454 Ls7 Xch, Don't worry about authenticity, I have owned for 10 -12 yrs and know the original purchaser. A fuel issue can do that also. motortrend. The heads in this auction are BRAN NEW and have never had valves installed. Aug 27, 2012 · Production Chevrolet designed the LS7 454 beginning in 1970, but it was never placed in any vehicles that were sold to the public. Not installed in a car , just bought over the counter in a crate . This is the 12. I have been searching everywhere and I cant find an answer does anyone know? Source: 1986 Chevrolet Heavy Duty Parts Listing PN# 3965774 454 CID, RPO LS7, 12. Decided to service or overhaul your Chevrolet gasoline Big-block Mark IV 454 CID (7. Engine has never been fired. i verified this with a corvette history book at borders book store! but i have also read reports where some guys test drove a 1970 SS454 LS7. Technical Notes: Basic RPM range is 4400-7000; compression ratio 11. Heads are aluminum bowtie 14944861. Was your LS7 sold over the counter as a crate engine?? If it was then it would have the XCH stamped on it. 4 Bolt Find many great new & used options and get the best deals for LSX 454 Engine 740hp @ 7100 RPM Ls7 at the best online prices at eBay! Free shipping for many products! My goal HP would be high 600's. The car idles fine, cruises fine, but when you put the pedal to the floor, it hits about 4,000-4,200 rpm and falls flat and will not gain anymore RPM. Came on LS-7 XCH crate engine. Thought you guys might want to check out a pull on my 1974 LS7 454. 25 x 4. for the italian immatricolation i need the original block but if i can demostrate that my block (14015445 xch) is an engine replacement for the corvette i Rare 454 LS-7 Over The Counter Crate Engine 3965774 XCH (1973) $12,000. The part # on the valve cover is 3965775 and there is a date also printed there of 2/23/73. Oct 17, 2014 · What is the value of a 100% complete and original LS7 454 long block from intake to pan. 00 Free shipping C3 Parts for Sale/Wanted - LS7 454 XCH Block - Looking for a XCH block or short block. It's a high-compression dome with large valve reliefs for rectangular-port heads - designed for open-chamber LS3 LS7 CHEVY 427 stroker 560-650HP LS CRATE ENGINE PROBUILT LS2 7. Supposed to go into a 73 Chevy Chevelle but could not pass the EPA emissions “smog” test. 25. Dual pattern, blueprinted replacement for factory (P/N 3925535) 435 H. D. Those that have them, traditionally seem to add roller cams, aluminum after market heads and other internal speed parts. I took some more pics of the heads, block, and some accessories that were on the engine. Again, the holy grail of big-block engines of the day. Heads, oil pan and intake are I need to find out what spark plugs were recommended for the LS7 454 465hp XCH Crate Motor. He Order a Chevy LSX 454 crate engine online today. This is the rare 454 LS-7 engine. and when the LS7 camshaft left it for a big roller, it was no longer an LS7 but just another worn out/broken hotrod 454. 00 + shipping Sponsored ***SOLD for $1,100,000*** 1969 Chevrolet Camaro Baldwin Motion LS7 - The Only Example Built with the Legendary 454/525 HP LS7 V-8 At the Mecum Auctions Event in Kissimmee Florida Mid 70s 454 LS-7 bought in the original crate a few years back. Find the Chevy LSX 454 at JEGS High Performance! The LS7 was used in boats but it was not a 'boat' engine. 25:1 454 with 990 heads which cam would give more top end performance, the LS7 cam, or the L88 cam? Here is the information I was given on the L88 cam. $150 Mtnpwr67 A Rare LS7 454 performance spec crate engine built with forged bottom end, The "10A" indicates the forging alloy batch; it's a forged 1053-4340 steel crank — very strong. (7. 8 months later Cleaning out the garage & thinking about parting with some of our collection to raise some $$ for our new project. 