1970 LT1 370hp engine value?
Thread Starter
6th Gear
Joined: Jun 2012
Posts: 6
Likes: 0
"....and by the OP's posts, doesn't know what or if he has anything."
Finding out what I have is the purpose of the post.
I removed paint from the machined pad in front of the passenger cylinder head and did not find any numbers. Does that mean the block was machined again after it left the factory? My understanding is that this was a 1970's engine swap exchanging a destroyed supercharged Studebaker 289 with a good 350. On my next visit to the car (which is in storage on the other side of town) I will remove the valve cover and check the numbers on the head.
I have a friend who is a Corvette enthusiast with a mid 70's Vette equipped with nitrous coming back to town this weekend. I will ask him to take a look at the vehicle and see what insight he has to share.
If I do sell the engine and keep the car I would not put an original engine back in it. When I purchased the car I was told its engine was in upstate New York. When time and money permitted I would power it with a more modern I.C. engine or go electric. I have not seen an electric Avanti yet.
Thanks again for the input.
Finding out what I have is the purpose of the post.
I removed paint from the machined pad in front of the passenger cylinder head and did not find any numbers. Does that mean the block was machined again after it left the factory? My understanding is that this was a 1970's engine swap exchanging a destroyed supercharged Studebaker 289 with a good 350. On my next visit to the car (which is in storage on the other side of town) I will remove the valve cover and check the numbers on the head.
I have a friend who is a Corvette enthusiast with a mid 70's Vette equipped with nitrous coming back to town this weekend. I will ask him to take a look at the vehicle and see what insight he has to share.
If I do sell the engine and keep the car I would not put an original engine back in it. When I purchased the car I was told its engine was in upstate New York. When time and money permitted I would power it with a more modern I.C. engine or go electric. I have not seen an electric Avanti yet.
Thanks again for the input.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
That's exactly what it means. The operation is called 'decking the block' and unfortunately removes all identification as to what specification the engine was originally built to.
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
On my next visit to the car (which is in storage on the other side of town) I will remove the valve cover and check the numbers on the head.
While this won't tell you what the engine is it will at least help to see if the heads are 70 LT-1. You may know this but in case you don't have it -the cast number should be 3927186 with a date code before August of 70 (July was the last build dates for 70) they will have screw in studs and should have guide plates although those are often missing. You shouldn't have to pull the cover but just look through the hole in the top.
The other higher $ parts to easily check will be the ignition system as it should be a TI system with the amp and right coil and the alternator with a 1100884 case. You may take a quick look at the oil pan as well as the early 70 6 quart are worth a few bucks. It will have a longer bottom then the later ones and those used with power steering.
While this won't tell you what the engine is it will at least help to see if the heads are 70 LT-1. You may know this but in case you don't have it -the cast number should be 3927186 with a date code before August of 70 (July was the last build dates for 70) they will have screw in studs and should have guide plates although those are often missing. You shouldn't have to pull the cover but just look through the hole in the top.
The other higher $ parts to easily check will be the ignition system as it should be a TI system with the amp and right coil and the alternator with a 1100884 case. You may take a quick look at the oil pan as well as the early 70 6 quart are worth a few bucks. It will have a longer bottom then the later ones and those used with power steering.
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
a 3927186 head still may or may not be a LT1. it was also used as a base engine head in 70 also for passenger cars, camaro, nova and chevelles, also with corvettes. depends on the valve size, if you have 2.02/1.60 valves, then yes.. an overwhelming number of these heads were used for non LT1 cars.
so far I see no evidence this is a LT1 in all these posts.
so far I see no evidence this is a LT1 in all these posts.
Thread Starter
6th Gear
Joined: Jun 2012
Posts: 6
Likes: 0
On what other cars was the Holley 780 List 4555 used? nastyz28 lists that carb for the manual transmission 1970 z28 only for the 1970-72 LT-1.
I am selling the car locally.
From replies on this forum, a 1970 LT-1 is not that valuable to justify removing it from the car. If a local is interested in the engine they should be able to verify whether or not it is actually a 1970 LT-1.
I am selling the car locally.
From replies on this forum, a 1970 LT-1 is not that valuable to justify removing it from the car. If a local is interested in the engine they should be able to verify whether or not it is actually a 1970 LT-1.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Not sure how you can say you are being told a 70 LT-1 engine isn't valuable? I am making a statement/offer that if you have a real and complete 70 LT-1 in good condition it is worth a minimum of $4k to me and if it was rebuilt with original parts it could be double that. I have around $9k in my 70 LT-1 build and I am not done.
You want $12.5k for your entire car so how is this not valuable? My low offer is a third of your entire asking price.
What you have sounds like a few parts that were, or could have been, used on an LT-1. I have asked a few times if you have certain parts and I have not seen those so at this point I would be hard pressed to say you have even an incomplete 70 LT-1.
You want $12.5k for your entire car so how is this not valuable? My low offer is a third of your entire asking price.
