LBZ piston replacement

[01 silver bullet]

Well the wifes LBZ finally let the headgaskets go, so I'm pulling heads, gonna do gaskets, studs, turbo etc but I think I'd like to do pistons while I'm in it
Question
Can I just pull the rods/pistons and put new lb7 pistons/rings on the stock rods and put new rod bearings/bolts in and call it good?
I'm looking for a good reason why I can't, as far as I can think there shouldn't be a problem, there's nothing wrong with the motor except blown headgaskets I just don't want to crack an LBZ piston, keep in mind the most truck will see is maybe 650 with the turbo (probly 4094vvt) and maybe around 40% nozzles, so I figure the stock LBZ rods and some Mahle lb7 pistons should hold up fine for around 600hp
Tell me what you think please! I don't want to tear the block down for machining I'll be at the end of my budget with pistons

 

[RPM Motorsports]

Rotating assy will be out of balance using LB7 pistons.

 

[WVRigrat05]

^ yep you'll have to have the rotating assy. Balanced

 

[matt78]

I'm no expert,my first 3 mods were a trans,turbo,and nozzles,cracked a piston in my lbz shortly after,within 6 monthes. I was racing the truck when it happened,anyways good luck with your truck.

 

[DMAXchris]

Can I just pull the rods/pistons and put new lb7 pistons/rings on the stock rods and put new rod bearings/bolts in and call it good?
I'm looking for a good reason why I can't

No. It will be out of balance like stated above. Machine work is very important and doesnt cost that much compared to buying a whole new motor when the one you cut corners on breaks. Get the cam & crank keyed, balance it, de-lip the pistons and have it align-honed. Shouldnt be more than $800-1000 and will make a big difference in how long it lives.

 

[redws6rocket]

Buy a set of fingers cast pistons, he can balance them and you can put them in and go.

 

[NC-smokinlmm]

I woud just put it back together and run it untill a piston gives up the ghost. It may last a lot longer than you think it will...

 

[01 silver bullet]

Ah those arent the responses I was hoping for lol I wonder what the piston weight difference is, I just don't have much time to have it down waiting for machining! Wonder if we weight matched the pistons and put back in the same holes? Damn I sound lazy, it's cause its my own, don't wanna work on my stuff after working on everyone else's all day!

 

[sickdiesel]

I would defiantly have it balanced bud. Don't just slap pistons on there and hope it'll be ok. Lot of money to gamble with

 

[xtremebikr04]

I would defiantly have it balanced bud. Don't just slap pistons on there and hope it'll be ok. Lot of money to gamble with

X2

 

[01 silver bullet]

Ya, I'm gonna do that if i do pistons, ill probably just do headgaskets/studs for this season and hope it doesn't crack a piston, it probly won't be over 600 this year, I think I'll still put a 4094 on it while I'm doing headgaskets

 

[Fingers]

Buy a set of fingers cast pistons, he can balance them and you can put them in and go.

I can weight match the pistons to each other. That is not the same as balancing the internals. Just makes it easier.

 

[malibu795]

Buy a set of fingers cast pistons, he can balance them and you can put them in and go.

I can weight match the pistons to each other. That is not the same as balancing the internals. Just makes it easier.

x2 iirc OEM spec balance is some where around +/-20gms? having it balance is usually +/-.5gms plus a balanced engine runs and revs better then factory balanced engine