riverdogs00 Posted February 16 Share Posted February 16 Mid 70s 454 LS-7 bought in the original crate a few years back. There are very few videos or information regarding these 50 year old engines. Those that have them, traditionally seem to add roller cams, aluminum after market heads and other internal speed parts. This engine was the successor to the LS-6 found in Chevelle's and Corvettes, and was slated to go into the Corvette. GM killed it due to emissions regulations. Subsequently, these were sold over the parts counter as a Off highway use only engine. GM rated the LS-6 at 450 HP, and the LS-7 at 465. The engine was only offered as a long block, no manifolds, carbs, distributor. This particular engine was located in 2020 still in the factory crate. It was purchased and shipped directly to my engine builder in las Vegas where it was disassembled, cleaned, and checked. We only replaced the following parts as a precaution, and maintained stock level parts for a true representation. Gaskets, rod and main bearings, Valve springs and seals, and rings. The engine received a light hone, but maintains its standard bore, and a light valve job as the valves were exposed for 50 plus years. This engine uses the same solid flat tappet cam as the 427 ZL-1, and was a step above what the 427 L88 had in terms of lift and duration. Parts added to this specific build to complete it were twin Holley 660 center squinters, Offenhauser tunnel ram, MSD E curve distributor, poly locks for the stock rocker arms, and the Edelbrock valve covers. Rated at 465 HP, this engine made 582 hp at 6000 rpm with no air cleaners, and 2 1/4" dyno headers. Installing my 1 7/8 American racing chassis headers (1970 Monte Carlo), and twin velocity stack air cleaners brought the power down to 570 at 6000 rpm. While I realize that this engine was never offered in a passenger car, its unique enough for those that are interested in the Big Block Chevy. Link to the video can be found here: 8 Quote Link to comment Share on other sites More sharing options...
Montemedic Posted February 16 Share Posted February 16 Very nice build. What are your plans for it? Can you post the dyno sheet with the hp and torque numbers? 1 Quote Link to comment Share on other sites More sharing options...
jft69z Posted February 16 Share Posted February 16 Looks good, thanks for sharing the info! I bought 2 of the crate LS-6, part# 366250 engines back in the day. One is in my current '72 Custom, the other highly modified one now lives in my 69 Z/28. 6 Quote Link to comment Share on other sites More sharing options...
LS65Speed Posted February 16 Share Posted February 16 Did the same thing back in the day! Not in a Custom however. Currently runs a 67 Vette Rect. port 3x2, Edelbrock 110 CC oval port heads and a 5 Speed Stick among other mods. Got some pics of the engine and the car? Love to see any pics you have. Quote Link to comment Share on other sites More sharing options...
jft69z Posted February 16 Share Posted February 16 36 minutes ago, LS65Speed said: Got some pics of the engine and the car? Love to see any pics you have. Both cars are in this thread. Lot of pics, and a lot of side tracking, but that tends to happen here a lot. I have a bunch of actual photographs of the engines as they came from the crate (back in the late 80's, complete with the black paint, 'Special Parts Notice' sticker on the valve cover, the XAA engine code, and the installations. I haven't converted those pics to digital yet, on the long list of things to do before I die. https://www.firstgenmc.com/forums/index.php?/topic/19368-new-guy-here/#comments 3 Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted February 16 Author Share Posted February 16 2 hours ago, Montemedic said: Very nice build. What are your plans for it? Can you post the dyno sheet with the hp and torque numbers? Yup, I will. He printed a couple of the pulls, then just gave me a thumb drive with all of them, but my pc didn't like 1 of the files and deleted it. Now I cant view any of them. I will take a picture of 1 and load it Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted February 16 Author Share Posted February 16 6 minutes ago, riverdogs00 said: Yup, I will. He printed a couple of the pulls, then just gave me a thumb drive with all of them, but my pc didn't like 1 of the files and deleted it. Now I cant view any of them. I will take a picture of 1 and load it 4 Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted February 16 Author Share Posted February 16 Funny thing on the ARH headers. We finished the day, and I wanted to run the engine with the air filters and headers I was going to run in the car. lost 12 HP at 6000 rpm total, and the headers turned gold ha Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted February 17 Author Share Posted February 17 20 hours ago, Montemedic said: Very nice build. What are your plans for it? Can you post the dyno sheet