Alright the gerbil in my head has been working overtime figuring out my setup for a balanced and blueprinted high compression 5.3L

So i figured through recon and junkyard searching that there is a 5.3L flat top piston in existance and it comes out of the LS4 for the Malibu SS and according to GM powertrain the bore and stroke on the motors are identical. the only difference is the crank snouts on the LS4 are shorter so i figure i can use an LM7 or L59 Block and crank with LS4 pistons and rods to achieve a higher STR without milling the **** out of my heads, they also have a different coating on the pistons called "graffel" or some crap. now i just have to figure out the part numbers for the Following items

LM7 Block
LM7 Crank
LS4 Rods
LS4 Pistons

and then decide on a ring package and get the entire assembley balanced and blue printed.

What do ya'll think???

 

Alright the gerbil in my head has been working overtime figuring out my setup for a balanced and blueprinted high compression 5.3L

So i figured through recon and junkyard searching that there is a 5.3L flat top piston in existance and it comes out of the LS4 for the Malibu SS and according to GM powertrain the bore and stroke on the motors are identical. the only difference is the crank snouts on the LS4 are shorter so i figure i can use an LM7 or L59 Block and crank with LS4 pistons and rods to achieve a higher STR without milling the **** out of my heads, they also have a different coating on the pistons called "graffel" or some crap. now i just have to figure out the part numbers for the Following items

LM7 Block
LM7 Crank
LS4 Rods
LS4 Pistons

and then decide on a ring package and get the entire assembley balanced and blue printed.

What do ya'll think???

 

Your putting alot of money in a 5.3l. Im thinking for what you are going to have in it you could have a 370 forged shortblock.

 

remember though i am going for the N/A 5.3L Record

plus in all honesty these parts will allow me to spin the dogpiss out of this motor with ARP 2000 rod bolts and a full balance with an aluminum flexplate

 

 

I dont know which parts or part number will give you what you want, but I gaurantee you that the LS4 did NOT come in the malibu SS. It was in the grand prix GXP, bonneville gxp, mone carlo ss, impala ss. The reason the crank is shorter length wise I'm sure is because it was mated to a FWD transaxle and not designed for rwd use...if the cranks are interchangable, you might be onto something. Just ou fo curiosity though, what are you trying to accomplish and if you are going to spend the coin on converting over an LS4, why not build a stout LQ9 or 408?

 

i am going for the N/A 5.3L record and i want to see what the power potential of the smaller bore motors are, i think i can dig deep into the 12's N/A with the setup i am planning

Oh and i'm not gonna convert an LS4 just bastardize parts out of it

 

As a start, you are gonna have to put that fat bitch on a diet. Some guys in RCSB wiegh a full 1000lbs under or more than your raceweight. (using what you posted in the weight thread of 6100lbs. If this is correct) In theory thats a full second on your ET. IMO your are starting your goal on the wrong platform. No offense.

 

Yeah i know beau, i'm putting the bitch on a diet but i really want to go after A/P's Record of 13.2 N/A which is the extended cab record. and my ego wants to dip into the 12's which i think i can as AP ran his record on stock heads and bottom end. or i could just give up and turbo the bitch since i have a nice turbo converter in already.

 

doesn't the L33's have flat tops?