GM Stocker rear end
 

Are the 9” rear ends in the COPO’s considered a corporate replacement to the older stocker’s or are they limited to the COPO’s only? I think I know the answer, but I have to ask….
Thanks, Mike

Re: GM Stocker rear end
 

That's a really good question. The rear suspensions on the Chevrolet, Ford, and Chrysler factory racers are nowhere near stock configuration, which in my opinion these cars should be using the stock suspensions with the same approved modifications the older cars are allowed. Are the older stockers allowed to use the same technology as the factory built cars? I think not. Also, the newer designed engines have features which allow them to make more horspower and torque per cubic inch than the older engine designs. One item that comes to mind is a roller cam.

Re: GM Stocker rear end
 

The older IRS Corvettes have been allowed to install a solid axle in for years. The COPO rearend, which is based on a 9" Ford, is not legal in the other GM stockers.

Re: GM Stocker rear end
 

I'm not so sure about that...

"Original rear end may be replaced with another from the same
automobile manufacturer; truck rear end prohibited. Aluminum
center section permitted only on vehicles that were originally
equipped with same. Distance between backing plates may not
be changed. Any gear ratio that fits third-member case or
housing permitted. Limited-slip or ratchet-type rear ends
permitted. Reinforcement of spring perch permitted. Spools
permitted only with aftermarket axles. Aftermarket axles not
required for front-wheel-drive vehicles. Larger brakes may be
used. Replacement rear end may be narrowed or widened to
obtain original rear-end width. Bracing or beefing up the rearend
housing permitted.
Swing axle differential may be replaced with conventional
housing; stock trailing arms must be retained, may be beefed up
and adapted to housing, must retain transverse spring. Must
install Panhard bar. Frame may be notched for driveshaft
clearance. Distance between OEM backing plates and OEM
wheelbase must be maintained. Coil-over shock or four-link
adaptations prohibited. See General Regulations 2:11."

As I see it, GM's '(9")" is now in the mix. We already run aftermarket 12-bolts...what is the difference with this one? "Original rear end may be replaced with another from the same
automobile manufacturer" ;) Let the legal interpretation of the rules begin. :p

Re: GM Stocker rear end
 

The 9 inch rear end in the COPO cars, is built by Strange exclusively for GM and the COPO program. Not available to the public, unless you buy a COPO of course.

Re: GM Stocker rear end
 

"Original rear end may be replaced with another from the same
automobile manufacturer"

That wording is not in the rulebook. In my mind it makes no difference who made the housing...it is still from the same car manufacturer. Did the COPO cars not have to meet the minimum requirements to qualify for Stock classes? My Mosier or Strange 12-bolt housing was not built by Chevrolet, but are none the less considered legal...correct?

Re: GM Stocker rear end
 

OK, now, is the COPO rear end in the Camaro built by Ford or an aftermarket supplier? Seems to me most rear ends are made by Eaton,Spicer,Dana or some outside party like that. Does that mean I could put a rear end that is a facsimile copy of a 9 inch Ford,although not made by Ford specifically, in my 327 powered '68 Chevelle?With the currently increasingly more difficult to locate and expensive OEM 12 bolt housings becoming more and more of a problem, does that qualify me to install an aftermarket nine inch under it? I think of our buddy Aubrey Bruneau with his 4 speed 409 Chevy Bel Air bubbletop who could really benefit from that. The fact that Ford doesn't and hasn't produced those rear ends for 30 years or so,and aftermarket suppliers are now supplying them to Drag Pak and COPO racers under their factory race cars,(which are themselves outsourced),does that constitute a loophole through which they could be legalized for other applications? Just a thought on a boring cold night.

Re: GM Stocker rear end
 

A copy and paste of the rule book means absolutely nothing. Once again, the rules apply to some and not others.

A prime example would be a red Olds stocker that recently moved from the west coast to the east coast. It has been through tech many times and always passes. I believe it just won a divisional as well. But it clearly has a narrowed rear axle and altered frame rails. There is no other G body car that sits as low to the ground and has the tire clearance this car does. How is that possible??

A simple check of the distance between the backing plates and between the wheel wells may shed some light on this. But NHRA NEVER checks these things. They must not own a tape measure.

I doubt they even care about bogus stuff like that. Otherwise they wouldn't allow even half the junk they do. So I say, stick the nine inch Ford in. IF they catch it, as for forgiveness.

