CRG Discussion Forum

Camaro Research Group Discussion => General Discussion => Topic started by: L79chevelle on October 24, 2020, 03:51:39 AM

Title: Jl8 brake option
Post by: L79chevelle on October 24, 2020, 03:51:39 AM
Does anyone keep track of jl8 cars along with production dates and axle build dates
Title: Re: Jl8 brake option
Post by: william on October 24, 2020, 01:38:23 PM
We have some data on about 40 cars; axle data on about 30.
Title: Re: Jl8 brake option
Post by: firstgenaddict on October 24, 2020, 09:25:31 PM
What is the latest VIN you have being built with JL8?
Reason I ask is a customer has a car which shows JL8 on the order sheet but the car was not built with JL8 -334xxx body tag - N652xxx
Title: Re: Jl8 brake option
Post by: WorkinProgress on October 24, 2020, 11:05:03 PM
My JL8 Z/28 Camaro is N652055 built 05E. Has original 3.73 QX rear.

Pictures of car is on the Trans/Am section under James Patterson.

                                             - Warren
Title: Re: Jl8 brake option
Post by: william on October 25, 2020, 12:05:41 AM
The db has a car slightly later than Warrens. It is last on the list.
Title: Re: Jl8 brake option
Post by: L79chevelle on October 25, 2020, 12:19:10 AM
Hello all ,my car is 05a with 05 05 axle date (cinco de Mayo) sp not sure
Title: Re: Jl8 brake option
Post by: firstgenaddict on October 25, 2020, 06:40:10 AM
Nicely loaded up L78 M22 fold down ZL2, F41,  car is 6526xx may have just missed the cutoff, or there were no more 3.73 JL8 axles in the pipeline, the original purchaser ended up thinking that JL8 was only available on Z28's and thus the reason his car was not so equipped...
Title: Re: Jl8 brake option
Post by: william on October 25, 2020, 04:30:20 PM
With a 334xxx body number, that car was ordered and confirmed about a week prior to Warrens. At that time, there were 3.73 axles in stock and in production; last known axle build date is May 23.

My theory, Chevrolet declined to build it with JL8. There are no known big blocks built with JL8, not even the Indy track cars. The system was a compromise from the start since a Camaro is heavier than a Corvette. A big block just makes it worse. Could be they couldn't get the system to work properly, with not only the additional weight but more on the the front wheels. Certainly not worth the additional Engineering time.

Chevrolet=Racing? a book by Paul Van Valkenburg, has some good insight on JL8. It was developed in response to what they believed was severe brake fade with the production disc/drum system. Turned out it wasn't brake fade; when the system heated up under racing conditions, the resulting expansion in the system exceeded the hydraulic capacity at the front wheels. All they had to do was switch the brake lines at the master; the rear chamber had slightly more capacity than the front.
   
Title: Re: Jl8 brake option
Post by: 69Z28-RS on October 25, 2020, 09:40:26 PM
I have seen a big block '69 Camaro with JL8 brakes; it was back in the late 70's.   I think the same owner still has it but he's difficult to get in touch with.   I've been trying for the last 2 or  3 years to get with him and document the car and brakes, but so far no luck...   (I just left him another message, so we will see)..  If I can get with him to view the car again, I'll take some photos and get the numbers etc.
Title: Re: Jl8 brake option
Post by: my69Z28camaro on October 26, 2020, 06:12:41 PM
On the subject of JL8, does anyone have a list of the casting numbers & markings for the FACTORY JL8 brake calipers? Front & rear, left & right sides, inside and outside calipers. If the OTC JL8 brake calipers are a different casting number I could use them too. There is a '69 Z/28 coming up at MECUM Indy Fall this week that claims to have rear disc brakes, but does not say JL8. So when I look through the rally wheels at casting numbers or crawl under the rear I would like to know what I am looking at casting numbers wise. Thanks
Title: Re: Jl8 brake option
Post by: KurtS on October 26, 2020, 06:52:56 PM
My 69 05C 396 had JL8 from the factory. POP shows a QU (3.07) axle. It was a Tech Center car - no idea what it did there.
Though it's pretty original, someone swapped out the JL8 axle and brakes. Can't be very many of the QU axles out there......
Title: Re: Jl8 brake option
Post by: 69Z28-RS on October 28, 2020, 02:28:49 AM
Today I talked to the owner of the '69 396 Camaro with the JL8 that I observed (all original in 1976).   He told me he still owned the car.  He has the protecto plate which he told me he would email me a photo of.   He said the rear was 3.73 Posi (QX code).   He also said the POP/paperwork was marked for The GM Tech Center, but car was first sold to someone in Atlanta, then later was traded/sold to someone here in Huntsville.   It's a 396/350hp Auto with AC car, lots of options.   I will update when I see a photo of the POP or otherwise get to examine the car...

