I have purchased a 1970 LT1 built on February 11th 1970, which has been stored for a long time. The last owner had plans to restore and began taking it apart. So the interior was full of parts just piled on each other. The Engine compartment is partially dismantled and the interior is almost fully dismantled.

I'm still discovering the details of what I have, but I will likely need help putting it back together. Mainly in the form of pictures of selected areas...just so that I know how it should look. I'm familiar with C2s and C3s, having owned before.

I was hoping to tap a pool of 70 LT1 owners which I could seek help from. If you have a 70 LT1, please chime in.

It has headers so I will need to eventually find the correct exhaust manifolds for it. The castings are Left: 3872765, Right:3932461
However, I have seen a lot off variation with the same numbers. So I think I need to understand what they should look like for 1970, and specifically the date codes. If you have pictures of your manifolds, please post.

Thanks,

 

I also started this thread on a mystery discovered: https://www.corvetteforum.com/forums...and-a-i-r.html

 

Nice find. Looks solid. Is it indeed and LT1? Have you checked the numbers etc?
I'll take those slot mags if you give them away!!!

 

• It has the right hood, not a converted big block hood
• Transistor ignition
• It has the right heads, with valve guides
• I scoped the pistons and they are domed
• It has the right aluminum intake manifold
• The water pump pulley is correct for LT1
• Holley carb and associated
• 6500 RPM red line tach
• It appears to have the original radiator...don't know if its the larger LT-1 or not. How can I tell?

The build sheet on the tank is mostly missing, all the options info is lost
Unfortunately, the engine is not the original. It appears to be a warranty replacement



The mags have a polarized response, people love them or hate them. The fronts look okay, but the backs stick out too far

 

I just love the old school '70's look they provide. Grew up seeing those all over the place on a bunch of muscle cars in the day.

 

Looks like a very nice start indeed. Congratulations on your new toy/Project!

 

Let me know if I can help in anyway
Bullshark

70 LT1. JANUARY 22 BUILD

 

When I was younger I disliked Silver. In fact my 63 which is still a restore in process after 2 decades, was originally silver and I was always going to change the color to yellow. Now that I'm older, I will keep the original silver and really like the silver and black contrast. Your vette looks great.

Did you see the request above for pictures of exhaust manifolds?

 

Congratulations on a Nice find!

Here is a list of LT-1 features from this forum and elsewhere that might be helpful.

Check your 70 AIM, but I believe the 70 LT-1 radiator was the 26" core for a 350 w/ac or the LT-1.


Updated 10-23-2020 Here is a great list I saved from a posting here:

There are a few things that only a LT-1 would have , some are pretty easy to change out and some are not very easy at all.in no particular order.

1st. No 1970 or 1971 LT-1 had A/C

2nd. Emission sticker on fire wall behind master cylinder should have letters AX on upper left corner for a 71.

3rd. All LT-1's are 4 speeds. (M20 was std , M21/M22 were optional)

4th. Tach has 6,500 RPM red line on 1970 & 1971 and on 72's w/o AC

5th. All 71 LT-1's came with A.I.R. system. If removed should still have manifolds with holes for the tubes, Car may have headers and if so ask to see old manifolds.

6th. LT-1's had copper radiator W/O a overflow canisiter on the passanger side fenderwell. There should also be no holes where one had been mounted.


7th. All 70 / 71 LT-1's had Transitor Ign. system. That may have been removed. But if it is removed look for the 3 holes on the front face of the driver side inner fender well where the Amplifer box was mounter.

Take a flashlight and look in front of the front wheel or open hood and look at it from the front side. 2 holes on bottom and 1 on top. No TI on the 72 LT-1


8th. Should have a Winters snowflake intake manifold with casting # 3959594
for 1971 and 1972, per NCRS, 1970 should be #3972110. Both manifolds are aluminum (my addition).


9th. LT-1's had a Holley carb. so there is only 1 fuel line , no return line like a quadra-jet carb. Look along frame rail on passanger side for the single line. Also the fuel tank is different. There should be no nipple on the passanger side, side wall for a return line.

If you lay on your back under the rear wheel you can reach your hand up and feel for an indention on the passanger side. If there is a nipple that is capped off , then beware.

Also the single fuel line on a LT-1 was not the same line that was used to feed fuel on the 2 line set up. So if someone removed the return line the look of the 3/8 line is still different. Not a big difference but if you can look at a car with a 2 line set up then you can see what you do not want to find.

10th. LT-1's had solid lifters , but if the car does not then that is not to big a red flag. Many people do not like them and may have replaced with HYD. lifters during a rebuild.


11th. The hardest to fake and most expensive would be the 4 bolt main block. No # on the outside of the block can verify this.

Only way to verify is to remove the pan or have a lighted optical viewer and remove the drain plug.


