yotaracer

New guy here... even though i dont feel new, ive been creeping for weeks on this forum looking for answers and gaining knowledge. ive tried searching everywhere and every thread leads to a dead end or doesnt fill in every piece of the puzzle. Im building a mild reliable 98 or so LS1 block for my off road prerunner truck. I would like to know what combo of rod and piston I would need to run in order to have a floating pin setup. doesnt need to be forged, if anything just the rods since it wont be seeing any boost and rev limiter will remain stock. stock or hyper pistons should be find. ill be running somewhat stock 5.3 heads with a tr224 comp cam FWIW. THANKS in advance.

KCS

iTrader: (20)

The later model stock rods are floating pin, so that's the easy part. The trick is finding floating pin pistons for the stock rods. I don't know if any of the stock 5.7L pistons had a floating pin and I haven't seen any of the hypereutectic pistons like that either. Wiseco has some forged pistons that would work though.

yotaracer

I found a set of keith black pistons that claim to be press or floating with .943 pins. I just have a hard time justifying the cost of forged pistons on a somewhat stock motor. I
http://www.summitracing.com/parts/ue...-std/overview/ im not sure what use shallow rings means though...

91Camaro1LE

iTrader: (1)

I have a set of floating rods for sale from an 06 LQ4 let me know if you need them.

Shaggykjb

I went with JE pistons 3.905" and the beefier ls2 rods with the floating pin. Came out perfect, but those forged pistons were $600. They came with pins, locks and rings though. I've got a set of 3.898" pistons from a Corvette. I think they might be floating pin.

KCS

iTrader: (20)

Hey! Those look like they would work. There should be an oversize avaialble too (.25mm?) if you have the funds to have the cylinders honed with a torque plate.

I'm guessing shallow rings means the rings grooves aren't deep so a ring with less radial width would be needed. I'm sure there's a PN that's recommended to be used if you do some more digging.

.boB

iTrader: (1)

Forgive my ignorance, but why? If everything is otherwise stock, rev limit is low, and reliability is the key, why do you insist on floating pins? Stock engines with pressed pins last just about forever.

I don't know a lot about the LS engines, that's why I ask. But with a Ford motor that I'm more familiar with, floating pins would be a waste of money.

yotaracer

That was gonna be my next question... Are floating Pistons really Going to be worth it ? I just wanted them because of all the hype around upgrading to them and even gm upgraded to floating pins. Has anyone heard of pins backing out ? I have more piece of mind with clips. I would do scat I beam rods and mahle or speed pro Pistons at that point I suppose. What are your guy's thoughts?

KCS

iTrader: (20)

The floating pin GM rods are more robust than the pressed pin rods, so there's is something to it when you're talking stock rods. Other than that, I think that the floating pin setups are easier to assemble.

Quick Ranger

iTrader: (2)

The floating pins allow you to assemble on your own, pressed pins really aren't that easy to do yourself, usually need a machine shop.
Rockauto does sell a floating pin "LS6" piston replacement, but they are stupid expensive.

yotaracer

So if I end up with aftermarket pressed pin rods and Pistons you think I'll ever have any issues? Most mileage this motor will see is 10k Max.

KCS

iTrader: (20)

No, but with the aftermarket stuff, there are more options with the floating pin. Plus the aftermarket mostly uses a smaller .927" x 2.250" pin which is lighter than the stock .944" x 2.500" pin.

yotaracer

I was able to find bushed .927 pin rods but I couldn't find stock size Pistons for .927 pins. Maybe I'm missing something?

KCS

iTrader: (20)

"Stock size" like 3.898" bore? Most are going to be 3.902-3.905"

yotaracer

So I hone the crap out of it to make it .005 bigger?

KCS

iTrader: (20)

Well, the idea is to have it professionally honed with a torque plate to get the cylinders straight and round. It doesn't take much at a machine shops and costs about $200. No telling what the cylindrs would end up looking like if you used some sort of hand tool hone to take out .005".

yotaracer

Yea I wouldnt hone.005 by hand ever. Being a machinist (not motor) we only ever hone to open holes .0002 or so. I've read my year motor can't go bigger than .005? I don't see how .0025 each side thinner sleeve will crack em (if I have bored .01)? Especially without a bottle or boost.

KCS

iTrader: (20)

It's not that and extra .001" or so will cause the sleeves to crack, it's that there just aren't too many piston options for anything over 3.905". You don't want to go .030" over though, even if there was a piston available.

Quick Ranger

iTrader: (2)

Mahle, JE and Autotec all make a 3.898 bore piston that uses the aftermarket .927 pin. These all have valve reliefs in them.