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'71 LS6 questions

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Old Jan 8, 2002 | 01:18 PM
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Default '71 LS6 questions

A friend has a '71 convertible his dad bought new. Says it's an LS6 . Did they put 425hp LS6 engines in convertibles ? Haven't checked #'s or tank sticker yet , but have seen car and it looks original except for hood paint (custom design work). Any other special things to look for to determine correctness ? Thanks , Geo
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Old Jan 8, 2002 | 01:22 PM
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Default Re: '71 LS6 questions (geopar)

Yes thay did put LS-6s in 'verts too. I've allways wanted one, but never could afford to buy one so I build one :D ! :cheers:
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Old Jan 8, 2002 | 02:00 PM
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Default Re: '71 LS6 questions (groovyjay)

Just talked to owner of LS6 , and he says that his dad rebuilt the engine to LS7 specs(higher compression , different cam and springs , used all GM parts). He says that fuel tank was replaced and doesn't know if sticker is still findable . He's going to look for any original paper work and let me know what he finds . What is this vette worth ? Does engne modification hurt value ? He says it's the original block , heads , and most other engine area parts . Geo
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Old Jan 8, 2002 | 02:03 PM
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Default Re: '71 LS6 questions

Thinking about buying it? :)

Not a bad choice if you are... The 1971 LS-6s have been undervalued for years. Chevrolet did a nice job getting this car into production considering what was happening to performance cars at the time.

The LS-6 was available in either body style.

As far as distinguishing features... The aluminum heads are a hint as to originality, although the 3946074 heads are really pretty common. The block should be casting 3963512 (common to many big blocks during the 1969-71 time period). Intake could be either 3967474 or 3963569. Carburetor should be 3986195 (R4803A) with the four speeds and 3986196 (R4802A) with the automatic. All LS-6s had transistor ignition. Tachometer should have a redline beginning at 6500 rpm. Transmissions available included the M-21, M-22, and M-40 (the two manual transmissions were equipped with a dual disc clutch). The LS-6 was also available as part of the ZR-2 package which included heavy duty power brakes and suspension in addition to some restrictions on ordering certain options.

Some additional information about the car would be great... It would be helpful if you can provide the VIN, casting, and stamped numbers.

Regards,
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Old Jan 8, 2002 | 02:11 PM
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Default Re: '71 LS6 questions (Rowdy Rat)

Listen to Stan - he knows his stuff. AND definately get that VIN #. Then even if you don't buy it I can still add it to the registry...uhm...ya... I mean then you will know for sure if it's a matching number car. No alterior motive here ;)
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Old Jan 8, 2002 | 03:08 PM
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Default Re: '71 LS6 questions (lbell101)

What about a value range ? Do the engine mods hurt value ? I'm planning on going over the paper work and #'s this afternoon ( vette is 5 miles from my house :) ). Strange how we look all over for vettes , then one pops up right in your own back yard . I'll post all info when I get it . Geo :seeya
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Old Jan 8, 2002 | 05:03 PM
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Default Re: '71 LS6 questions

What about a value range?
For a Bloomington Gold Certified or NCRS Top Flight car... Probably around $50,000-$55,000 for a coupe, $65,000-$70,000 for a convertible. Unmolested original cars may bring more. A car that has been changed substantially or has other issues will bring less. Considering the dollar value involved, this is a situation where you want to have someone well versed in these cars along when you examine it. I think that Allan mentioned the Car Craft drag test LS-6 coupe is currently for sale at right around $50,000 and that car almost certainly has a replacement engine.

Do the engine mods hurt value?
It depends (real definitive answer, huh? :) )... What has been done to it? If the block hasn't been decked or replaced, you're in good shape. Just about anything else for the engine can be replaced... For a price. In general though, the value will be affected with a car like this.

I'm planning on going over the paper work and #'s this afternoon ( vette is 5 miles from my house :) ). Strange how we look all over for vettes , then one pops up right in your own back yard . I'll post all info when I get it.
I'd be really interested in what you find out! I am rarely that lucky when it comes to locating cars... I always seem to find "just the right car" three states away...

