5.3 L33 To 5.7 Ls6

[Sleeper S10]

Hey, Could use some help.


I found a shop that has two LS6 blocks. One new for 1200 Canadian and the other used 600 and they will take my motor on a trade which is good and my 5.3 cleaned pistons and new piston rings.


The shop owner was "Difficuilt" over the phone and never heard of a aluminum 5.3 L33 being similar to a LS6 and doesn't feel my parts will carry over, even though I read will from reading several posts they will/ should...


Question's:

Now even though the main crank for the L33 is the same GM #12552216 just like the LS6's, will I have to have my main crank rebalanced for 5.7 pistons?

Or if you know of anything else to be aware about, please let me know/ thanks lots!!!

[pwtr02ss]

All of the cranks are the came as far as ls1/6 5.3/6.0 as far as I know. It shouldn't need balancing either.

[generics10]

you can use your crank, but you have to have it balanced to match the weight of the new pistons/rods...

[Kampz69]

did you ask them how much it would be to bore your current block?

EDIT: also, if that one owner is a prick over the phone, and doesnt know the blocks are very similar, should be avoided.

[Sleeper S10]

Quote: Originally Posted by Kampz69

did you ask them how much it would be to bore your current block?

EDIT: also, if that one owner is a prick over the phone, and doesnt know the blocks are very similar, should be avoided.

i didn't ask if he could bore my block, i was told from another machine shop that I couldn't and also from reasding posts on the LS1 forum.

I found this on cranks but am still confused.





Crankshafts
There were only two different strokes used for the entire Gen III family, so the cranks should be pretty straightforward, but it's not that easy because there are two different flange widths and one crank that has three or four different bobweights to deal with.


5.3L Cranks
The 5.3L engines all came with automatic transmissions, so they all had the 12552216 casting with the narrow flange. This is the same casting that was used in both the 5.7L and the 6.0L, but it's balanced specifically for this application, so it has its own unique GM part number. We don't know what the bobweights are, but our sample piston weighed 406 grams.

5.7L Cranks
The 5.7L had the same stroke as the 5.3L, but the cars always with came the narrow flange, so it had the same 12552216 casting that was used for the 5.3L and 6.0L. The 5.7L cranks weighed about a pound less than the others because they had a 24.5 mm hole drilled right through the center of the second, third, fourth and fifth journals. We're pretty sure that the balance was unique to this application, because the pistons weighed 434 grams which is more than the 5.3L and less than the 6.0L.

[Kampz69]

im pretty surprised that you cant bore that block...not that im doubting you of course, but can you post some links to where you read that? im curious.

[Sleeper S10]

i was told an iron block could be safely ported not aluminum. i found one post where my l33 was ported and that person ran into problems.

here is a reply from a corvette/camaro club.


"Only the iron 5.3L can be safely bored to 3.90"
We have a good used LS1 block $600. New LS6 block $1500+tax"



if i come accross more i will post them, it's tough at work.

[Sleeper S10]

i will take a look at this one place that has a used LS6 for 600 and mentioned for me to bring in my block, he will give me something for it.


maybe instead of balancing my crank i best get a hold of an actual LS6 crank.

[Kampz69]

i gotcha, i just assumed with the thicker sleeves it would be possible. i swear i remember reading threads posted about it too...

[Sleeper S10]

i couldn't find one clear post on someone doing it.

also figure the cost of a bore i might as well try for a trade in blocks.

thanks for your help

[Kampz69]

thats true, if you can trade yours for that used block it shouldnt cost much, most likely less than what it would cost to bore a block.

[Sleeper S10]

just a write up i found...



"The cast iron blocks have thick walls so they can be bored up from the 4.8L/5.3L standard bore of 3.779? to 3.893? to make them into a 5.7L standard bore block if the additional weight of the iron block isn't an issue, but the aluminum blocks shouldn't be bored over .010 according to GM."

[pwtr02ss]

what tooth reluctor(sp?) wheel is your crank? Maybe thats what he was refering to being different from an ls6.

[Daveman2]

IMO as stated, I'd try to find someone that has done this kind of work before, there's nothing worse than trying to work with a shop that has an equal or lesser amount of knowledge about your parts than you do

[Kampz69]

Quote: Originally Posted by Sleeper S10

just a write up i found...
"The cast iron blocks have thick walls so they can be bored up from the 4.8L/5.3L standard bore of 3.779? to 3.893? to make them into a 5.7L standard bore block if the additional weight of the iron block isn't an issue, but the aluminum blocks shouldn't be bored over .010 according to GM."

that i believe for a true LS1/6 block - or even other aluminum blocks - but they already have thinner sleeves. the sleeves on the aluminum 5.3's are much thicker, which lead me to believe that they could be bored out to standard 5.7l specs.

[Sleeper S10]

It has a 24x reluctor

[Sleeper S10]

so would anyone know if all my L33 parts would carry over to a 5.7 LS6 besides the main crank which I will swap/ trade for and I would need different pistons/rings?


The rods and the heads are the same.


Thanks

[art]

The 5.3L CAN be bored to 3.898". Only the 5.7L LS1/LS6 are reccommended .010" hone due to the already thin sleeves.

All your L33 parts will carry over except for the pistons/rings. The 5.3l crank and rods will work for your 5.7L build. You will need to rebalance your rotating assembly due to the change in wieght from the new pistons

Only the 4.8L had different stroke and different length of rods.

Becareful with the machine shops. If they are not able to give you correct info, they may not have enough experience with the GEN III/IV GM small block engines. It doesn't mean they are not a good shop. You need to be informed as well as the shop.

If you are not in a hurry to get this done, I would reccomend that you read the few LSx books out there. It is very useful info that will only help you make better informed choices. Good luck

[Kampz69]

art, what about the aluminum 5.3's? do you think they can be safely bored to the same 3.898 spec?

[art]

Yeah. I have one of each in my garage and the aluminum block has some very thick sleeves. I posted this info in someone elses thread.


The aluminum 5.3L blocks are considered a "budget" LS6 block since they are essentially an LS6 casting with thicker sleeves to create the smaller bore for the 5.3 This info is in one of the LS1/6 books.

I think the GEN IV 5.3s are the same as well only they have provisions for DOD.

I believe all the aluminum blocks after '99 can be bored to 3.905 for 383 builds.

[Kampz69]

thats what i had always assumed...thanks for the info art

[CODE4LS1]

My '98 C5 was bored to 3.905 safely when I used to have my 383, maybe I was lucky.