with the hp and torque numbers? Good morning - I missed this question, and still am learning the nuances of posting and replying - I've primarily just lurked in the past. The engine was the primary focus on this build. I've been looking for one since I fist read about it in a parts magazine in 81' (same year as I saw a picture of the SS 454 monte carlo and knew I would have one some day). I just love old factory muscle (all brands), all of the advertising and claims that went with them, and the whole vibe of that scene. The cammers, super dutys and ram airs, the ardun conversions for the flat heads, etc... Once the engine was acquired, then the search for the right vehicle to put it into went into motion. What I really wanted was kind of a day 2 look. I wanted original paint and interior, and for the car to look like someone had bought a car new, and swapped engines the same year. Tasteful, period correct mods, manual trans, etc. After looking daily for 18 months nation wide, I just was beginning to realize I could not afford what I wanted, and low and behold this 1970 car came up for sale 2 miles from the house. Its been repainted, but is severely faded, and pretty straight and original. It was a 350/250hp / turbo 350 / 10 bot car. Engine and trans out of it, and the guy was doing an LS swap. He wanted 8k. I bought it for 6k, and let him keep the LS, but I took the original drivetrain. Sold the entire drive train to a buddy that's looking for the right body. I decided to go with a 9" rear vs the 12 bolt simply out of cost, and ease of gear changes down the road. Its the only main deviation from the original plan. Its a Quick performance unit with 4.11's, trutrac, 35 spline axles, 1350 yoke and upgraded center section. Disc brakes were added when it became apparent that the drums they provided would have necessitated cutting off brackets and rewelding...then it would have to be re powder coated (well it should anyway). I've replaced the passenger floor pan, replaced all of the body bushings, converted to manual brakes (did not want to run a vacuum pump or reservoir), new wheels and tires, built all new brake lines, removed the AC, converted the pedal assemblies to manual, and am presently going through the column replacing the ignition switch/turn signal switch, etc... I'm maintaining the original interior (cloth bench). Yhe front will have a blanket on it due to wear and deterioration, the rear looks great, just faded. Carpet is waiting to go in, once I get the tunnel cut and hump installed. The transmission is a M23. its an upgraded version of the original M22 purchased through https://midwestmuncie.com/ . presently I am still waiting on this unit, having ordered it in November. They are waiting on the main case from https://www.autogear.net/motorsports/ . The engine is dyno'd and tuned. and ready to drop in, now that I finally have the headers as well. Hopefully the engine will go in, in the next week or 3. the car is just going to be a fun weekend burnout toy, and romp around machine. It runs off of $10/gallon 100 octane I can get at the pump here, so its no highway cruiser. My blue SS454 car is my other weekend cruiser, so will be fun to change it up. Thats where Im at. 7 Quote Link to comment Share on other sites More sharing options...
Montemedic Posted February 17 Share Posted February 17 Nice to have 2 Monte’s and options … Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted February 17 Author Share Posted February 17 14 minutes ago, Montemedic said: Nice to have 2 Monte’s and options … That it is. Quote Link to comment Share on other sites More sharing options...
Tmac Posted February 22 Share Posted February 22 Thanks for sharing this! 2 Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted February 22 Author Share Posted February 22 12 hours ago, Tmac said: Thanks for sharing this! Happy to. I've actually had this very post/idea in my head for the past 10 years, simply because there is nothing out there on some of these old Factory engines. everyone modifies them, and then, well, its not original anymore. 1 Quote Link to comment Share on other sites More sharing options...
TheBMan Posted February 26 Share Posted February 26 This is super cool! I mean, look at the "heavy duty parts list". It gives you the part numbers if you wanted to build your own! Assuming you could get those parts, of course. 1 Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted March 11 Author Share Posted March 11 Group, The motor trend article came out for this engine. I wish they would have contacted me first, as I found 2 errors, but the meat of it is there. There was not 6 qts of oil put in it, and GM never rated it at 522 HP. It was factory rated at 465. https://www.motortrend.com/how-to/original-454-ls7-big-block-chevy-crate-engine-dyno-westech/ 3 Quote Link to comment Share on other sites More sharing options...
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