Regards,
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Old Jan 8, 2002 | 05:42 PM
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Default Re: '71 LS6 questions (Rowdy Rat)

Only 180 (or 188?) LS6 vettes according to GM, and one year only. Performance rivals L88. So why so "cheap" ? Why not $100k ++ ? They are relatively easy to fake. I wouldnt risk paying $50k for a clone. So I would need a fully documented car.... maybe even an original owner. Then I probably would have to pay $100+ !! MJ
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Old Jan 8, 2002 | 05:44 PM
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Default Re: '71 LS6 questions (geopar)

the redline for the LS6 is like 6000 rpm isn't it? not 5600 as on LS5. check the tach.
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Old Jan 8, 2002 | 09:58 PM
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Default Re: '71 LS6 questions (geopar)

ttt
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Old Jan 8, 2002 | 10:06 PM
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Default Re: '71 LS6 questions (MNJack)

This is a one owner , original , factory ordered LS6 (according to my info--not yet confirmed!!???) I was not able to get more info today , so , we'll see!!?? Interesting though , price ranges from 30K to 150K !????? What's up here ? Seems unlikely that these could be worth more than an L88 !? More info needed , thanks , Geo
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Old Jan 9, 2002 | 10:53 PM
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Default Re: '71 LS6 questions (geopar)

Did you get anymore info on this?
It would be cool if it really is a LS6.
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Old Jan 9, 2002 | 11:08 PM
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Default Re: '71 LS6 questions (geopar)

Here is a link to a car Proteam had for some time, a '71 LS-6 converible Bloomington Survivor, Top Flight etc.

http://www.proteam-corvette.com/cars/250R.htm

It says sold $80,000 24/7

I believe that before it was sold the sale price was down to $60,000
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Old Jan 10, 2002 | 01:13 PM
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Default Re: '71 LS6 questions (geopar)

Go here dude, they have one for sale for 49900.00. This is a steal, if the documentation checks out. http://www.corvettelady.com
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Old Jan 10, 2002 | 01:53 PM
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Default Re: '71 LS6 questions (Jazn74)

just been working on a 71 LS6 auto coupe in Canada, driver but will need cosmetic resto its around $25k canadian...........................

cheep cheep but still a lot of money to spend..........
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Old Jan 10, 2002 | 02:54 PM
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Default Re: '71 LS6 questions (Geoff H)

PLEASE!!!! Get that VIN# for the registry. Like mentioned above Higher RPM redline, sway bar on rear end, one fuel line to carb (no return). But, as you can imagine, this can all be fabricated. The only way to be sure is by the tank sticker, or maybe an NCRS judge can tell you whats original and what has been added.
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Old Jan 10, 2002 | 03:47 PM
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Default Re: '71 LS6 questions (Geoff H)

just been working on a 71 LS6 auto coupe in Canada, driver but will need cosmetic resto its around $25k canadian...........................

cheep cheep but still a lot of money to spend..........
Where is he at? Anything I can help you with?
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Old Jan 10, 2002 | 06:49 PM
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Default Re: '71 LS6 questions (SuperFast80)

Ok , here's what I've learned so far . VIN 194671s113063 , Block 3963512 , L17 70 date cast ( this was on the top right of block - not on lower rt side like earlier BB's - is this correct ?) Pad stamping matches last #'s of VIN w/CPX , intake 3963569 , heads 3946074 (didn't see a date cast) , trim plate H24 build , 420 int , 989 paint , this all matches . tach yellow @ 6000 , red @ 6500 , mileage 60,233 , auto , ps , pw , radio , pb , ( no dual pinned front calipers) , TI amp in place w/wire plug (not connected), but running later HEI . June 1971 Texas inspection sticker on windshield . All body panels appear original buy there has been some minor repairs to both front fenders , original interior (not to bad-seats show wear , small cracking on driver's arm rest and at rear of panel whare it wraps under), two tops , crome and stainless very good . Now for the not so good :DOES have a fuel return line -not hooked up ( I know this is incorrect for a '68 435 car , but is this correct for a '71 LS6 ? Missing exhaust manifolds , TI dist. , valve covers , fan and clutch (cooled w/two electric fans) , surface rust on straight frame , front birdcage mounts appear to be a little rusty , and windshield cracked bottom right . Owner's son thinks that the manifolds , tach ,fan and fan clutch and v.c.'s are "around somewhere" . Oh , no tilt/tele . Car has been stripped and repainted (1989) w/GM original paint and color. Seat belt #'s are 45 E 70 . Fuel tank was replaced because it leaked (still in barn , but no sticker) . Owner still looking for original paperwork , we'll see . That's all for now , Geo
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Old Jan 10, 2002 | 07:23 PM
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Default Re: '71 LS6 questions (geopar)