What you have sounds like a few parts that were, or could have been, used on an LT-1. I have asked a few times if you have certain parts and I have not seen those so at this point I would be hard pressed to say you have even an incomplete 70 LT-1.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
Instructor
Joined: Jul 2019
Posts: 122
Likes: 74
From: Sacramento, California
I am just finishing up building a 70 LT-1 engine and have spent some time looking for real LT-1 parts. To my knowledge there are no parts that are unique to the LT-1. There may be a code difference on say the distributor but all of the parts appear on something else so the date codes and numbers become very important to someone doing this kind of rebuild. The parts you have mentioned so far are not the hard to find big dollar parts. The exhaust and valve covers mentioned are many times aftermarket and are on many different cars. The carb - if all of the numbers and date code are correct is worth a couple hundred if it needs to be refreshed, you can get them all done for the $500-$700 range.
The parts I would pay more money for over another sbc part are - ignition system including dist, coil and amp, the right numbered alternator is fairly valuable, heads if they are real LT-1 with a 70 date code, the right coded intake (not the aftermarket many think is an LT-1) the proper coded crank (if it has never been ground) a good set of original rods and pistons - good meaning slightly or never used.
I have a 70 LT-1 car so it has been a fun and worthwhile project for me but I can't see why anyone would ever go to the trouble and the expense if they didn't have the right car to put it into. You can build a much better engine for less money so your market is fairly limited. A real LT-1 complete engine with 100% of the right original parts that needed a rebuild would be worth around $3k-$4k to someone that needed it. If you have any of the hard to get items and they are 70 LT-1 I would be interested in them that way you could keep the base motor and switch out certain parts but it probably wouldn't be worth the trouble.
The parts I would pay more money for over another sbc part are - ignition system including dist, coil and amp, the right numbered alternator is fairly valuable, heads if they are real LT-1 with a 70 date code, the right coded intake (not the aftermarket many think is an LT-1) the proper coded crank (if it has never been ground) a good set of original rods and pistons - good meaning slightly or never used.
I have a 70 LT-1 car so it has been a fun and worthwhile project for me but I can't see why anyone would ever go to the trouble and the expense if they didn't have the right car to put it into. You can build a much better engine for less money so your market is fairly limited. A real LT-1 complete engine with 100% of the right original parts that needed a rebuild would be worth around $3k-$4k to someone that needed it. If you have any of the hard to get items and they are 70 LT-1 I would be interested in them that way you could keep the base motor and switch out certain parts but it probably wouldn't be worth the trouble.
The LT1 is a weekly driver and runs great. I know it has been detuned somewhere along the line as it runs on regular gas, never pings. Probubly those 71 heads. It doesn't mater to me if my car is all original or not. What maters to me is, I like it, it's fun, runs great, and looks greater. Body and interior are pure. I show it with the hood closed so all the hamburgers cannot point and say, well lookie here, thats not the original engine.! Beside all that, I cannot afford a numbers matching car.
This is a great forum for Corvette fans and a world on knowlege resides here.
Dale
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
It is so easy to build a 425hp 350 now that the mighty LT-1 is not worth it any more except for the short block and intake/carb......the heads are so bad that the intake will support another 100 hp than what the LT-1 was rated........even if I had an original LT-1 car.....I would almost certainly put heads on it and headers to compliment the intake......
A great conversation piece but scrap the cylinder heads........Trick Flow even makes a bad *** head with Camel Humps cast in it because I am not the only person who thinks this way.......
A set of heads on a stock LT-1 with no other changes would be worth 60 horsepower or more.......with headers 75 or better.......
With a modern pair of heads/valvetrain......you essentially have a nice track motor as the rest of it was pretty dam good.
Note: The intake is so good that I have considered a ported Winters intake with milled divider for my sneaky 406......to replace the Team-G......I do not think it would hurt that much.....the 406 makes 500hp.
Jebby
A great conversation piece but scrap the cylinder heads........Trick Flow even makes a bad *** head with Camel Humps cast in it because I am not the only person who thinks this way.......
A set of heads on a stock LT-1 with no other changes would be worth 60 horsepower or more.......with headers 75 or better.......
With a modern pair of heads/valvetrain......you essentially have a nice track motor as the rest of it was pretty dam good.
Note: The intake is so good that I have considered a ported Winters intake with milled divider for my sneaky 406......to replace the Team-G......I do not think it would hurt that much.....the 406 makes 500hp.
Jebby
Drifting
Joined: Nov 2013
Posts: 1,806
Likes: 258
From: Dublin Ohio
Dale S you've resurrected a 7 year old post (as your first post)🙂
Not saying it's illegal or anything but if you have something to say you may want to start a new thread.
I still don't know how this happens so often but then again I only use the app so I only see recent posts.
Not saying it's illegal or anything but if you have something to say you may want to start a new thread.
I still don't know how this happens so often but then again I only use the app so I only see recent posts.