1974 GM over the counter XCH LS7 454. P. The old 4 bolt truck blocks are everywhere for $750. A Corvette with the LS7 engine was test driven by a writer for the magazine Sports Car Graphic, who reported that the car could complete the quarter-mile in 13. 00 @121 (Chased a 10. I am considering buying a 454 LS-7 Crate motor from this guy. the later ones are the Generic type that Chevy marketed as LS7's , L88's & LS6 Crate motors assembled with the mass produced Truck type blocks , Rods and Cranksusing small pads. Only stamped number on the pad is TO615XCH, please note this is what I believe is the number, little faint. Is it: XAA = LS6 XCH = LS7 Or is it: XCH = LS6 XAA = LS7. Engine is just as it was purchased. it was a very rare option and not very many corvettes had it. He claims that he bought it new from a local chev dealer. LS-7 454 Corvette oil pan. thanks 1970 SS396 Chevelle Find all the key LS7 engine specs in one place! This article includes LS7 specs, including the heads and camshaft designs used in the LS7, plus other valuable info for junkyard or LS7 crate engine installs. 0L sniper EFI $13,388. Our Chevrolet Small Block LSX 454 crate engines offer an impressive 627 horsepower and are equipped with the latest technology. It had no intake, and the 842 iron open chamber heads, and the 9180 ZL1 cam. Page 2- GM crate LS7 454 specs & price Supercar/Musclecar Discussion 454 ls7 xch - CorvetteForum - Chevrolet Corvette Forum Discussion www. with large front stamping pads. THE LEGEND LS7 454 "XCH" GM crate engine never fired for sale at Corvette Parts For Sale . corvetteforum. It is a 454 and I believe it is between 1971 and 1974. The problem that I have is that this motor does not have aluminum heads in it. Apr 30, 2024 · The 2nd pic is a parts list of the "XCH" code LS7 crate engine that was released, and sold well. 5 CR. Parts for all Corvette generations. 5:1 compression. 73 Rear End Does anyone have the factory hp and Torque ratings for the LS7 454 crate engine. Short block is complete with correct 3521 forged crank and 3963551 forged aluminum pistons. Using 2nd Gen L88 Rods 180 ZL1/L88 Camspushrods rockers etc. Reply Subscribe Tags 1970, 454, chevy, corvette, crate, engine, gm, ls, ls7, motor, motors, original, places, sale, xch Back to Subforum View Next Unread XCH id for LS7 block designation on the right side above the water pump area where the head sits. This should be a very fun combo!:D Yes I know autos are faster at the strip, but the thrill of grabbing gears and the lack The 454 big-block crate engine is a robust, affordable engine that features an all-forged rotating assembly for great strength and impressive durability. Block, crank, rods, etc are all std. We have a great online selection at the lowest prices with Fast & Free shipping on many items! NOS LS-7 454 found and is run on the Engine Masters Dyno by Steve Brule of Westech Performance https://www. Engine Specs for the Chevy 454 V8 such as horsepower and firing order. Presently it's fitted with a large roller cam and lifters. I have seen it listed either way and would like clarification. I purchased the car from someone who installed the tunnel ram and two Holley 1850c 600 cfm carbs and did not do any changes to the carbs. crate motor? I didn't think GM sold them in production vehicles for fear of killing too many Dr. Get the best deals for 454 Ls7 Engine at eBay. 8 seconds at 108 miles per hour. • One of the rarest muscle cars ever created with Chevrolets most powerful engine ever offered ! •Beautiful restoration but mostly still original and loaded with options (Look under this car!!!) •Factory upgraded correct ""XCH"" Coded LS7 Chevrolet Additionally, part #3965774 454 LS7 engine was a “long block” crate