Soo im considering running forged 9:1 drop in pistons on the stock rods with my initial turbo setup build. I plan to build a 400+ CI engine down the road, but i want to be safe for the time being before that happens and replace the boost unfriendly stock pistons with some JE's. I currently have Katech rod studs installed and will use them with the forged pistons. What kind of HP/TRQ can the stock rods handle? I know the stock pistons are decent at 550 and can be pushed to 600, and some people have gone beyond 650. Risky **** for sure, soo with forged pistons, is 700 rwhp/trq feasible?

 

spend the extra $500.00 and put in some forged rods too.

 

Yea then i have to do new rod bearings, kinda looking to try a budget/safe setup while on small cubes for ***** and grins. I will wind up using the 346 for my prerunner down the road after i put the 400+ CI motor in my car. It wont need forged rods in that, haha.

 

So your sayin your gonna remove the stock rods, remove the pistons from them, replace with aftermarket pistons without balancing & reused the old bearings?

Sounds like a budget plan for disaster honestly.

 

I saw a car on GM High Tech Perfomance running stock rods on a turbo ls1 at the 700 rwhp level. But guys here have done that on stock pistons as well.

 

Get the forged rods right now. You can re-use them in your 400+ engine.

And for Pete's sake, dont be a tight ***! Get new bearings dude! Thats just stupid to re-use bearings when they are out anyways.

 

+ eleventy billion

 

im at 584 with stock rods and forged pistons, i know it was a mistake but also want to know how hard i can push these

 

Lightweight stock rod + Heavier forged aftermarket piston = More stress on the connecting rod! Your forged pistons will be more durable, but you've effectively put more stress on the stock connecting rods. The rods would have been better off dealing with the lighter stock pistons. Plus, you will definetly have to have the rotating assembly balanced again just by changing pistons. I understand saving a buck, but you gotta draw the line somewhere. If your gonna buy the pistons, rings, pay for machine work to hone the bore for the new piston / ring combo...AND BALANCING...you might as well do the rods and get it done right the first time. If it were me, id leave it stock, or throw some rods in when changing pistons.

 

damnit, youre right about the weight differences. I kinda forgot about that key ingrediant... Prollly just shoot for 600rwhp and call it a day on the stock ****. BUT that money i could use for pistons,,, i could buy a used alluminum 6.2L escalade block and start the 400+ build...

 

sounds to me like you are lost. sit down and really thing about of what you ACTUALLY want and what you CAN afford.

 

I understand running the completely stock longblock... Many here have...


But if you have the money and the time to rip that block open anyway, how could it hurt to throw in a nice refresher of bearing, rods, etc?

I'd either build the block, or not...

 

dumb...i doubt youd make over 750 for very long before bending a rod

anytime you pull a rod cap apart replace the bearing...cheap insurance

 

No you are lost, you live in CANADA! lmfao...

 

Wow great response to great advice

 

I'd say at the least put some good rod bolts in even if you leave everything else stock, which is what I would do. From what I've read/been told/seen/etc. the stock rod bolts are one of the most common reasons for failure of the stock shortblock.

 

stock pistons will fail under boost before the stock rod bolts...

 

My LS2/L92 headed engine made 623 rwhp with 12 deg timing at peak torque and 11.5:1 afr nice and safe. Drove it for 2 months, raced it etc. Put it on the dyno last night and did half a dozen pulls tidying up the fuel map after installing new fuel pumps and it went bang after 10 runs spinning it to 7000rpm plus. Motor has 10.8:1 comp plus T trim and other bits had rod bolts in it stock rods and pistons. Motor never had detonation issues ran cold plugs very safe tune so had more in it just kept it 20 hp less then optimum. So yeah I found the limit. If I was building a motor specifically for boost i would run 9-9.5:1 comp forged pistons and rods arp bolts throughout lots of boost push the engine to the edge with the tune then back 20hp for safety and it will last. Fi u have to do things properly. Save ur money on ur fancy valve train, cams etc stock LS2 cam will makes power no probs with FI on low comp.

 

is anyone else running forged pistons with stock rods?

 

Bingo!
Thanks for saving me all the keystrokes !!!
Leave the long block stock in grenade mode, or build it for real and be done with it. Heavy forged slugs + flyweight stock rods = TROUBLE.
Drop the max rpm by 1k and it might live for a while.....might.
Save your $$$ and do it right.
You will save money in the long run.