PS.  He was a friend of the fella who had purchased my old '68 Z28.  He told me that his friend had sold the car to a man in Nashville named Art Bell...  Do any of you Nashville folks know that name?   That Z28 was a basic Z28 with few options; LeMans blue with white stripes..
Title: Re: Jl8 brake option
Post by: L79chevelle on October 28, 2020, 03:28:58 AM
All good info thank you .  It seems many axles  built in may FYI my car is also a qx code ,vin 640974
Title: Re: Jl8 brake option
Post by: KurtS on October 28, 2020, 08:34:12 PM
  He also said the POP/paperwork was marked for The GM Tech Center, but car was first sold to someone in Atlanta, then later was traded/sold to someone here in Huntsville. 
That's the same as my car. Tech Center car with the first owner in northern Georgia. I always thought it was strange that the car was sold so far away. I figured that maybe someone at the Doraville plant tagged it. But two cars with the same story....
Title: Re: Jl8 brake option
Post by: 69Z28-RS on October 28, 2020, 09:37:05 PM
Do you still own that car, Kurt??   If not, when did you own it? Maybe it's the same car???   This one is Daytona Yellow, black vinyl top, AC Auto, 396/350 hp...
Title: Re: Jl8 brake option
Post by: KurtS on October 29, 2020, 04:00:11 AM
I still own it. White, black top, L35 auto, no AC.
Title: Re: Jl8 brake option
Post by: 69Z28-RS on October 29, 2020, 01:09:15 PM
Kurt:   OK.... Not the same car.   I sent you a PM with some more info...
Title: Re: Jl8 brake option
Post by: 69Z28-RS on October 31, 2020, 01:57:15 PM
OK, some of the information I provided previously is *incorrect*, so I'm going to TRY to correct/update here.

The facts I’ve learned this week (and seen photos) are here:
1.   The ’69 Camaro with JL8 that I've mentioned before is a Daytona yellow, black vinyl top, with black houndstooth interior (76 B / 713 ).   It is a 396/350 hp, Automatic.  It also had factory installed AC (although not complete under the hood).
2.   It’s a 10A car (checking the VIN number it appears to have been produced on 4 Oct 1968).
3.   I first saw the car around 1977 when the ‘new owner’ and his friend brought it to my home to show me the car they had just purchased from the local Oldsmobile dealer – off the used lot – it had been traded in on a new Olds.   In my ‘walk around’ examination in my driveway, I noticed the 15” Rallye wheels (unusual on a 396 car) so I checked the brake calipers.   It had the 4-piston disk brakes, including on the rear axle.  At that time, the components appeared 'original' and to have been there since its build, although I didn’t have opportunity to thoroughly check numbers etc.   I informed the new 18 yr old buyer that it had a rare disk brake option, and that I would trade the 12 bolt 3.73 posi rear from my original ’69 Z28 for the rear end AND pay him more ‘to boot’ than he had just paid for the car.   He didn’t take my offer, although until that point he had not realized it had the 4WD rear.   He has since checked all the parts and told me this last week that the car has ALL of the JL8 parts including the rear and front brakes and all worked perfectly.  It appeared to me in 1977 to be a factory install – not something converted by someone (and that was in 1977)!   He was about to graduate HS, and had told me he planned to go to college in engineering; that fact helped me to locate him years later!  

