Tally Ho

There is a 70 LT-1 convertible for sale locally that I'd like to check out. How can I quickly verify it is a true LT-1 car? The owner is advertising maintenance records back to 1976. It does not have AC from what I can see. He's also advertising it as an "older restoration". It has both tops and is Marlboro maroon with what appears to be a saddle interior. The pic in his ad is not real clear. It is a 4 speed with PS, PW, tilt, and rallye wheels. Where would I find the block stamp to verify it's original? Thanks for any and all help.

early shark

Passenger side front of engine.

jaxlt1

1970 LT-1's did not have A/C as an option.

Iceaxe

The 1970 LT1's all had a tach with a 6500 rpm redline. The 350/350 had a 6000 rpm redline and the base was also different with a 5500 redline. I've notice the tach's are seldom correct in the clones.

Tally Ho

Thanks. I know that. The 72 is the only one that came with AC. I am looking for things specific to the LT-1.

Tally Ho

Thanks. I'll check that first.

Easy Mike

Ask the seller if there is any factory documentation available on the car.

theblackvette

Single return fuel line and redline 6500 tach. Check stamp pad and VIN and trim tag. Take lots of pictures. Documentation is the best but a nice solid car speaks for itself.

joewill

the 6500 rpm tach is LT1 ( and the much more rare LS6 for 1971) only. that is the hardest to clone when the car is faked since there were so few of them.. don't know if you can even buy a a 6500 red line face for the tach.. I suppose one could somewhere..

also look for transistor box on engine compartment, emissions sticker behind the master cylinder, console tag says 370 HP, stencil scheme on the hood, ribbed cast aluminum valve covers ( although these are also 350 hp L46). probably several others that the experts here will chime in..

check the stamp pad, the casting code of the block and heads, the date code on block and heads, trim tag to make sure the date lines up with the cars birthday for the VIN, holley carb, aluminum intake

of course all of it can be faked..

at least check the stamp pad, date code on the block, tach red line and transistor box.. if these pass then chances are much greater.. then you can go in with a fine toothed comb to check all the other intricacies.

Mike Ward

Don't take this the wrong way, but if you have to ask this question, you're not in a position to tell the difference between an original car and a fake.

Hire an inspector.

kenba

Also LT-1'S had a BB core support & radiator. No cool can. Early cars had a 6 QT oil pan.

20mercury

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 piticular order.

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

2nd. Emmission 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 whers one had been mounted.


7th. All 70 / 71 LT-1's had Tranisitor 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 on line 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 /71 LT-1 Aluminum valve covers should have a rubber oil cap not a twist in. These covers are very hard to find. All the catalouges sell the twist in cap style.

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"

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.

Sounds like a very nice Corvette, if you decide to pass, please post a picture! Even if a "fake" LT-1, it might be a great deal if priced accordingly. IMHO, the key is to pay fair market price for what it actually is!

theblackvette

I missed that original comment about location.

Even though I THINK I am pretty good at spotting garbage no way would I EVER take a chance forking over $$$$ for a car without at least having another pair of eyes take a look at a car. On EVERY car I was interested in actually purchasing I had someone else go through the car that is much more experienced than me.

Do NOT do this yourself. It will be the biggest mistake you could make.

Tally Ho

No offence taken. I've been involved in the Corvette hobby since 1985. Since cloning runs rampant lately I wanted to get pointers from forum members as there is no one locally I trust. The red flag on this car sight unseen is the asking price seems low at $24K for an LT1 conv.

theblackvette

Or may be priced realistically due to the condition.

There are REAL sellers out there that know exactly what they have!

Crafty12

Here is a link to the thread I started when I was looking at my 70 LT1.

List is on the second page.

http://forums.corvetteforum.com/c3-g...ting-tips.html

joewill

it really depends on the price of the car and the OP's requirements. is the car priced as a true original LT1, or priced as a base engine car? is the car priced based on originality or condition or both?

as stated, if the OP does not know about stamp pads. my advice is to look at the obvious characteristics, maybe share some pics with us and let us pick apart the car.

rookies should throw out the numbers book and look at condition. We rarely see a numbers correct car in good condition that passes most major LT1 characteristics. and not rusted out in the usual places. when it does pass it is priced into the stratosphere.

its a local car so it is not such a major effort to do some basic homework before you bring in a knowledgeable and expensive inspector.
but yes absolutely, bring in some inspector if the seller is asking LT1 money for that car before you pull the trigger.

at 24K is it either not a true LT1 that passes most characteristics, or bad condition, or both. or else it would be sold by now. especially a convertible....

theblackvette

Let's see some pics or please post a link to the ad so we can take a look at this car and sick the dogs on it. You will be glad you did!

Tally Ho

That's why I came to you guys for advice. I plan to call the owner tonight and set up a meeting to look at the car. I will bring my camera. As I said, knowing the value of these cars the asking price seems low.

Easy Mike

True, but there are many more sellers who do not actually know what they have and bandy about LT-1, L-82, and L-88 when they have an L-48 car.