are there any stock rods that are stronger then others? LB7vsLMM? ect.

I have to do head gaskets so while im there I am going to do ARP studs. was thinking if I already had the motor out, maybe there was some cheap ways to gain a bit of strength. I do not have cash for aftermarket rods or pistons at the moment. was hoping to do it all(motor rebuild) at once but head gaskets are gone and I have to fix it before winter comes around.

LBZ rods are stronger than LB7/LLY rods...not sure if LBZ/LMM use the same rods though. If you plan on running big power it would be better to save for aftermarket rods though..do it right the first time

If you were to go that route, I would put some LBZ/LMM rods and de-lip/cut your stock pistons to lower compression a bit. That should help things live a little longer. Could do main studs as well while you are in there to keep the crank from moving. As they are only like 300 bucks or something like that.

would love to put aftermarkets in, but at the moment the truck is my DD and I have to replace the head gaskets and dont have cash for aftermarket rods. was wondering around the classifieds and seen quite a few LMM rods for sale. thought maybe there would be a $2-300 benifit of newer rods.

truck in question is my LLY in sig.

posted at the same time...

thats kind of what I was thinking. how much are ppl paying to cut there pistons? main studs were also going to be done if I do start playing with the bottom end.

Buy some LMM/LBZ rods (there the same rods) Have your pistons delipped think you can get them delipped for $500, do main studs and heads studs and you should have a pretty stout motor, if built right, IMO. I think the LMM/BZ rods are a little under rated, you never hardly here of anyone bending one.

is an 06 lly have lbz bottom end? I read somewhere that the 06 lly's have lly bottom ends with lbz tops and detuned. I was always under the impression the only difference was, the tuning.

Yes 06 LLY's with the 6 speed trans have an LBZ engine.
LBZ/LMM rods are stonger than the ones in your 04.5
I think LMM rods would be safe at 600rwhp. I also have some forsale if your interested.http://www.dieselplace.com/forum/showthread.php?t=388034

Aren't the LML rods supposed to be pretty damn strong?

Sad part to this thing here is. If you add main studs you need to line hone the block. At this point your into new main bearing and rod bearing new rod bolt since you can not reuse the stock bolt from the stock rods. Also if you start deliping the pistons and changing the rods you should rebalance the motor. You will also need new flywheel bolt front and rear main seals and a few other gaskets. At this point you simple head stud and head gasket job just turned into a build that would cost you only 2 k more to do the right way and not look back.

I know head studs are a smart move, but at what HP do you really need mains?

I know head studs are a smart move, but at what HP do you really need mains?

X2! I'd also love to know

I know head studs are a smart move, but at what HP do you really need mains?

700+HP is were I recommend main studs along with rods.

I guess if your upgrading your rods its crazy not to do main studs while its apart.

So you're suggesting with proper tuning you're pushing some stock bottem end trucks to 700?

700+HP is were I recommend main studs along with rods.

So you're suggesting with proper tuning you're pushing some stock bottem end trucks to 700?

Yeap, have done it several times with success. There are no guarentees and drag racing seems to be the quickest way to destroy a stock lower end. I guess we will find out on my truck becuase it is definitely in the 700hp ball park and I am going to Topeka with it. And yes, if you have it apart to put rods in it, why would you not put studs in the lower end? Yes you will need to line bore it due to the extra load from the studs torque spec changing the main bearings oil clearances.

I guess if your upgrading your rods its crazy not to do main studs while its apart.


Hi i'm crazy :D seeing what stock main bolts will hold with a balanced motor with Crower rods and cut and coated pistons and head studs. when I ran the GT4202R and twin cp3 ran a 11.53 @ 116.92 on a 1.66 60' blowing all 4 M&H's off on a low tune. The 1/8 mile was a 7.35 @ 95 just shy of 96 and I hit 6th gear at the 1/8. The poor GT42 was sucking thru a 5" inlet that was cut back to 2 1/2 after having to notch it to fit around some home made tubing to get it running in time to race with the parts we had. Truck had the baby seat and hitch and all it it less spare tire and almost a full tank of fuel so just weighed in around 6980 with the heavy weight driver. This motor has alittle over 2 years on it and 31,000 miles of abuse.

If you are going to use main studs, why not billet caps right away? THEN you would line bore followed by line hone. Just adding studs you should be fine to line hone.

FWIW from 500-700HP is no mans land as far as I am concerned. Stock rids don't belong there as far as I am concerned and it is MUCH cheaper to do it now rather than wait for things to fly to pieces and risk ruining a good block.

Threads like this give people superman complex thinking that they can go nuts and have the engine survive when in fact it is a ticking bomb in most cases. I got away with it for quite a while with mine as have others, BUT there is a certain "knack" or "feel" for doing so...