Does anyone know what the market value is for a 1970 454 LS6 with 1971 LS6 aluminum heads? The engine is a GM crate high compression LS6 454 (11:1 CR with closed chamber heads), now fitted with 71 LS6 open chamber aluminum heads (CR 10:1), LS6 low rise intake, LS6 rods replaced with L88 rods/ boron rod bolts, carb to pan with Holley annular discharge venturi 850 DB carb, GM 11 CR pistons std. bore, tool steel wrist pins, LS6 crank .010/.010, big push rods and guides plates, Heads 3 angle valve job, comp cams springs, titanium retainers, lash caps, comp cams XE292S, solid lifters, comp cams steel roller rockers, Brodix valve covers, new cam bearings, HV oil pump, double roller timing chain, zero decked, balanced and blue printed. Engine only has about 5000 miles on it since new and next to nothing since last refresh in 1995. Street engine not drag race engine.

I see HP 396, 427 and 454 425 HP on ebay for $25 to $32K. What should I ask for this rare engine? Is it best to refresh again and install LS6 cam and H rockers w/stock valve covers?

 

Moving to general discussion, this is a “whats it worth?” Thread, not a sales ad.

 

I sold a Correct built 200 mile 1971 LS-6 engine that was complete intake to pan. with all the correct corvette numbers, except total blank engine pad, on BAT for $9,600, about two years ago. Hope that helps. Jim Wallace

 

What is on the front pad as far as stampings?
How about date codes on the heads or block?
If you have any of those that someone wants, you have increased value there.

Cams are very personal, and an XE292 is far from stock, maybe 10-15* larger than a stock LS6 cam.

I have $13K total in my LS6 clone, and none of my date codes match!
I spent $2000 for my '78 dated 074 heads, and I passed on a correct date coded block for $2400 and just went with a generic '80 4 bolt block for $300, etc. etc.

I would guess neither yours nor mine is worth more than 8K to someone.

 

yes thanks. Not sure why some of those engines on Ebay are $30k.

 

I see a dozen BBCs for sale between 4 & 15K. Brand new blueprint engines are 8k.

The only one I see at 25K is a date stamped and code correct LS6 over the counter CE code warranty replacement engine.
That is why he is asking so high. He thinks he found long lost gold. But I would be shocked if he gets it.
GM sold thousands of these over the counter LS6 engines in the 70s & 80s.
If it is a 70-71-72 dated motor, it may be worth more than 10k to a Chevelle guy, to fake an LS6 Chevelle.
It is worth nothing special to Corvette people. They would spot a fake from a mile off.
JimWallace above is one of the best C3 LS6 experts around, and he sold a correct C3 LS6 engine for 9K.
That may well be a 1 or 1 datapoint.

The one you are talking about is not a C3 correct one.
I only say that because you mention 1970.
The exact codes and dates may make it worth more, if correct.
They only built 188 LS6 Corvettes. So very few customers. And only if the dates match.
There are even fewer C3 guys who like me, want a look-a-like LS6. Most others, if going that route, are going for 496, or 540 strokers.
The Chevelle market for this motor is much larger, in the 6000 range IIRC, and those guys are less disdainful about mods, or date matching.
Otherwise...meh.

So if you have any hope of getting more than a Blueprint engine costs, you must cough up all the date codes, stampings and part numbers.
And they need to mean something to someone.

 

Yes thanks just trying to get some data points. Not trying to pass it off as an original 1970 or 71 LS6. I will need to check dates codes to see what is what. I have had the engine in my 69 427 Conv. since 1986 but I also have a date coded 427 390 HP sitting in the shop. I am thinking of pulling the LS6 and putting the 427 back in so that some day when I sell the car it will be more correct. I am sure the LS6 is worth a bit more than the 427. Cheers.

 

I'm guessing it sounds pretty nasty and pulls pretty hard!
Cool ride in a vert.

 

10k is the ceiling on this assuming it is in perfect running condition.
Pull the carb and Brodix covers......nobody who wants one of these wants either of those items.....sell it sans carb......with stock valve covers.
Problem is that you have to find someone who wants this specific engine.......if you can't, it is just another well built BBC.
The other BIG issue is if this really does have 71' LS6 heads on it.......it better have at least the largest GM dome that came with Closed Chamber heads......even with a 19cc dome, you are at like 9.5 to 1.......which is kinda soggy with that cam......