Geez - I don't see any problems with the numbers. Definately LS6 numbers. Tim tag date matches build code month which you say matches the engine stamping. Any evidence of restamping on the block?
Damn - I wouldn't be able to sleep without getting that paperwork!
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Old Jan 11, 2002 | 11:51 AM
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Default Re: '71 LS6 questions

Ok , here's what I've learned so far . VIN 194671s113063 , Block 3963512 , L17 70 date cast ( this was on the top right of block - not on lower rt side like earlier BB's - is this correct ?)
Looks OK... The location for the casting date is correct; it moved from the right side of the block by the oil pan rail to the the top right of the bellhousing mounting flange approximately midway through the 1969 model year.

Pad stamping matches last #'s of VIN w/CPX
If I may ask, what was the complete information from the stamp pad (both the complete assembly date and VIN derivative stamps)? You wouldn't happen to have a high resolution digital photo of the pad? :)

intake 3963569 , heads 3946074 (didn't see a date cast)
The casting dates for aluminum heads are on the underside of the head so you won't be able to see them with the heads installed.

trim plate H24 build , 420 int , 989 paint , this all matches . tach yellow @ 6000 , red @ 6500
The yellow zone should start at 6300 rpm... I'm betting that is where it's at.

mileage 60,233 , auto , ps , pw , radio , pb , ( no dual pinned front calipers)
The dual pin calipers were only included as part of the ZR-2 option... I don't believe that an automatic transmission was available with the ZR-2 option in 1971 and I am unaware of any ZR-2s built with an automatic transmission.

TI amp in place w/wire plug (not connected), but running later HEI
The TI amplifier box in place is a good sign...

June 1971 Texas inspection sticker on windshield
How long has the car been off the road?

All body panels appear original buy there has been some minor repairs to both front fenders
Not uncommon at all... A truly unhit 30 year old Corvette is quite rare. My guess is that you'll find additional "battle damage" once the paint is stripped. I gather you poked around the underside pretty well? Original body panels are quite different than anything outside of period replacement panels and a quick inspection should determine what they are.

original interior (not to bad-seats show wear , small cracking on driver's arm rest and at rear of panel whare it wraps under), two tops , crome and stainless very good
Sounds like the car is pretty complete and in decent shape.

Now for the not so good :DOES have a fuel return line -not hooked up ( I know this is incorrect for a '68 435 car , but is this correct for a '71 LS6 ?
Contrary to my post prior to editting, there should be a fuel return line on an LS-6 equipped car. MJ and Cam address this in their posts which follow and I've revised this post to avoid any confusion.

Missing exhaust manifolds , TI dist. , valve covers , fan and clutch (cooled w/two electric fans) , surface rust on straight frame , front birdcage mounts appear to be a little rusty , and windshield cracked bottom right. Owner's son thinks that the manifolds , tach ,fan and fan clutch and v.c.'s are "around somewhere"
Not a big problem if he can't find them... Nothing that money can't solve anyway.


Oh , no tilt/tele . Car has been stripped and repainted (1989) w/GM original paint and color. Seat belt #'s are 45 E 70 . Fuel tank was replaced because it leaked (still in barn , but no sticker) . Owner still looking for original paperwork , we'll see .
I guess someone didn't like Warbonnet yellow... :)

The fuel tank/build order situation may be another red flag... What's the story behind that? Typically, fuel tanks are replaced either due to damage to the rear of the car or rust through. You mentioned a rusty frame... Is rust that big a problem in Texas? I thought only those of us here in the northeast had to deal with that. You would think that someone who knows that their car is relatively valuable would have saved the build order copy as well (assuming it was still on the tank). As I mentioned, I'd be interested in hearing more about this.

As far as paperwork goes, when you do inspect it, make certain that it really is original. There are some excellent reproductions available for most of the items typically used to document cars.

Regards,


[Modified by Rowdy Rat, 3:04 PM 1/11/2002]
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