Re: GM Stocker rear end
 

Officially NOT I repeat NOT for use in ANYTHING except COPO cars. Was told that with EXTREME prejudice by GM officials AND NHRA tech when wanting to replace my 12 bolt. Huge debate on the floor at SEMA Went rounds explaining and arguing my case and was finally told"You want to use the new rear end? Buy a new car and get rid of your old one!"

Re: GM Stocker rear end
 

I thought you could buy all the required parts to build copo's drag pak's etc over the counter. If so then why not order your gm or mopar 9"? Then it would have to be legal having the gm or mopar part number affixed! The big wigs at sema argued this you say, but would tech?

Re: GM Stocker rear end
 

Yes! Danny Gracia Right in front of a drunkish Tom Compton. I was told that the "manufacturer" has final say so over the use of their product. If GM says no NHRA says NO! There were a couple of other tech and officials there too, this was last year. I think I made a little too much noise and logical sense to them. but since I was not wanting to upgrade to a 100k car my opinion mattered NOT!

Re: GM Stocker rear end
 

A copy and paste of the rulebook means exactly what it reads. If a housing is narrower than specified it is clearly illegal for use...period.

Re: GM Stocker rear end
 

GM officials have no say in the matter They submitted the new car to NHRA and NHRA allowed it in Stock which means they abide by the same rules as any other vehicle...I have never seen any separate rules governing COPO cars, have you? A flat refusal to allow the new housing would require NHRA to re-write the rulebook and put them on very shakey ground in their argument. Do you believe a swap of their current housing to a 12-bolt in the new car would be illegal?

Re: GM Stocker rear end
 

Not letting this one slide. COPO and Dragpak yes. But tell me what is nowhere near stock configuration about a CJ rear suspension, and what they are allowed to use that older cars are not?

Re: GM Stocker rear end
 

The rule doesn't save the racers money; 12 bolt, Dana, and 9" cost similar money to build right. Nor does it make the car more "authentic" or "stock" since we see a lot of cars that only had 10 bolts, or 8.75", etc. running the bigger differentials. If it is OK to look under the hood and see a non-authentic aluminum water pump, that is a lot more obvious than a non authentic differential housing.

Oh, sorry, I was interjecting logic and that has little to do with the issue.

Re: GM Stocker rear end
 

If we can get tech involved here may help the case !!

Re: GM Stocker rear end
 

Rule book states - "Distance between backing plates may not be changed."...

Another "Stock Eliminator" rule that is totally ignored anymore...

there are lots of "bogus" examples out there if you just pay attention.

Re: GM Stocker rear end
 

i was told the copo is a part # (no vin)there is no where that you can look up a part # for a gm copo rear end:confused:, thats what alows them to say older cars can't use them because its not a over the counter part sold by gm unless you bought a copo or a rolling chassis:mad:. i don't think you can even buy a 2012 camro and build a stocker with that rear end because it didn't come in any corperate car:eek:

Re: GM Stocker rear end
 

The COPO should have to use a 10 or a 12 bolt, the Dragpack cars a Dana 60 or an 83/4 Chrysler and the CobraJets a 9 inch or an 8.8 Ford unit. I am limited to a 10 or a 12 bolt, it should be the same for everyone. My point is the factory cars get to use all of the new technology components and the rest of us are stuck struggling with old technologies.

Re: GM Stocker rear end
 

2013 COPO Camaro Service Parts


DESCRIPTION

427

396

350


Engine & Long Block Assemblies


Engine Assembly

17802825

19301608

19301609


Long Block Asm

19299607

19301614

19301615


Engine Components


Harnesses and Modules


Harness, engine control

19301111

19301111

19301111


Harness, engine control jumper

19301112

19301112

19301112


Harness, alternator excite

19301113

19301113

19301113


Module, engine control (Manual)

19302703

19302704

19302705


Module, engine control, (Auto)

