’t think either is objectively better, you can use whichever you like. The Gen IV rod is robust and cheaper since they’re 20 years old and mass produced, but the Scats are light, have good ARP bolts, and open up a lot of options for piston choices.