jimmys434

what is the difference between a 5.3 and 5.7 crank they have the same stroke and use the same rods and bearings but the part number from gm is different whats the difference thanks

Bo White

iTrader: (59)

The balance is different because of the lighter 5.3 pistons. It is like the SBC 350 and 305 cranks, same crank but different balance.

Steve Bryant

iTrader: (1)

The LQ4/LQ9 6.0L versions both share the same basic crank with the 5.3 and the 5.7. However, the cranks are different part numbers for the same reason, the mass of the pistons/rods. The LQ4 with a CR of 9.4:1 has dished pistons and the LQ9 (which is the same engine otherwise) has flat topped pistons and a CR of 10.1:1. The stroke on all is 3.362".

Bo White

iTrader: (59)

The stroke size may be a typo I think. I understand that all have 3.622" except the 4.8 which have a 3.27" stroke.

jimmys434

so can i use a 5.7 crank in a 5.3 block with 5.7 rods and aftermarket piston if it is rebalance and will i need a new balancer or flex plat or can i use what i have looking to put into a s 10 got the 57 free bad block but every thing else was good and got 5.3 block for 25.00 so i would like to use what i have any help is greatful thanks

Bo White

iTrader: (59)

The LS1 style engines share the same rods too, 6.098, except the 4.8 which has a 6.278 rod. The pistons will not really be custom, just get a replacement 5.3 piston unless you want to upgrade. BTW, what is wrong with the 5.7 block?

jimmys434

Has A Bad Spot In It It Whas To Go Like 30 Or 40 Over To Clean Up And Cant Go That Far

Bo White

iTrader: (59)

PM me if you want to get rid of it.

jimmys434

I Will Right Now Tring To Find A Shop To Put One Sleeve In It

Bo White

iTrader: (59)

I would rather have it as is if you wanted to not use it for anything.