L83 All motor build

flyingfool · February 29, 2020

i'm just going off of what the GM techn told me buddy

i'm sorry he was comparing the rod length to the older 6.0, not the 6.2, my bad..

Edited February 29, 2020 by flyingfool

SierraHD17 · February 29, 2020

1 hour ago, flyingfool said:

i'm just going off of what the GM techn told me buddy

i'm sorry he was comparing the rod length to the older 6.0, not the 6.2, my bad..

The rods in the 5.3, 6.0 and 6.2 are the same length. The LT engines didn't change from the LS's 6.098" even though GM published they had initially. You can use an LT engines rod in an LS block with an LS piston... it's been done. I thought maybe they would have manipulated rod length in the 6.6 for the stroke but evident by my 6.6 rod it's not. I get a new 6.6 piston hopefully Monday as it came in and I just can't go get it to compare to my L86's existing pistons. I would have the whole rotating assembly but the crank has not been released for public sale yet...

flyingfool · March 1, 2020

shit, now your gonna make me do more homework

SierraHD17 · March 1, 2020

You can even use the LT crankshaft in an LS block... crazy huh lol. I wanted initially to do an L9H I have into a 6.6 with the L8Ts crank but getting pistons becomes an issue. I do build and have a lot of stuff. Makes talking about it easier when you can try it lol.

flyingfool · March 2, 2020

yes redesigning a custom piston to fit might take up all ones time in research and development , and your still sitting in the garage building. we'll see when these 6.6L start showing up at wrecker or when what they run in a crate.., some of the specs on them sound like they are designed for boost , the weakest link will be my 6l80

SierraHD17 · March 2, 2020

Yeah I didn't wan to wait and pay 10k for one that in 10 years will litter pick and pull yards here. This L86 needs a crank and bearings anyway so this works quite well. If I did nothing but the rotating assembly I would basically have a stock 6.6 but in aluminum however I want to keep compression closer to 12:1 and put a fairly large cam in it. See what I end up sticking it in.

truckguy82 · March 2, 2020

On 2/29/2020 at 3:43 PM, SierraHD17 said:

Considering I have connecting rod in my possession for a 6.6 that I ordered from the dealer yes I do know what I am talking about thanks. Do you? No.. you don't.

You can manipulate rod length but in this case its piston pin height. Center to center on that rod and an LQ4 rod are identical. Gm is cheap and does things as cost effective as possible... it's a stroked 6.2 and that's all there is too it. 401 hp and 464 lb ft with a timing curve allowing use of 87 fuel means severely detuned...

L86 All Terrain · March 2, 2020

2 hours ago, SierraHD17 said:

Yeah I didn't wan to wait and pay 10k for one that in 10 years will litter pick and pull yards here. This L86 needs a crank and bearings anyway so this works quite well. If I did nothing but the rotating assembly I would basically have a stock 6.6 but in aluminum however I want to keep compression closer to 12:1 and put a fairly large cam in it. See what I end up sticking it in.

What's your reason for wanting to stay around 12:1? Do you plan on boosting it after or running 87 octane? Or do you keep it down when doing a big cam?

Edited March 2, 2020 by L86 All Terrain

flyingfool · March 2, 2020

1;20 minute mark rods are 6 mm longer than the 6.2l engine. makes me wonder if you have the correct part number or if there has been a redesign or recycling of old parts at GM

he must of meant to say the crank is 6mm longer not the rod

Edited March 2, 2020 by flyingfool

SierraHD17 · March 2, 2020

20 minutes ago, flyingfool said:

1;20 minute mark rods are 6 mm longer than the 6.2l engine. makes me wonder if you have the correct part number or if there has been a redesign or recycling of old parts at GM

he must of meant to say the crank is 6mm longer not the rod

Yeah the crank stroke is 6 mm longer.. 98 versus 92 mm...nothing to do with the rods. People are clueless in these videos lol. My parts are correct.

SierraHD17 · March 2, 2020

2 hours ago, L86 All Terrain said:

What's your reason for wanting to stay around 12:1? Do you plan on boosting it after or running 87 octane? Or do you keep it down when doing a big cam?

Compression = efficiency. Hence why the 6.2 was 11.5:1 in the first place. More won't hurt and with direct injection the static ratio as well as the dynamic ratio can be raised substantially.

But my build isn't this guys and I am not here to ask about or debate mine lol. I have my own thread documenting as I go on Performancetrucks.net.

Edited March 2, 2020 by SierraHD17

00pooterSS · March 6, 2020

On 3/2/2020 at 1:03 PM, flyingfool said:

1;20 minute mark rods are 6 mm longer than the 6.2l engine. makes me wonder if you have the correct part number or if there has been a redesign or recycling of old parts at GM

he must of meant to say the crank is 6mm longer not the rod

When deck height remains the same and stroke increases you shorten the rods, not lengthen. That would be your first give away that the dude mis spoke.

dieselfan1 · March 7, 2020

i'm just going off of what the GM techn told me buddy

Sent from my Pixel 3 using Tapatalk

I heard it from a friend usually means it's bullshit

flyingfool · March 7, 2020

i would like to hea

On 2/29/2020 at 7:25 PM, SierraHD17 said:

You can even use the LT crankshaft in an LS block... crazy huh lol. I wanted initially to do an L9H I have into a 6.6 with the L8Ts crank but getting pistons becomes an issue. I do build and have a lot of stuff. Makes talking about it easier when you can try it lol.

I'de like to hear more about the LT crank swap, got any more tech info?

SierraHD17 · March 7, 2020

There isn't much out there.. much like what i am doing. I could do a video someday I guess lol. There is one local guy I know who did a video maybe a year ago if I can find it on YouTube putting a gen v crank in a gen iv 5.3 block. The LT aftermarket sucks... parts are limited on an engine that's been around for 7 years now. Like I mentioned on PT even simple things like thinner than stock head gaskets are non existent. No matter though as I will forge forward anyway lol. A friend of mine finally got his new company truck and it's a 6.6 HD so I want to see what casting number the heads are and if it's a L86/LT1 number. Even if its not it could be the same head and be like the 821 in the LS3 and the 823 on the truck 6.0 and 6.2...same head... different valve material lol.

Edited March 7, 2020 by SierraHD17