• 5.7L Performance Stock Replacement Iron Long Block w/ Cathedral Port Heads 500HP

5.7L Performance stock replacement LS1 LS6 iron block 

Blueprinted GM block LM7 or Gen 4 5.3 core

King main bearings

King rod bearings

Thompson Motorsports single piece racing cam bearings

GM Nodular crankshaft polished and balanced core

GM connecting rods TMS remanufactured cores

Coated Hypereutectic piston set

Performance file fit rings

12 month unlimited mileage warranty with the purchase of a new Melling oil pump from TMS

This short block is rated to 500HP

GM Remanufactured heads, Pac 1219 valve springs, GM retainers GM Valves

243-799-317 Remand Heads
GM performance remanufactured valves
PAC 1219 beehive springs good to .625"
Thompson Motorsports custom ground Camshaft
Thompson Motorsports custom length Chromoly pushrods
Torque to yield head bolts
Melling Select High pressure oil pump
Billet adjustable timing set
Thompson Motorsports high RPM lifter set
GM Rocker assembly cores
GM MLS head gaskets
GM lifter trays

Thompson motorsports Professional assembly and 12 month unlimited mileage warranty

For warranties and policies: https://www.thompsonmotorsports.net/warranties-and-policies.php 

***If, turbo, supercharged, or Stroker motor please add a High Pressure/High Volume oil pump for warranty"(if you do not add this pump for these application warranty will not be valid)***


*A crate is not required for a customer pickup, only an engine stand*


Call for any questions: 972-853-2450

We are located at: 

545 Justin Pl.

Nevada, TX



All motors could require minor modifications for install (drill and tap holes or clearancing). These changes are minor and can be performed with simple common tools. Thompson Motorsports is not responsible for the work required nor does this warrant a reason for the return of the product, even in the case of a direct replacement. We are dedicated to customer service and are more than happy to help with the install in any way possible. Please feel free to call or email with any questions or concerns.


 All high performance motors will come with no VVTI or DOD. If the vehicle originally had either or both of these you will need to change to a LS2 front cover and LS2 valley cover to eliminate. You will also need to alert your tuner to the changes for PCM changes.

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5.7L Performance Stock Replacement Iron Long Block w/ Cathedral Port Heads 500HP

  • Product Code: A1-12
  • Availability: 999
  • $4,498.99
  • $3,999.99

Available Options

Tags: iron long blocks, long blocks, TMS long blocks