Well we could always ask Pat if we could do a website sponsor via the members. I would be up for something.
LML How strong/reliable are lml delipped pistons
- Thread starter nc-12vpower
- Start date
Well we could always ask Pat if we could do a website sponsor via the members. I would be up for something.
there is another thread somewhere where someone had a set of pistons machined to accept a regular carillo rod, so all the machining was done on the piston and not the rod. i kinda liked that idea but honestly if one can afford carillo's wouldn't one use more expensive and proven pistons too like mahle or fingers
I have a LML engine that was in a fire. My 14yr old son is learning about how the duramax engines come apart and go back together. We will have it totally torn down this weekend and i'll take some photos of the differences comparing to LBZ rods and pistons.
I'm then going to put it back together and will try to throw it into one of the race trucks and put it on our Dyno. We have the fuel and air to break almost anything.
I'll be happy to post up the outcome.
I'm then going to put it back together and will try to throw it into one of the race trucks and put it on our Dyno. We have the fuel and air to break almost anything.
I'll be happy to post up the outcome.
That's good news Rob, been following this thread, just curious as others just how much in a real world situation these lml pistons will hold.
Considering I don't have a cash tree blooming at the house, the idea of a member sponsored fund sounds promising.
Considering I don't have a cash tree blooming at the house, the idea of a member sponsored fund sounds promising.
this isnt the truck that made it out to the alligator dyno day to test the new efilive is it? that was a nice truck
either way keep us updated that sounds sweet :thumb:
Yep, I was going to link all the open threads on topic earlier but then I thought to myself, "why am I going to waste valuable time in my work day to hold people's hands" 
I would be concerned about how much that would weaken the piston. As I understand it, the LML pistons have a shorter wrist pin than the other Duramax pistons. That is why the small end of the rod is narrower. I would worry that machining the piston to fit an un-modified rod would cause it to weaken the wrist pin area or possibly cause it to flex. Don't really know, but on an already questionable part, I would be hesitant to remove any structural material.
This is all my thoughts on the subject without ever actually holding an LML piston in my hand. Take it for what it's worth.
it almost seems pointless to run lml pistons in a engine build think about this most of us keep pushing and tinkering on our trucks so y spend a fair amount of money on rods machine work and so on and then put lml pistons into it you may save some money but what if one cracks then what did you really save when you could of just ran a good quality piston from day one and for everyone saying all i want is a xxxhp you probably said that when u first got efi live and look how long it took before u wanted more
couldnt agree more rather be safe then sorry but its your choice :thumb: the way i see which some may disagree peace of mind is worth more then anything
Yep, I was going to link all the open threads on topic earlier but then I thought to myself, "why am I going to waste valuable time in my work day to hold people's hands"
Looks like you waste all your "valuable work time" on this forum anyways.
That's the problem, there is no "peace of mind" piston out there that has piston cooling oil passages that has proven any better. Or at least what most think, many have cracked Mahle Race Cast... Only ones with no known failures currently are Fingers Oval Mahle cast, and lml's that I know of. And I wouldn't put forged any brand in a daily driver 1000hp+ twins or triple truck that I intend to put 10,000+ miles a year and tow at 20,000+ lb gross on a normal basis...
If I did it again, I would use Fingers cast from Mark's results, but others feel there isn't enough sets out there proving themselves knocking on the 1000+ hp mark on occasion.
What does a brand new set of lml pistons cost? I assume oval cast are around $1600-$1800? I could be wrong on that, but lml's would have to be dirt cheap to justify $800 in rod machining, like $50 a hole with rings. Because at $400+$800, it would have to be a damn good amount saved to justify making a one off set of rods, However, if they were proven strong enough aluminium rods can be built dirt cheap compared to a saet of Carillos, Crowers, or Howards. My 65 Malibu with aluminum rods, lml pistons, big air, big fuel would be a fun 5,000 mile a year car and toy.
I am however, not a fan of aluminium rods in my diesel pulling application, because I feel we lug the engine too much at the big end, and the surging and loading/unloading the engine does during a pass...
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Just checked with GM. New LML pistons standard are $32.23 each. Wholesale is $23.88. Talk about cheap pistons. Might justify the cost of machine work
I think that for the price, Jon's pistons are the way to go in street driven truck, absolutely. Its a couple hundred more dollars than using LML pistons in the end, and you gain the performance characteristics of his bowl design.
These threads always get directed away from the original question because of the clash of opinions, but the original question was only asking how reliable have the LML pistons been. Now, everyone has found this site, correct? Everyone knows how to check PMs and call a phone number in someone's signature or vendor page I would assume....so how much more difficult is it to use the Search tab? How much more difficult is it to call people that have been using these pistons and talk to them to gain some information that is a little more credible than someone's internet post?
These threads always get directed away from the original question because of the clash of opinions, but the original question was only asking how reliable have the LML pistons been. Now, everyone has found this site, correct? Everyone knows how to check PMs and call a phone number in someone's signature or vendor page I would assume....so how much more difficult is it to use the Search tab? How much more difficult is it to call people that have been using these pistons and talk to them to gain some information that is a little more credible than someone's internet post?
i am building my motor right now with carillos and cut and coated lml pistons. In a post somewhere on the forum, i put the weight difference between the lbz and lml piston and the lml was considerably lighter. the wrist pin area is stronger in the lml. I went with these pistons was for one, my cost is $22 a piece. secondly, nobody knows how good they are, so i am trying them. everybody says run finger's pistons but at the start there was no evidence if those would be any good. sometimes you have to experiment and try new things. if i crack a piston, hopefully i will know the limits. i have no problem changing a piston (s) for the sake of learning. my carillos came from carillo made for the lml pistons. i also cut down aset of carillos to fit the lml pistons. i have a fixture machined up to put rods in to grind them down exactly where they need to be if anybodys needs it