Ok.. I am wanting lost on these ls rods.. I know that the rods are very weak, but I am trying to do ls vtec and i was wondering if the ls rods with arp rod bolts and getting them cryo treated will be strong enough.. that is what i am wondering. I do not want to get eagle rods, but if the ls rods are not going to be strong enough I am going to have to get them.. What else should i do to the rods to get them to with stand the stress of reving to a least 9500 if i make power all the way up there..

 

First you need to figure out how "you're going to make power all the way up there"... when most of the other LS/VTEC builds out there do not. Try reading up on the "reliable LS/VTEC" build thread in the FAQ's at the top of the page.

 

i have but it does not tell me if the rods will with stand that about of stress.. i have done lots of research, but i can not find a real answer on it.. that is all..

 

My LS VTEC I just built has LS rods with ARP rod bolts. I got my rods shotpeened at a local shop which was around 50 bucks but not too sure since I had a lot of stuff done like getting the rotating assembly balanced so the bill was one big price.

Shotpeening isn't really needed but I wanted to be extra safe since I'm rev happy.

 

Ok, well what makes you so sure that you'll be puting that kind of stress on those rods? What is it that you plan on doing with the car?

 

Just as a reference, my GSR block with LS crank and rods(with ARP rod bolts) revs to 9k RPM daily, over 70k miles and making around 190whp (estimated 190 whp due to my buddy's very similar setup that made 193 whp). My main clearances with ACL bearings were .0015-.0019", rod clearances with ACL bearings were .0017-.0020"

 

OP, no a stock ls rod with ARP rod bolts is not advised for trips to 9500 rpm. The big end will oval and you will eventually either spin a rod bearing or break a rod.

 

ok.. so i guess it is not good to rev that high.. i am not saying that i will rev that high.. but i am trying to get the right parts to rev that high if i would want to make more power and rev that high... what is the highest i should rev the ls rods with arp rod bolts.. and they are going to be croyo treated??

 

I am not sure that i am going to be putting that much stress on the motor, but i am trying to see how much stress the ls rods can handle... i am trying to just build a daily driven b20 vtec..
my setup might be:
84.5mm rs machine pistons 11:1 compression
ls arp rod bolts and cryo treated
gsr head port and polished
skunk2 pro series valvetrain
skunk2 pro series stage 1 cams or stage 2 cams
hytech header

 

Cryogenic treatment will improve strength but not stiffness.

 

so should i just get eagle rods.. or am i going to be good rev to a least 9k with the upgrade on the rods..

 

I recommend eagle rods over stock ls

 

if youre serious about building a nice motor, get the crower maxi-lights.

i cant really tell if youre looking for the best choice or if youre looking for someone to tell you that what you have is "ok". thats the catch-22 of these boards.

 

^^^Better yet Carrillo Pro A.

 

i dont get it , you spending $2000-3000 in parts but you wont spend a extra $200-300 for a set of eagle rods...

sure you can run stock ls rods to 10,000rpm if you really want to. but the question is how long will it last

 

x2 on the maxi-lights, love 'em.

 

it's actually only add a few extra $$$$$
a new set of eagle rods usually come with ARP rod bolts for $300

Try to think
Your stock rods need to be shotpeened, re-condition, and need new ARP rod bolts
these all add up as much as new eagle rods already

Why not get a set of new eagle rods to save headache further down the road?

 

It's all in the machining. If you build it right, the motor will last. I dont see LSV blocks/rods fail too often if done corectly. Seems to be the head, or assembly error that causes failures. I have stock LS rods and ARP bolts in my LSV.
Worry more about the torque curve then spinnig "9500 RPM at least". I mean who really cares how many RPM you can spin.
Obviously eagle, crower ect. are better rods them OEM. but MOST (not all) LSV failures seem to be rod bolt failure or head failure. Dont see many post about throwin a rod through the block on a LSV. Again I am not saying it does not happen, just seems kinda rare. and again Crower, Eagle, etc are better rods then OEM though.

Nick

 

ive been running LS rods with ARP bolts paired with high comp pistons. almost 30k miles on the motor, and its never seen a quiet day. no problems whatsoever. even though im tuned to 9300 rpm, i shift around 8900. theres no reason to pull any higher.
like previously stated i would figure out how youre going to make power at 9500 first

 

Making power at 9500 is more of a problem than turning it that high. 9000 seems to be relatively safe on ls rods that have arp bolts and have been shot peened.