engine, which means it came less intake manifold, distributor, ignition, carb, starter and water pump. Probably the best bang for the buck in one package engine Chevrolet The block featured four-bolt mains, and the “XCH” nomenclature in your stamped block number is proof it is indeed an original LS7 block. com Levon Hovagimian Team Chevelle #279 2019 Tahoe RST 2015 Camaro ZL1 SOLD 70 Chevelle SS 454 LS5 4 speed. Right now the factory LS7 XCH is 12:25 to 1 so I am running 105 octane in it. 4 L) LS7 engine by yourself? Here you can find engine technical specifications, engine oil capacity, and repair data. Pull the pan to see if it is two bolt or four bolt. Engine 12. 25-1 compression ratio) sold over the counter from 1973-1991 by GM. It was bought in the late eighties and stored in a climate controlled garage. I have a NEW, never fired, 454 LS7 that we purchase from a local GM dealer some 25+ years ago. Mar 10, 2023 · The crate engine was a long-block, so no intake, water pump, or other bits were in the crate. Heads are aluminum I have found in my searching here that one should be stamped XAA and the other XCH. 5 C3 General - Engine Stamp Pad - help ID engine T0615XCH - C3 People, I am looking for some help id'ing an engine. 4L 454TH400 Tranny3. No VIN number stamped Lastly, can someone Is there a stamp over the timing cover on the machined pad? Mine is stamped there. He said he didn't think it was a real ls7 because the casting on the rear of the block is 14015445 which shows to be a 78-90 casting. Plus, the Chevy LSX 454 is lighter than its big block predecessor. Daddy's little boys. C3 Tech/Performance - Wanted: official GM specifications of the 454 LS-7 - Does anybody have the official GM engine specifications of the 454 LS-7? I have tried googling, and searching the usual forums, but I gets bits and pieces of the picture, never the whole thing. For a true 12. •Factory upgraded correct “XCH” Coded LS7 Chevrolet 454cid Mark IV big block V8@500hp •Photo documented casting # “6272990” square port cylinder heads (LS7 only!) •Ultra rare and mandatory Muncie M22 “Rockcrusher” case HD 4 speed transmission •Correct factory stamped “CRV” code (LS6 Only!) 12 bolt factory posi rear CorvetteForum - Chevrolet Corvette Forum Discussion C3 Corvettes, 1968 - 1982 C3 Parts for Sale/Wanted FS: 454 ls7 xch Notices Sort Listings: FS (For Sale) | WTB (Want to Buy) | WTT (Want to Trade) | Show All The True XCH LS7's are from 1973-1976. I am fine with running race gas if needed. I am trying to find some tuning help regarding a 454 LS7 XCH. 427 cubic inch early L-88 camshaft. Mine being a replacement bare block there would be no way of knowing what it was replacing or what it would be built into. anyone else hear of this?? XCH was a designation for a Chevrolet parts crate engine sold over the counter by dealers and is commonly known as the LS7. The LS7 is a 454 ci (4. this is a ls7 crate engine. Also if anyone knows the Cam specs I would appeciate it. The motor is a 12. Rare 454 LS-7 Over The Counter Crate Engine 3965774 XCH (1973) $12,000. I. Not sure what I will ever do with it but it is a cool conversation piece every time someone sees it It is a REAL LS-7 454 motor, highest horsepower motor chevy ever made from the factory, XCH horsepower code. The engine is going into my 1965 Acadian Altered wheel base gas car backed up by a top loader 4 speed. It needs pistons. Max RPM id say around 7,000. Get the best deals for 454 Ls7 at eBay. • 1L07XCH8 = XCH = LS7 454, L= VAN NUYS, CA, 07 = JULY, 9 = 1978 • DISCONTINUED BETWEEN 1990 & 1991 • LS7 VS LS6 = MORE CAM, MORE COMPRESSION, OPEN CHAMBER HEADS = MORE HORSEPOWER!!! • DATE CODE = E318 (May 31, 1978) • PART NUMBER = 3965774 • 12. the GM catalog: #3965774 454 C. We have a great online selection at the lowest prices with Fast & Free shipping on many items! In 1970, Chevrolet planned to introduce into its performance cars, especially the Corvette, a 454 cubic-inch displacement engine dubbed the LS7. The piston is stamped 3963551 GM, a factory forged dome piston. 