12th. LT-1's use 2.5" exhaust pipes like the big block cars. But the manifolds were still 2" set up. So the pipes flair from 2 to 2.5" about 6 inches from the manifold. The exhaust hangar at the trans is also different. Look online at the Corvette Central site and you can see both 2" and 2.5" hangars.

13th. As I recall the highest rear end gear was 3:36 if trans was a M20

And id Trans was a M21 or M22 the 3:55 was highest gear

M20 3:36 Economy

3:55 Standard

3:70 Performance


M21 / M22

3:55 Economy

3:70 Standard

4:11 Performance

14th. The 71 /72 LT-1 Aluminum valve covers should have a rubber oil cap not a twist in. These covers are very hard to find. All the catalog’s sell the twist in cap style.
70 LT-1 has the regular slotted twist in oil cap

15th. LT-1's have the same heavy duty half shaft retainers as big block cars. Look at the rear end side yokes, there should be caps with bolts. Base cars used U bolts with nuts.

16th. The rocker arms have a letter O stamped in them.

17th. The balancer on the crankshaft is an 8" unit not a 6"

18th. Original LT-1 hood would not have the holes for 454 number emblems since LT-1 decal and stencil was used.

That is all I know of. and you could not fake all of this and sell a car for a mid 20's price and be worth the effort / expense.

So until someone finds the lost records from St Louis anyone buying a no base model car will be going out on a limb at little unless you are buying from the original owner.

19th You could add No p/s in 1970 with a CTU engine. CTU had the 6 qt. oil pan. 72 and 71 (later 71?) had the regular 5 qt oil pan. Also, plastic fan shrouds on LT1s. 10-23-20


20th. Lots of places to find this (the key is of course: is it an original stamp?)
1970 CTK, CTR, CTU CTV(ZR1)
1971 CGY(ZR1), CGZ
1972 CKY CKZ(ZR1) CRS CRT

 

Boy that stamp pad looks familiar. Numbers so close they could have shared a shelf some where! I have not run across any other examples/explanation with 3 letters in a row vs the CE followed by a number than a letter etc.
Looks like a great find. More pix when you get them!

 

Your engine block is a service replacement block indicated by the CE. There are a lot of theories as to the "B" 1. being shift 2. A bare block etc. The 12770 would be 12770 service block produced at Flint. Find the casting date for the block will find out when it was produced.

From your other post the Radiator does appear to be original Metal tag MK9 and the overflow hose clip is still present.

 

A number of web sites reference Flint and Tonawanda CE stamped engines. The references would have both the engines pictured here be inline 6's produced at Flint by the serial number range (CEB12770, CEB1373) which they clearly are not?

 

Then the first digit 1 is most likely 1971 and 27706 is the sequence number.

 

Everything checks out except:
2. Emission sticker on wall behind Brake master. The left corner is missing. However on the right I see a number "3989299" and below it is "CL" in bold. Here it is here: https://www.classicindustries.com/pr...rts/dc448.html It does show 370HP

5. The A.I.R. system is gone. Headers in place.

9. The tank is full of holes, but original, as it has the stamped "OLA" logo. It does have a vent with a special ball valve assembly attached. Its for the EEC system. This site says its correct: https://www.gastanks.com/1970-1972-w...info/GM%2D33F/

10 & 11. Unknown
12. Exhaust not original
15. Half shafts, see picture below. Is this what you mean or do you mean the outer joint?

 

I wouldn't lose any sleep on the originality of that block. GM used a lot of replacement blocks back then. Guys bought these cars to run hard. Bring that baby back to life and enjoy it!

 

In the end, it is what it is. My guess is there was a warranty replacement in 1971. They put in a new short block, and transferred everything else from the original. The only way to know is talk to the original owner... who I'm speculating is no longer living.
The amazing thing is this vette only has 70K miles. Everything is original, Brake master cylinder, ball joints, fuel pump, etc,

My understanding is that it was left in a field for 5 years at one recent point, and water got inside the cabin. As a result there is a lot of rust and panel deformation. The speedo, tach, cluster gauges & stereo radio will need to be restored or replaced.

 

Take a deep breath and put a plan together. Taking on a project like this takes time, money, and patience. Not sure if you've done anything like this, but talk to those who you plan to use for services, see what their timetables are, and listen to their recommendations.

 

Yep, done all this before. Its the time and energy that are the limiting factors.

 

The tell on the shafts is this u joint retainer. You have what looks like a rod bearing cap and is proper for the LT and big blocks. Other small block Vettes had what looks like the threaded portion U portion of a muffler clamp.

You also mention gas tank. An original LT tank will only have one outlet to the pump and no return inlet as the Holley did not have a return.

 

Thx Makes more sense. Any experience/guesses on why the to last 2 digits on each example aren't part of the original "gang stamp"?