LS2/3 con rods...how good?
Thread Starter
Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
LS2/3 con rods...how good?
I know any time anyone builds or rebuilds an LS2/3 short block, they ALWAYS do forged pistons and rods with the stock crank (unless shooting for 900+ and then the crank gets forged). GM uses stock LS3 con rods in their made for boost LSX376. They must know a little something about what they're doing. Aren't a huge percentage of the failures with f/i related to the pistons, lean AFR's, and too much timing? Or just the weak assed pistons just giving up after many high power cycles. Do the stock rods ever **** the bed without the piston on top of them failing first?
I'm about to put a short block together that won't see north of 700 rwhp. Are forged rods a waste at this level? I understand the "cheap insurance" arguement, but forged rods ain't necessarily cheap. I'd rather use the cash somewhere else. I'm of the opinion that if you buy all the cheap insurance available, you're going to "insure" that you're going to have an expensive short block. Overbuilt is over spent if you don't need the super parts. Your thoughts appeciated
I'm about to put a short block together that won't see north of 700 rwhp. Are forged rods a waste at this level? I understand the "cheap insurance" arguement, but forged rods ain't necessarily cheap. I'd rather use the cash somewhere else. I'm of the opinion that if you buy all the cheap insurance available, you're going to "insure" that you're going to have an expensive short block. Overbuilt is over spent if you don't need the super parts. Your thoughts appeciated
Le Mans Master
Joined: Apr 2011
Posts: 7,821
Likes: 412
From: Montreal
St. Jude Donor '13
I would think the stock rods would be good for 700 assuming its not going to be a high rpm build. If keeping them I would consider getting them set up with some arp rod bolts.
My LS2 has gone for a while now on the stock short block with 615 rwhp and never had an issue.
That said, I am going with caillies ultra billet rods in my build, just for insurance.
My LS2 has gone for a while now on the stock short block with 615 rwhp and never had an issue.
That said, I am going with caillies ultra billet rods in my build, just for insurance.
Thread Starter
Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
I would think the stock rods would be good for 700 assuming its not going to be a high rpm build. If keeping them I would consider getting them set up with some arp rod bolts.
My LS2 has gone for a while now on the stock short block with 615 rwhp and never had an issue.
That said, I am going with caillies ultra billet rods in my build, just for insurance.
My LS2 has gone for a while now on the stock short block with 615 rwhp and never had an issue.
That said, I am going with caillies ultra billet rods in my build, just for insurance.
Drifting
Joined: Feb 2006
Posts: 1,585
Likes: 15
From: New Hartford IA
The biggest issue I see is using a stock rod with a better bolt is the chance it will need resizing on the big end. I know some say you can just run them, but it's not the right way to do things. For close to the same money you can get Scat I beams with 7/16th standard arp bolts. Some guys have really pushed these rods and you can get them in 6.125/.927 so you can use more common aftermarket pistons.
Safety Car
Joined: Dec 2009
Posts: 4,754
Likes: 303
yea, and I think the LSX376 pistons are no longer sold seperately. I tried to go this route w/ my build, but could only find 4 in the entire US. They were the only pistons designed to fit the stock rods w/o modification I think.
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Thread Starter
Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
The biggest issue I see is using a stock rod with a better bolt is the chance it will need resizing on the big end. I know some say you can just run them, but it's not the right way to do things. For close to the same money you can get Scat I beams with 7/16th standard arp bolts. Some guys have really pushed these rods and you can get them in 6.125/.927 so you can use more common aftermarket pistons.
Former Vendor
Joined: May 2005
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From: Valencia Ca
Drifting
Joined: Feb 2006
Posts: 1,585
Likes: 15
From: New Hartford IA
http://store.hkracingengines.com/pro...products_id=62
Just one place to buy them. I'd use these all day over stock, but yes there are better rods out there. I'd say they are a bang for the buck champ
Just one place to buy them. I'd use these all day over stock, but yes there are better rods out there. I'd say they are a bang for the buck champ
Racer
Joined: Oct 2009
Posts: 324
Likes: 0
From: Dallas, TX. 75061
1. Why even build the motor if you arent going north of 700rwhp? A lot of people have made that much on the stock ls2/3 bottom end.
2. Why even build the motor if you arent going to upgrade some of the bigger items like the rods?
Consider buying a meth kit for a little more safety until you feel like building the motor up all the way. I just couldn't see myself doing R&R + replacing just the pistons and not doing the rods.
2. Why even build the motor if you arent going to upgrade some of the bigger items like the rods?
Consider buying a meth kit for a little more safety until you feel like building the motor up all the way. I just couldn't see myself doing R&R + replacing just the pistons and not doing the rods.
Thread Starter
Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
http://store.hkracingengines.com/pro...products_id=62
Just one place to buy them. I'd use these all day over stock, but yes there are better rods out there. I'd say they are a bang for the buck champ
Just one place to buy them. I'd use these all day over stock, but yes there are better rods out there. I'd say they are a bang for the buck champ
Goal is a reliable driver that she can enjoy, yet be one of the fastest streetable Gen 1 Camaros around. With even a good running big inch gen 1 big block, they can't hold a candle to one with a well built blown gen 4 LS motor. I have some neighbors that have done the gen 1 to gen 4 swap and they say it's not too bad.
Last edited by old motorhead; Jan 24, 2013 at 01:27 PM.
Drifting
Joined: Feb 2006
Posts: 1,585
Likes: 15
From: New Hartford IA
It's actually a SBC rod, but will work fine with most aftermarket pistons. The difference is that the SBC rod will have some offset in the small end where a ls rod is stright up. It's a very small amound and and you just want to check clearance at the piston. Keep in mind that running a .927 pin rod will open up piston selection a LOT.
I'm either a all in or do it on the cheap type of guy. Heck the stock rods with stock bolts might even be good enough for you, but I'm not sure what level you will be happy with power wise so.... You might need to have something done on the aftermarket rod also so you can't rule that out either.
I'm either a all in or do it on the cheap type of guy. Heck the stock rods with stock bolts might even be good enough for you, but I'm not sure what level you will be happy with power wise so.... You might need to have something done on the aftermarket rod also so you can't rule that out either.
Thread Starter
Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
It's actually a SBC rod, but will work fine with most aftermarket pistons. The difference is that the SBC rod will have some offset in the small end where a ls rod is stright up. It's a very small amound and and you just want to check clearance at the piston. Keep in mind that running a .927 pin rod will open up piston selection a LOT.
I'm either a all in or do it on the cheap type of guy. Heck the stock rods with stock bolts might even be good enough for you, but I'm not sure what level you will be happy with power wise so.... You might need to have something done on the aftermarket rod also so you can't rule that out either.
I'm either a all in or do it on the cheap type of guy. Heck the stock rods with stock bolts might even be good enough for you, but I'm not sure what level you will be happy with power wise so.... You might need to have something done on the aftermarket rod also so you can't rule that out either.
Drifting
Joined: Oct 2006
Posts: 1,984
Likes: 16
From: Amityville New York
#7 Rod broke and made a small hole for the piston to pass through the block but 7 pistons,7 rods, the cam and all the lifters are still like new, the motor had 2k miles on it and was making 738rwhp with a Procharger DISC.