so ive been really thinking bout buying connecting rods for my LS vtec set up. i have a LS block honed to 81.5 with rs pr3 pistons with oem crank and oem LS rods. will a stock LS rods handle daily driven and rev to 9k? or should i just save bit more and buy after market connecting rods. thanks guys

 

ARP rod bolts are about $50-60, the machine shop I go to charges about $50 to install ARP rod bolts and recondition the rods afterwards. If the rods need balancing that's about another $50-100. So for $150-200 you'll have oem rods that can rev to 9k rpm but they won't have the strength to resist twisting like a set of forge rods for about $300 brand new. Good rods like Manley are weight matched to +/- 1.5 grams and the bore ends are machined to precise clearances so they should be ready to install w/o any machine work needed.

 

To add to the good info all-mtr-teg just stated, nor do they have the stiffness to resist ovalizing the big end. When you rev to 9.0k, the load increases by 75% over the 6.8k rpm redline of a stock ls. It is true ARP's will improve joint strength but the big will see is enough load to permenatly distort the rod by more than 0.001". The consequences are a eventual spun rod bearing.

 

and to add even more; an aftermarket rod will not mate to the factory piston so he would have to order aftermarket pistons as well. I paid a total of $145~ to get my Ls rods crio treated and arp bolts. my current gsr block with LS crank and rods is rev limiting at 10k and we stop there cuz i was shitting bricks.. it saw 10.5k about 7 times; still making power up there, but i decided to turn down 9bhp for my peace of mind.

you decide whats best for you, i just gave you my experience, just know that the factory rods could take it, and if you decide to go aftermarket you would need pistons too.

 

i just wanted to say thanks guys, you guys are a lot of help

 

also i bought standard acl bearings, i was wondering if i should sell them and get bearing that are color coded to match my build? or is it ok to use standard size for all the rod and crank bearings?

 

depends on if the acl's will be within spec or not.

 

i also run ls rods, they were shotpeened and have arp bolts. im tuned to a limit of 9k, the year before i was only tuned to 8500.

at the track, for some reason my limiter was not set and im pretty sure multiple times i shifted at 9500 or so (i was off the tach sooooo....)

the motor has survived 4k miles so far, and i dont treat it nicely. would i trust it repeatedly to 9k+, probably not.

if you have the money for aftermarket rods get them, if not run ls rods and arp bolts, just know you cant rev to the moon.

 

thanks guys