19301200

19301610

19301611


Harness, Fuel injector wiring

19299611

19299611

19299611


Other Engine Components








Engine Block Asm

19213580

12623967

19213580


Rear Seal Retainer Bolts

11588723

11588723

11588723


exhaust manifold gaskets

12617944

12617944

12617944


Crank Shaft

19299608

19301270

19301559


Crank Shaft Main Cap Bolt

12556127

12556127

12556127


Crank Shft Rear Seal

89060436

89060436

89060436


Crank Sprocket

12556582

12556582

12556582


Crank Bolt

12557840

12557840

12557840


Crank Position Sensor

12585546

12585546

12585546


Bolt, crnkshf pos sensor

11515756

11515756

11515756


Stud, crk/shf brg cap

12560273

12560273

12560273


Bolt/screw, cr/shf brg cap

12560272

12560272

12560272


Camshaft

88958773

88958773

88958770


Camshaft Retainer Plate

12589016

12589016

12589016


Cam Retainer Bolts

11561455

11561455

11561455


Cam Position Sensor

12591720

12591720

12591720


Bolt, cam pos sensor

11588712

11588712

11588712


Cam Sprocket

12586481

12586481

12586481


Cam Gear Bolts

12556127

12556127

12556127


Rods - Connecting

17802817

19301271

17802816


Piston

17802821

19301556

19301558


Rings

17802822

19301557

17802822


Air induction tube

19299621

19299621

19299621


Map Sensor

12591290

12591290

12591290


Throttle Body

17802828

19301616

19301616


Injector

12598646

12576341

12576341


Throttle cable bracket

19299618

19299618

19299618


Fuel Rail Fittings

19301143

19301143

19301143


TPS (Throttle Position Sensor)

17123852

17123852

17123852


DAMPER ASM

19299313

19299313

19299313


Frt Seal

12585673

12585673

12585673


Frt Cover Gasket

12633904

12633904

12633904


Frt Cover

12600326

12600326

12600326


Front Cover Bolts

11515758

11515758

11515758


Timing Chain Tens kit

12581276

12581276

12581276


HEAD ASM - W/VALVES

17802818

12629063

12629063


HEAD ASM - Bare

17802804

19302061

19302061


Head Bolt

19258707

19258707

19258707


Head Bolt

12558840

12558840

12558840


INTAKE MANIFOLD KIT

17802810

19301195

19301195


Bolt, Intake manifold

12552344

12552344

12552344


Lifters

88958689

88958689

88958689


Lifter Guides

12595365

12595365

12595365


Bolt/screw, vlv lifter guide

12551163

12551163

12551163


Gasket, valley Cover

12610141

12610141

12610141


Valley Cover

19301146

19301146

19301146


Head Dowel

12570326

12570326

12570326


Coolant Temp Sensor

12608814

12608814

12608814


Intake Valve

12591644

12569427

12569427


Intake Valve Lash Cap

12596509

Not used

Not used


Valve Locks

10166345

10166345

10166345


Retainer, intake valve

17802819

17802819

17802819


Retainer, exhaust valve

17802819

12596508

12596508


Push Rods

12593344

19301617

19301617


Intake Rocker Arms

12579615

12569167

12569167


Exhaust Rocker Arms

12579617

10214664

10214664


Rocker Arm Bolts

11588791

12560961

12560961


Valve Cover

19301147

19301147

19301147


Valve Cover Bolts

12577215

12577215

12577215


Valve cover breather cap

19299619

19299619

19299619


Oil Pan

12640746

12640746

12640746


Oil Pan Gasket

12612350

12612350

12612350


Oil Pan Bolts - Short

11515758

11515758

11515758


Oil Pan Bolts - Long

12554990

12554490

12554490


Oil Filter

89017524

89017524

89017524


Windage Tray

12611129

12611129

12611129


Windage Tray Nuts

11609746

11609746

11609746


Pick up Tube

19301149

19301149

19301149


Pick up Tube Gasket

12584922

12584922

12584922


Nut, Pick up Tube

11609746

11600746

11600746


Bolt, Pick up Tube

11516521

11516521

11516521


Oil Pump

19301144

19301144

19301144


Oil Pump Bolts

11515758

11515758

11515758


plug, eng blk oil gal

9427693

9427693

9427693


Oil Pressure Sensor

12621234

12621234

12621234


Oil Dipstick tube

19301148

19301148

19301148


O-ring, Oil dipstick tube

24504031

24504031

24504031


Bolt/screw, oil dipstick tube

11588736

11588736

11588736


Other Components


Alternator

88864377

88864377

88864377


Mount kit, Alternator

19299546

19299546

19299546


Coil, ignition

12611424

12611424

12611424


stud, coil mtg bracket

12554211

12554211

12554211


Brkt, ign. Coil mtg

12580353

12580353

12580353


bolt/screw, ignition coil to bracket

11516424

11516424

11516424


wire asm, spk plug

89018057

89018057

89018057


sheild, spk plg wire

15336959

15336959

15336959


pipe asm, eng cool air bl

12602544

12602544

12602544





Body In White (BIW)

