What is the fastest you can spin the stock bottom end???
09-02-2010, 08:47 PM
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What is the fastest you can spin the stock bottom end??? Pretty much what the title says. I want to put a bigger cam, intake, and keep the stock heads but do some head work to them. So really what it boils down to is how many rpm's can the stock bottom end handle?
09-02-2010, 08:57 PM
#2
Some guys spin them to 7200 but to be safe I would say no more then 7000 and I wouldnt do it evey stop light. At the track every now and then you'll be fine I would drop the oil pan and put some arp bolts for peace of mind. But I personaly spin my stock bottom end with 86K + between 6800-6900 rev. limiter set at 7000K. Hope this helps
09-02-2010, 09:09 PM
#3
Depends on your valvetrain setup but this should help:
The limit is dictated by the equation (RPM x Stroke)/6. If the number you get is over 4600, you need a forged crank. If you get over 5500, you need a shorter stroke or less RPM.
If you want to just spin the crap out of your engine and you still have the stock springs, pushrods, lifters, etc you aren't gonna be too happy with the results
The limit is dictated by the equation (RPM x Stroke)/6. If the number you get is over 4600, you need a forged crank. If you get over 5500, you need a shorter stroke or less RPM.
If you want to just spin the crap out of your engine and you still have the stock springs, pushrods, lifters, etc you aren't gonna be too happy with the results
09-02-2010, 10:01 PM
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Depends on your valvetrain setup but this should help:
The limit is dictated by the equation (RPM x Stroke)/6. If the number you get is over 4600, you need a forged crank. If you get over 5500, you need a shorter stroke or less RPM.
If you want to just spin the crap out of your engine and you still have the stock springs, pushrods, lifters, etc you aren't gonna be too happy with the results
The limit is dictated by the equation (RPM x Stroke)/6. If the number you get is over 4600, you need a forged crank. If you get over 5500, you need a shorter stroke or less RPM.
If you want to just spin the crap out of your engine and you still have the stock springs, pushrods, lifters, etc you aren't gonna be too happy with the results
09-02-2010, 10:19 PM
#5
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Depends on your valvetrain setup but this should help:
The limit is dictated by the equation (RPM x Stroke)/6. If the number you get is over 4600, you need a forged crank. If you get over 5500, you need a shorter stroke or less RPM.
If you want to just spin the crap out of your engine and you still have the stock springs, pushrods, lifters, etc you aren't gonna be too happy with the results
The limit is dictated by the equation (RPM x Stroke)/6. If the number you get is over 4600, you need a forged crank. If you get over 5500, you need a shorter stroke or less RPM.
If you want to just spin the crap out of your engine and you still have the stock springs, pushrods, lifters, etc you aren't gonna be too happy with the results
Stock rod bolts ls1, go 6600-6700, if its making power up there.
Arp rod bolts, go 7000-7200.. as long as there is power up there.
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09-02-2010, 10:43 PM
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09-02-2010, 10:56 PM
#8
Aren't genIII engine nodular cranks? Also, max piston speed vs piston type usually determines max rpm the bottom end is capable of surviving regularly. valvetrain determines the actual limits of power.
09-02-2010, 11:18 PM
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That is right it is all about max piston speed and yes these engines have a very good bottom end , i have a 4.8 with a 3.270in stroke compared to a 3.622in LS1 and i put the shift points to 6400 , i have upgraded my springs and pushrods with cam and i am going to change my rod bolts so i can raise my shift points to 6900 , all this sits below a magnuson SC with a very special intercooler
09-03-2010, 12:29 AM
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This thread is full of garbage. You can spin a stock bottem end to the moon, just don't expect it to last. Valve spring and pushrods should top your list. A lot of people say 98 rod bolts are junk, some say they take them to 7200rpm daily. 99+ are suppose to be a lot better, maybe. If you want peice of mind throw some Katechs in, **** ARP. They are a nice rod bolt, if you want to take the rods out and have them honed/put back into round. Yet again some people don't and get away with it. Wanna take that chance? Bottem line, a good valve spring, pushrod, and Katech rod bolts (designed to not have to have the rod put back into round) and you can spin it higher then your plastic intake is ever going to flow.
09-03-2010, 10:50 AM
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Out of curiosity why are you needing so many rpm's? There is a lot that goes into making a motor spin high rpm's as the rotational mass of something as large as a V8 spinning that high is massive. Are you building a road race engine or just want something that spins high for fun? There are plenty of ways of making power without having to spin so many rpm's as you stock shortblock is not going to stay together long if you start reving the hell out of it, especially without a proper valvetrain and cam.
09-03-2010, 02:46 PM
#15
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This thread is full of garbage. You can spin a stock bottem end to the moon, just don't expect it to last. Valve spring and pushrods should top your list. A lot of people say 98 rod bolts are junk, some say they take them to 7200rpm daily. 99+ are suppose to be a lot better, maybe. If you want peice of mind throw some Katechs in, **** ARP. They are a nice rod bolt, if you want to take the rods out and have them honed/put back into round. Yet again some people don't and get away with it. Wanna take that chance? Bottem line, a good valve spring, pushrod, and Katech rod bolts (designed to not have to have the rod put back into round) and you can spin it higher then your plastic intake is ever going to flow.
I just see more internet myths posted in your little "truth from god" speech.
If you dont belive you need to resize on a Katech bolt your smoking some good **** too. ARP or Katech.. proper way is to resize. Does anyone do it? Rarely.
Spin it to the moon? Go ahead tell me how many times your stock rod bolted ls1 bottom makes it to 8k.
09-03-2010, 04:58 PM
#17
you dont resize bolts. you resize the rod because of the new bolts making the rod out of round. NYSBADMK8 is just saying no matter what bolt is used (katech, or ARP) the rod will need to be resized because thats the propper way of doing a rod bolt swap.
09-03-2010, 05:26 PM
#20
Chrs your car is a freak
Whoever said it's about the crank NOOOOO it's about the OEM rodbolts. They stretch long before the crank is anywhere close to it's limits resulting in a spun bearing
The OEM crank is damn good and can hold 700+ fwhp pretty easy
To stay safe the 98-00 limit is usually around 6500. Sure alot of people spin more and get away with it but many don't.
The 01-02's can usually safely do 6800 due to the upgraded OEM rodbolts.
Another variable to the equation is how often and long are you there.....
Whoever said it's about the crank NOOOOO it's about the OEM rodbolts. They stretch long before the crank is anywhere close to it's limits resulting in a spun bearing
The OEM crank is damn good and can hold 700+ fwhp pretty easy To stay safe the 98-00 limit is usually around 6500. Sure alot of people spin more and get away with it but many don't.
The 01-02's can usually safely do 6800 due to the upgraded OEM rodbolts.
Another variable to the equation is how often and long are you there.....