Jl8 brake option

[L79chevelle]

Does anyone keep track of jl8 cars along with production dates and axle build dates

[william]

We have some data on about 40 cars; axle data on about 30.

[firstgenaddict]

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

[WorkinProgress]

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

[william]

The db has a car slightly later than Warrens. It is last on the list.

[L79chevelle]

Hello all ,my car is 05a with 05 05 axle date (cinco de Mayo) sp not sure

[firstgenaddict]

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...

[william]

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.
   

[69Z28-RS]

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.

[my69Z28camaro]

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

[KurtS]

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......

[69Z28-RS]

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..

[L79chevelle]

All good info thank you .  It seems many axles  built in may FYI my car is also a qx code ,vin 640974

[KurtS]

  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....

[69Z28-RS]

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...