Author Topic: Concerns With Decking The Block Question I Need Your Help  (Read 9530 times)

mrbass

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Concerns With Decking The Block Question I Need Your Help
« on: March 02, 2012, 05:21:12 PM »
I have a numbers matching 1969 Z-28 I am thinking about rebuilding the motor. My mechanic suggested we deck the block to get the best performance. I  trust these guys to build a excellent racing engine but I am very concerned about  how this will affect  numbers on the block and the value of the engine . Am I right or wrong to be concerned how do I avoid a disaster ?

bertfam

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #1 on: March 02, 2012, 05:23:59 PM »
It's not uncommon for shops to want to deck the block. However, tell them to stop before they get to the suffix and VIN. If they don't know what you're talking about, or don't want to (or CAN'T) do this, find yourself another machine shop.

At the minimum, take several HIGH RESOLUTION pictures of the deck before anyone touches it.

Ed

Mark

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #2 on: March 02, 2012, 05:30:13 PM »
Make sure they understand (in writing if necessary and beleive me it is necessary) that if the numbers are disturbed it will affect the value of your car by several thousand dollars and you will be looking for that money from them.
Mark C.
1969 Indy Pace Car
350/300HP RPO Z11

Charley

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #3 on: March 02, 2012, 06:00:04 PM »
I had the same situation once and I made it very clear to the machinist that if the #'s got removed he was buying the car. Be very careful and clear with them because it is too easy for the guy to delegate the machine work to a employee and he machines it off and you are screwed. If those #'s get removed you have lost 95% of future buyers and don't let them tell you they can deck it and restamp the same #'s. Buyers will be able to tell and your car will take a huge hit in value.

tmodel66

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #4 on: March 02, 2012, 09:46:02 PM »
When I had my machine work done I made it point to be there. I lost a day's work and had every intention to take another day off work if they were still working on my block. Like Charley said don't let them convince you "We can restamp it and nobody will ever know".  You basically put your whole car in jeopardy if you loose the original pad stamp and they try to restamp.
Daniel  
'69 SS 350/4 speed  Fathom Green--POP

x66 714

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #5 on: March 02, 2012, 10:20:30 PM »
I wouldn't do it. Too much chance for error & then it's just another unknown Camaro. Are you going racing or doing a restoration? If you're going racing find another block or another car & let someone else have yours...Joe
See America's First, Chevrolet

1968 Z/28 Corvette Bronze. Black Hounds Tooth. 02E Los Angeles born 3/13/1968 pnt OO. Purchased March 1976
1969 SS396 Yellow/Yellow 08E Norwood born 8/28/1969 pnt 76E. Purchased April 1981

Mike S

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #6 on: March 02, 2012, 10:35:12 PM »
I wouldn't do it. Too much chance for error & then it's just another unknown Camaro. Are you going racing or doing a restoration? If you're going racing find another block or another car & let someone else have yours...Joe
I agree...get another engine. How much performance would you get by decking? Most racers today are using NO2 so dial in how much HP you want if you need a boost. Unless there is severe warpage or deep surface rust, decking IMHO, would provide little value, if any. Besides, would you want to risk blowing up the engine at the value it's worth now?

Mike
67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

KurtS

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #7 on: March 03, 2012, 02:06:27 AM »
What problem are you trying to fix? Literally millions of blocks were made without precision decking and there wasn't an issue - including all the 302 and LT1 and L72 and L78's.
Kurt S
CRG

x66 714

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #8 on: March 03, 2012, 06:03:59 AM »
It's another way for engine rebuilder to take more money from you. I've built lots of engines without line boring or decking & they run for many years without any problems....Joe
See America's First, Chevrolet

1968 Z/28 Corvette Bronze. Black Hounds Tooth. 02E Los Angeles born 3/13/1968 pnt OO. Purchased March 1976
1969 SS396 Yellow/Yellow 08E Norwood born 8/28/1969 pnt 76E. Purchased April 1981

plumL78

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #9 on: March 03, 2012, 02:11:08 PM »
Don't do it

67L78

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #10 on: March 03, 2012, 02:22:34 PM »
In 2005 i had my 67 l-78 engine rebuilt and my builder wouldn't even consider decking the block. First it didn't need it and i bet yours doesn't either. If your man says your block must be decked, get your engine loaded up and get out of there as soon as possible. Performance engine builders just don't get it about the numbers like we do. DON'T DECK THAT BLOCK!!!!

Richard

JohnZ

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #11 on: March 03, 2012, 03:11:52 PM »
Hardly any blocks need decking for a normal street rebuild, although many machine shops simply do it routinely to avoid "come-backs" for head gasket sealing issues. DO NOT deck the block, and don't use any abrasives on the stamp pad surface; that little 3"-long surface is a huge portion of the value of your car - don't touch it.
'69 Z/28
Fathom Green
CRG

68camaroz28

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #12 on: March 03, 2012, 05:06:01 PM »
Hi mrbass,
Well you read the responses so no use me stating the same ol' but I just wanted to Welcome you aboard.
Good luck and let us know how you make out,
Chick
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584

mrbass

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #13 on: March 06, 2012, 05:03:59 PM »
Well I want to thank everyone for the input . I won't be decking the block thats for sure ! 

Kelley W King

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Re: Concerns With Decking The Block Question I Need Your Help
« Reply #14 on: March 06, 2012, 08:54:33 PM »
I hear performance a lot. A stock Z motor or L78 has more in it than tires that fit can take. Unless you do some serious mods for traction that extra performance just creates MORE tire smoke. IMO
69 Z28 RS Scuncio Hi Performance
69 SS L78
67 SS Chevelle
64 Corvette
66 GTO Tiger Gold
77 Trans Am Special Edition