Description: Yes! This is the rare 454 LS-7 engine. (7.4L/ 12.25-1 compression ratio) sold over the counter from 1973-1991 by GM. Supposed to go into a 73 Chevy Chevelle but could not pass the EPA emissions “smog” test. One of the fastest big block’s Chevy made and goes by a popular nickname as the “Gorilla” or “Torque Monster” of Chevy motor’s. You get everything from the oil pan up to the carburetor (excluding headers) (Ready to fire up). Tons & tons to list. Original receipt added to photos, my father is the original owner of this engine since 1991 when it came in a crate. Has about 10,000 miles on its life span before rebuilt. Yes you read that correct only 10,000 miles before it was rebuilt in 2023. PN 3965774, 454CID, 12.25:1 compression, 4 bolt main block, 5140 forged steel crank, w/cross-drilled mains 3963524, 4340 forged steel connecting rods with 7/16 in. bolts for pressed pins, 3963552, forged high dome pistons, open chamber cast iron heads 6260482, balancer 3963530, standard flywheel 3993827, engine suffix XCH. (All bottom end is still original forged steel) We just had it torn down and re-built back up by Pro Auto Racing in Crown Point, IN! New Howard’s retro-fit Hydraulic Roller Cam .680 Lift @ .050 (247/254 duration). Howard’s roller lifters, Comp Cam push rods, Comp Cams Ultra Pro Steel magnum roller rockers. Engine was primed and placed on test stand with 110 race fuel for first fire up. Hot tanked engine, original Crankshaft was ground .10 under with King Race bearings. New Manley Piston rings, gapped safe up to 200+ shot of NOS. New high volume oil pump/standard pressure. Valvoline 20-50W oil. New 168 tooth SFI Flywheel. (TH350/TH400 bolt pattern). Block and Head surface were cleaned up. Engine has never been decked. The cylinder walls were ball honed to be freshened up. (had .1 or less taken off the surface to keep original pistons) Original TRW Pistons, original connection rods, Heads are original 188 Rectangular Ported (Aka 990 Chevy BB heads). New valves, 4 angle valve job. New Hydraulic Roller double valve springs. (180 on the seat/425 open pressure) Heads have been ported/polished/match flowed to a Edelbrock Jr. 454 mid-rise single plane aluminum intake. Intake was also ported for more air flow. Nitrous lines are direct ported into the intake and was made for a 300 shot kit. (Older style Moroso Nitrous system) (direct ported lines that are built in will come with engine but not entire nitrous system) Holley 950 Double Pumper carburetor jetted for the race track. It has Taylor Made Race 10.4mm wires, MSD HEI distributor. NGK spark plugs gapped at .43 Our LS7 has been ran in our 70’ Nova since 1991 and has about 200 miles on this re-build since June of 2023 and works phenomenal. I can send videos for serious buyers to show it running and from our track day at US41 drag strip. Full weight 4200LBS car, it ran 11.90s/12.00s at 36 degrees of timing. (Max timing on this engine build is 38 degrees) We did use a 150 wet shot of nitrous, timing was cut back 8 degrees at 30’ and it ran 7.00’s 1/8 mile & 11.10s 1/4 mile. (Rev’ed out to 6800-7000 rpms) Timing has been lowered back down to 30’ degrees for street driving. It can be driven on 93 octane from a Shell/Mobile gas. We run VP race fuel leaded 110 at the track. This engine is known to be the “gorilla build” of the entire Chevy Big Block era due to its durability and was the one of the fastest factory big block’s they made until the 2000’s. It makes its peak torque at 5000 rpms and can be shifted to 7000rpms. 525HP/600TQ natural aspirated from the factory. We Asking $12,000. We will cover shipping costs up to $1,000 in the USA. It will probably take us a month to get it out of car and placed onto an engine stand to be shipped out. Pick up in Chicago to save yourself $1,000 off and have it asap in your possession. Reason for selling is we are looking to upgrade to a bigger cubic inch engine. Some trades are welcomed if you are trying to trade a “turn-key ready” 632, 572, or 555 dart engine. Thank you all for looking at a piece of history.
Price: 12000 USD
Location: Chicago, Illinois
End Time: 2023-12-26T20:21:02.000Z
Shipping Cost: 0 USD
Product Images
Item Specifics
Returns Accepted: ReturnsNotAccepted
Brand: GM
Type: Engine Long Block
Interchange Part Number: 396 427 L88 ZR1 ZR2 LS6 LS5, xch
OE/OEM Part Number: 3965774 XCH
Block Type: V
Number of Cylinders: 8
Number of Valves: 16
Engine Size: 7.4 L
Manufacturer Part Number: 1966 1967 1968 1969 1970 ls6 6272990 3999289
Country/Region of Manufacture: United States
Fuel Type: Gasoline