19243374




BIW (10-7-13).png




2013 COPO Graphics




Graphics Package - CHEVY RACING BLUE

23162259




Graphics Package - WHITE

23162260




Graphics Package - FLAT BLACK

23162261




Graphics Package - INFERNO ORANGE

23162262






2013 COPO Graphic Pkg.png

2013 COPO Graphic Pkg II.png


This is a list of the only parts that are available over the counter for the COPO

Re: GM Stocker rear end
 

Nowhere in the rulebook does it mention part numbers required. The new rear-end comes in the new car, the car is approved for Stock, therefor the housing is from the same manufacturer regardless of who built it. As long as the width is legal for the donor car it should be accepted.

Re: GM Stocker rear end
 

Through the woodland, through the valley....

Re: GM Stocker rear end
 

Just trying to make it harder to campaign an older stocker. Their way of slowly trying to push the high dollar cars on the people who want to compete.
It is going to bite them in the ***** in the long run.

Re: GM Stocker rear end
 

If that be the logic I will just go run NMCA...:p

Re: GM Stocker rear end
 

What's the point of wanting to run a 9" rearend ? Strength ? A typical 12 bolt is lighter, and has better efficiency. Why would you want to use a slower rearend ?

Drag Pac, Cobra Jet, and COPO are all inclusion cars (paragraph 3, section 10A), which are not "factory-production assembled, showroom available, and in the hands of the general public" (paragraph 2). That is why the 9" is not considered an OEM rearend for a Chrysler or GM, and therefore not a legal replacement .

Re: GM Stocker rear end
 

Don't want a 9"...just saying by the rules it is fair game.

"OEM may apply for inclusion of any special production runs into
the Official NHRA Stock Car Classification Guide. Special run
must include a minimum of 50 units of an already accepted body
style, need not be showroom available. Applications evaluated on
an individual basis. Acceptance will not imply precedent."

Nowhere in that paragraph does it imply it is not a legal part. Once included in the Stock category it is the same as any other car in the family. NHRA is going to have to include more wording in the rulebook to convince me otherwise.

Re: GM Stocker rear end
 

Somewhere in this conversation I miss the urgency of the argument and the "purity violation" factor. There are so many aftermarket rear ends in use now (how many 12-bolt rear ends did GM make that would bolt into a 3rd-4th generation F-body?) that the argument loses its effectiveness. If you think its necessary to keep mfr to mfr consistency, I guess that's okay. In the "old days", it had to do with durability, but the aftermarket has solved that, so I do not see why anyone would think there is an advantage using a rear end assembly based on another manufacturer's design.

Re: GM Stocker rear end
 

Thank You! This ship sailed years ago.

Re: GM Stocker rear end
 

Finally, some logic enters the discussion...thank you.

Re: GM Stocker rear end
 

Thanks, I didn't expect this much conversation on the request. My reasoning for using the 9" was the convenience of gear changes in a multi purpose vehicle. Additionally, the 9" style rear might look a closer to the original 56 rear than a 12 bolt....and there's a 9" laying in the shed.
Thanks for the responses.
Mike

Re: GM Stocker rear end
 

See post number 26...

Re: GM Stocker rear end
 

once upon a time Strange made a 9" 3rd member that used 12 bolt gears....would THAT be legal in a 9" ford/mopar/chevy not-quite-a-stocker?

Re: GM Stocker rear end
 

I think the point of this whole discussion is the factory cars are allowed to use rear ends, springs, and overall designs that are nowhere near the OEM configuration. In the old days it would have been classified as a modified production car. I just read the aftermarket has has available OEM type rear ends that are capable of withstanding 1,000+ horsepower for the Challengers. The factory cars should be running OEM design rear ends like the rest of us. Then there is the argument the Corvettes were allowed to eliminate the IRS yes but, they had to run a GM rear end. Also, in those days, the aftermarket wasn't making durable IRS components to take the punishment because of low demand, but it is a different story today.