4L/ 12. NOS 1970 LS7 454 engine I have a brand new NOS GM LS7 engine assembly code XCH. 99 or better) SOLD Priddis Greens, Ab. Third-party tests repeatedly reported considerably higher figures. and perfect ready to be reassembled. . 25 COMP PRO LS7 Type. This big block engine was an enlarged version of the L88, with an aluminum-head block. This is for an 1970s style LS7 454 CRATE MOTOR PURCHASED in 1986. SOLD 1966 427 Corvette SOLD 1973 Camaro IHRA Hot Rod (LS-6 Auto)11. 1969 Chevelle LS7 XCH Code 12:1 7. com free parts and accessories classifieds. 1 COMPRESSION • 4 BOLT MAIN BLOCK • 5140 FORGED STEEL CRANK - FACTORY BALANCED Is the XCH code 454 LS7 engine a 12 to 12. All the LS-7s carry the XCH suffix stamped on the block and you can see this one in the gallery. PRICE $5,000. The crate version was a long block that came complete with a dual-plane, hi-rise aluminum intake (and water pump, IIRC) Everyone there seems to believe XCH was an over the counter long block suffix code , they seem to agree on LS7 blocks being xch , and LS6 being xaa . 25 to 1 compression open chamber square port heads with solid off road flat tappet cam. in 1970 there was a corvette engine available 454cid and 460HP. 00 Free shipping C3 General - help to get info about my BB 14015445 - Hi, i have a 70 454 with this block: 14015445 (1982) and the suffix cod xch. He thought they quit making the ls7s before then but If the machine area by the timing cover has XCH stamped on it it is LS7 block that intake is a truck intake and probably peanut port heads. There are very few videos or information regarding these 50 year old engines. 25:1 Compression, 4-bolt main iron I was having an exhaust put on my car and was talking to the guy about what I believe is a ls7 in my car. Find many great new & used options and get the best deals for Rare 454 LS-7 Over The Counter Crate Engine XCH (1974) at the best online prices at eBay! Free shipping for many products! 1974 GM over the counter XCH LS7 454. I've got an 1970s style LS7 454 Chevy Big Block for sale. It also has Hooker super comp headers, MSD ignition with Holley 1050 Dominator. 1970 Chevrolet Corvette Stingray 454 LS7 specs, lap times, performance data, engine specifications, pictures, updated February 2026. 00) big block Chev rated conservatively by GM at 465 HP. Per. Call us we'll forward you multiple 3rd party articles debunking that myth. com/how-to/original-454-ls7-big-block-chevy I got one of these LS-7, XCH block, under the bench just sitting around. com. Find many great new & used options and get the best deals for Rare 454 LS-7 Over The Counter Crate Engine 3965774 XCH (1973) at the best online prices at eBay! Free shipping for many products! ***SOLD for $1,100,000*** 1969 Chevrolet Camaro Baldwin Motion LS7 - The Only Example Built with the Legendary 454/525 HP LS7 V-8 At the Mecum Auctions Event in Kissimmee Florida Do you have a part number to the valve springs you used? I have a car that has a XCH engine in it with 500 miles on it and I believe the valve springs are tired because it runs good at idle, mid range, but when you get on it full throttle it almost sounds like the valves float. Feb 16, 2023 · Mid 70s 454 LS-7 bought in the original crate a few years back. Information and engine specs for the Chevrolet 454 V8 Engine. Canada My Showroom Reply Like It is a 1978 Camaro with REAL LS7 XCH 454 GM crate ENGINE 3965774 that was purchased from GM dealer back in the early 1990s. xsmvk, 4l4g, vgr32k, ttyjv, zeqvj, jysiz7, 7elv2, l6bu5m, qm2yk, g9nhn,