UPDATE from this past week.  I called all the numbers I had for him and left a message on his work phone (hoping he still worked there).  A few days later he called me back and we talked for awhile.   He is admittedly nervous about specific data on him or his car being put on the internet, so his name and vehicle VIN and the photos he’s sent me will not be posted here, but I will post the information from the photos simply to update and clarify the information I previously posted (from my memory and my prior conclusions).

•   The car was SOLD to the end user on 18 October 1968 (only two weeks after production), but the ProtectoPlate/Warranty card  in the AUTHORIZED SELLING DEALER PLATE IMPRINT  area stamped in red block letters is  “CHEVROLET ENGINEERING CENTER, 30003 VANDYKE, WARREN MICHIGAN”.   The original customer was also identified (Atlanta GA area).
•   The original ProtectoPlate for the car identifies the factory installed components (Engine, Trans, Rear, etc).  The original engine and trans are still installed, but the differential code shows    BM0911G1 (which is for a 3.31 non posi 12 bolt), so the JLK components were apparently NOT installed in the factory as I’d believed on my ’77 viewing.  (Question:  but were they installed at the Chevy Engineering Center???)
•   The rear differential actually installed in the car is stamped    QU0129G1.  The center section cast date is A218.  I conclude that the QU rear was assembled on 29 January 1968 which is ~ a year before the JL8 option was available for order by the public!   I became curious if this rear may have been an OTC service duty rear (rather than std JL8), but the owner believes it conforms to the JL8 diff tubes (although in my opinion, available JL8 vs SD OTC rear information is very spotty and not as concise as I would wish).   
•   The QU rear prefix specifies a 3.07 ratio Posi 12 bot with 4WD (same as what Kurt posted was in his car from factory – based on the ProtectoPlate info.  I also wondered, and queried KurtS privately if it was possible that his car and this car were purchased by the same dealer or party in Georgia, and if the complete brake systems may have been swapped between the cars for some reason but KurtS said the numbers didn’t match up.   3.07 JL8 rears have to be very rare and far between I would think!  

Conclusion:   I was able to get some more specific information about this car this last week and I found out my prior information/assumption was wrong, but it does have ‘factory JL8 components’ installed although we’re unable thus far to determine how/who/when it was installed, but it was well before 1977 based on the condition at that time.   It’s strange to me for these two cars (KurtS and this one) to both have JL8 evidences (in 3.07 form) but not match to their POPs… and both being big block cars (which most people have said didn’t get JL8 installed!)…   It’s an ‘automotive archaeological mystery’ which I’d love to know the answer to!  
Title: Re: Jl8 brake option
Post by: william on October 31, 2020, 06:22:14 PM
The SS396 JL8 stories have been around as long as I can remember. There have been several built-up cars passed off as original; there was another submitted to Legends judging at MCACN a few years ago. The fact remains that if you throw enough money at it, you could build one 100% technically correct. It would even have a Protect-O-Plate. But it would not have a real window sticker, shippers copy or broadcast copies.

It's a tall order, but when a 100% original SS396 JL8 car with some of those docs reveals itself, I will be the first to celebrate.
Title: Re: Jl8 brake option
Post by: KurtS on November 02, 2020, 08:03:54 PM
Gary,
That is the in-service date, not the sales date. That's normal practice for cars that GM used. That axle is a 69 axle.
It's possible that this car was used for JL8 development - hard to tell or prove.

William,
My car is not 100% original - it has a repaint and the wrong axle and only has a POP. The car was never presented as a JL8 car by any former owner. The Tech Center stamp on the POP is an original.
I always questioned the POP, mainly cause the axle is dated exactly the same as the POP, but is a BR, not a QU. Eventually I realized that the axle is actually CBR and a year too late for the car.  What I don't know is know is when the components were swapped. I assume that someone (post-GM) swapped them out early in the car's life.
Title: Re: Jl8 brake option
Post by: william on November 02, 2020, 11:50:29 PM
I do not doubt for one minute it was built with JL8.

Problem is, the Tech Center could order virtually anything; Z/28 converts, ZL1 show cars w/special paint. Shortly after your car was delivered, JL8 was cancelled.