Jebby

 

I know this is an older thread but it got me thinking. I just got my block back from the machine shop. Late 1989 over the counter LS6 replacement block. Now I have new in box GM steel crank, 7/16 dimple rods, new Icon pistons +.030. I was getting ready to assemble the short block for my 66 but looking at BAT and eBay, are these really bring those kind of numbers?
What say you on price for this?
I have a flat LS6 intake and new in box GM Corvette oil pan. Maybe I should round up some LS6 heads and sell complete.
Looking for feedback on value of short block or complete engine value for replacement LS6 counter engine, fresh build.
Anyone?

 

It's a great place to start if you are going to actually build and run it. If you are inclined to sell this stuff, you probably want to hard stop where you are at. The market for these "old school" parts is getting pretty small. Only way to sell anything is to take a bath on it or wait a LONG time. All the cool kids are spending stupid money for LS conversions and EFI. -JMO.

 

The market for LS6 C3 customers is extremely small.
Many thousands (~5500 IIRC) were put in '70 Chevelles, so I would think that would be your most likely market.
If I had to guess, more of them exist now than Chevy ever made LOL.
They seem to be everywhere. I saw 2 on Friday at a small local cruise in.
A CE block might not bother them as much either.

 

I have two LS6s in my garage right now! I don't know if that makes me a cool kid or not, but I'm certainly done with carbs.

If this is the engine you want to run, build it and run it! Otherwise, absolutely sell it right now, as is. I've seen lots of "freshly assembled, never run" engines on Facebook and elsewhere. That seems incredibly suspicious and I would never consider buying one. Better to buy a pile of parts, then at least you know what you are getting, and can put it together the way YOU want it.

 

Not sure how this compares, but found in the sold section on eBay:

https://www.ebay.com/itm/20505225210...Bk9SR9aNt5OKZg

 

Jebby has a good point.
11:1 is a little high for a good tune on today's pump gas.
The late 074 open chamber Al heads do flow better, if you get the compression right.

I set my CR to 10.5.
With my 119cc O.C. 074 heads that took:

• Icon 783 forged pistons
• .290" high 27cc piston domes
• block decked .015" for .000 to .001" deck height
• .039" head gasket
• 10.5 CR
• 8.0 DCR with LS6 similar HR 232/242* duration at 71.5* IVC
• that should run fine on 93 octane with a good performance ignition curve

If you do not deck it, to keep the pad numbers, that will cost you around .35 CR to 10.1
Then the dynamic starts getting low at 7.7 DCR and you lose a good quench height

Compression is king!

http://www.wallaceracing.com/cr_test2.php
http://www.wallaceracing.com/dynamic-cr.php

 

Thanks guys for the reality check.
To the OP, didn’t mean to hi jack your thread.
I’ll go ahead and assemble the short block with lots of pictures and the decide what to do from there. Sell for a really good offer or keep it, finish it up and put in the 66. Again, thanks to all.

Fresh machine work

Fresh paint

 

What would you build instead? The short block IMHO is not worth a bunch over any other 454 short block....the pancake intake was designed for the Vette but was on the Chevelle too....it is a specific piece that to me in worthless unless you have the whole car....it was for hood clearance and not power....it is surpising for a flat intake but not great....
I say put it together and build what you like.....the line for $10,000 454's is pretty short.

Jebby

 

makes me curios what I can get for the two (427 and 496) Zl1 1969 aluminum engines in my basement for past 40 years I can get lol

 

Thanks Jebby.
I understand and don’t disagree. I also thought, if I sell it then I have to start over and with this I know what I’ve got.
The block is # 10069286 with a casting date of June 27 1989. From what I have found out, this was a last run of Mark IV blocks for over counter sales as truck and LS6 replacement. All were 2 piece rear main seal, all were 4 bolt mains and some other improvements for Gen V but doesn’t say what. If I understand correctly the Corvette LS6 had aluminum open chamber heads to lower compression while the Chevelle LS6 used closed chamber cast iron heads, but both used the same short block and camshaft. Both of these heads are bringing more money than newer AFR or Brodix, and of course do not flow nearly as well. Soooo….with a very limited C3 market, and no where near correct date code for Chevelle folks I am leaning toward keeping it and continue on for my. 66 C2. Again, thanks to all.

Casting number

Date code

 

The 70 & 71 LS6 used different pistons, as well as different heads.
1970= 3963550 or L2349F
1971=12529559
It took both to have the 2 digit CR drop from 11:1 to 9:1.

Agreed just build it your way.