Did a retail buyer order and take delivery of a Camaro SS 396 with JL8 brakes? Still don't know.
Title: Re: Jl8 brake option
Post by: KurtS on November 03, 2020, 09:21:21 PM
I do not doubt for one minute it was built with JL8.
Did a retail buyer order and take delivery of a Camaro SS 396 with JL8 brakes? Still don't know.
I've seen no evidence of that so far. All Z's with JL8 except for one L65 car and one reputed 307 car. And my Tech Center car.
Title: Re: Jl8 brake option
Post by: firstgenaddict on April 07, 2021, 08:06:19 PM
Nicely loaded up L78 M22 fold down ZL2, F41,  car is 6526xx may have just missed the cutoff, or there were no more 3.73 JL8 axles in the pipeline, the original purchaser ended up thinking that JL8 was only available on Z28's and thus the reason his car was not so equipped...

I believe I found out the reason why it was not built with JL8.
 
The ordering customer opted for the 14" WW belted tires -JL8 stipulation specifically states it is not available with optional tires -  tires over rode the JL8 and JL8 was kicked out.
Similar to what happened on my old Lemans Blue 69 Z28 - ordered with rear antenna and D80 - rear antenna took precedence and D80 was kicked out. 
Title: Re: Jl8 brake option
Post by: KurtS on April 08, 2021, 01:10:01 AM
Normally when there was a conflict, the dealer was contacted to clarify the order. Sometimes that process wasn't robust. :)

This was added to the JL8 section on the site a while back:
Most JL8's were installed on Z28's, but GM documentation indicates that 27 non-Z28's had JL8.
Title: Re: Jl8 brake option
Post by: 68camaroz28 on April 15, 2021, 02:18:20 PM
Do you still own that car, Kurt??   If not, when did you own it? Maybe it's the same car???   This one is Daytona Yellow, black vinyl top, AC Auto, 396/350 hp...
That’s got to be one great car optioned like that Gary....
Title: Re: Jl8 brake option
Post by: 69Z28-RS on April 15, 2021, 03:19:07 PM
Do you still own that car, Kurt??   If not, when did you own it? Maybe it's the same car???   This one is Daytona Yellow, black vinyl top, AC Auto, 396/350 hp...
That’s got to be one great car optioned like that Gary....

I agree, Chick, and I'd love to have the car...  in spite of my not being a 'big block fan' and not knowing the origin of the JL8 components...   :)

Looking back now, I can't believe that back when I read the local ad (early 1977) for a '69 Camaro' for $900 from the local Olds dealer, that I didn't go check it out..  but I *assumed* it was probably 'just another ragged out' Camaro based on the price the dealer was asking! ...  and that was during a period that I 'checked out' almost all the locally advertised early Camaros !
Title: Re: Jl8 brake option
Post by: MO on April 16, 2021, 01:34:10 AM
Do you still own that car, Kurt??   If not, when did you own it? Maybe it's the same car???   This one is Daytona Yellow, black vinyl top, AC Auto, 396/350 hp...
That’s got to be one great car optioned like that Gary....

I agree, Chick, and I'd love to have the car...  in spite of my not being a 'big block fan' and not knowing the origin of the JL8 components...   :)

Looking back now, I can't believe that back when I read the local ad (early 1977) for a '69 Camaro' for $900 from the local Olds dealer, that I didn't go check it out..  but I *assumed* it was probably 'just another ragged out' Camaro based on the price the dealer was asking! ...  and that was during a period that I 'checked out' almost all the locally advertised early Camaros !


Sounds like during the oil embargo days. Everyone was dumping muscle cars.
Title: Re: Jl8 brake option
Post by: 6t9rsz on April 20, 2021, 05:44:07 AM
Hi all, I have a factory JL8 rear and engine with the vin that was from a mid June built Z28. I sent a PM to Kurt awhile ago and never heard back from him. Maybe he never seen it or thought I was full of it but its the real deal. I have had these for about 30 years now. I have tried a few times to locate the car but didnt have any luck. If Kurt or William would like any info for the DB just let me know.
Title: Re: Jl8 brake option
Post by: william on April 20, 2021, 02:00:20 PM
PM sent.
Title: Re: Jl8 brake option
Post by: KurtS on April 20, 2021, 09:12:13 PM
Sorry about that. I totally missed that PM. I will say that I always do better with emails. :)

Digging deeper, I never got notified of that PM. Not sure why....
Title: Re: Jl8 brake option
Post by: 6t9rsz on April 21, 2021, 06:15:29 AM
PM's sent. Sorry Bill but I cant figure out how to send pictures thru PM's.
Title: Re: Jl8 brake option
Post by: william on April 21, 2021, 10:34:41 AM
pm sent
Title: Re: Jl8 brake option
Post by: firstgenaddict on May 04, 2021, 03:52:09 PM
Normally when there was a conflict, the dealer was contacted to clarify the order. Sometimes that process wasn't robust. :)

This was added to the JL8 section on the site a while back:
Most JL8's were installed on Z28's, but GM documentation indicates that 27 non-Z28's had JL8.

Kurt,
Is it possible that because the car was so close to the end of JL8 production - the conflict could not have been remedied prior to the option being dropped?
Title: Re: Jl8 brake option
Post by: KurtS on May 04, 2021, 05:30:56 PM
Hard to tell. The order form is a snapshot in time. If the order is changed, a new form was not normally generated.
The body # tells us the order was accepted, but who knows if they contacted the dealer, the dealer approved no JL8 but did not tell the customer.
Or if the order was accepted and then the discrepancy was noted and not able to be resolved expediently.
Title: Re: Jl8 brake option
Post by: Petes L48 on June 17, 2022, 06:10:29 PM
Reviving this old thread - just saw today that the rumored 307 car with JL8 is listed on eBay. NFI.

https://www.ebay.com/itm/334476363512?hash=item4de05846f8:g:JBYAAOSwOiNiq0c8






Title: Re: Jl8 brake option
Post by: MO on June 18, 2022, 03:23:51 AM
Great car and owner!
Title: Re: Jl8 brake option
Post by: crossboss on June 19, 2022, 12:17:30 AM
Love it!
Title: Re: Jl8 brake option
Post by: Martin D on September 13, 2022, 10:16:12 PM
Hi all, bit of a story, but worth reading for the punch line!
Well its the 307 JL8 car that has prompted more research on my friend Steves '69.
He has owned if for a few years now, in storage in a partly dismantled state, as he bought it off another friend.
This year he started working on it to prepare it as a nostalgia Super Stock race car.
At the time he bought it, I said about researching it & that it could have some value over & above just another nice Camaro.
Now seeing the 307 JL8 up for sale & selling in  under 24hrs on Facebook for $63,000 (what was the price on ebay, or what was the top bid?), my friend Steve was more interested in his car!
His 69 has a disc brake 12 bolt in it, a real factory one, QU code May 5th built, the car was built in the 3rd week of May.
The 307 car in the advert stated it was the lowest powered JL8 known.
So if I tell you my friend Steve's car is a L6 cylinder car with P/G , thats a bit of err, what?
Also its an Export car, well an Antwerp Belgium one, as none were built at Antwerp in 69, unlike the 67 & 68 Camaro's, all '69's were Norwood built & shipped to Antwerp.
In '79 it arrived in the UK, & where it still is.
Why a L6 with the JL8 option? That's what we would like to find out.
So any help would be great, Norwood records?
Martin in the UK 🇬🇧
Title: Re: Jl8 brake option
Post by: MO on September 14, 2022, 04:39:06 AM
Never say never, right? Sounds like someone needs to invite JM to the UK to verify.
Title: Re: Jl8 brake option
Post by: David K on September 14, 2022, 03:42:12 PM
That’s what I say. Never say they never built it or sold it. These oddity builds will keep popping up forever. I’m liking this one already.
Title: Re: Jl8 brake option
Post by: cook_dw on September 14, 2022, 04:30:26 PM
Post some photos or email them to me and I will upload them.

darrellwadecook@gmail.com
Title: Re: Jl8 brake option
Post by: Martin D on September 17, 2022, 07:34:52 PM
Asked on the foreign built section,  yes it has the 11 3/4" discs, Vett style m/c & 4 piston calipers up front.