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Like many before me, the correct speedo cable clip is a difficult part to find.  Some cars have 2 holes in the tunnel and use 2 clips in the tunnel area, while others have one hole in the tunnel.  In addition, there is a hole behind the ignition coil on all cars for another clip, close to the cable's grommet, just before where the cable enters inside the car.

One restoration parts supplier offers two versions of this clip p/n 3772324, one of which is described as "assembly line correct" at a higher price.  I've tried installing this "assembly line correct" clip and find that one of the short locking fingers breaks off when trying to get it into the sheet metal hole and/or when expanding the locking fingers.  This happened with two of these clips.  Reviewing posts from others on these clips, it is apparent no one is making a workable version of it.

In the meantime, I've found another style clip that does a great job of supporting the speedo cable, in any of the 2 or 3 locations for a speedo clip and securely fits into the existing approx 5/16" drilled hole in the sheet metal.  The clip I found is actually a MoPar brake line clip for use with armored brake tubing (measures approx. 5/16" dia. over the armor/spring material).  It was used extensively on 1960's and early 70's MoPar cars.  This clip not only fits the existing sheet metal hole nicely, but also gives a secure fit to the Camaro's speedo cable.

Until such time as I can find the correct style Chevy clip that actually installs, expands the locking fingers properly without them breaking off, and stays put, this MoPar clip is going to be used to keep the speedo cable properly routed.  They are available from any of the MoPar restoration parts suppliers.

I have also used Sta-Bil for a few decades with good results.  About 10 years ago, I switched over to the ACES IV stabilizer and octane enhancement product from BND Automotive.  It equals the performance of Sta-Bil when it comes to keeping fuel fresh over long periods of storage.  But the ACES IV product has other other significant advantages over Sta-Bil.  It does a very good job of enhancing the octane level of unleaded gas, something Sta-Bil does not do.  It also reduces ring/bore wear.  Both of these advantages have been documented by Automotive Engineer/Racer/Tech Writer, David Vizard, in extensive A/B dyno tests he has run.

I was rooting around in the trunk of my 05E Norwood '69 Z28 recently and I discovered this small pad tucked up close to the rear seat back.  Does anyone recognize what this may be, assuming it came with the car?  If it did, could it be a protective pad to prevent the bumper jack from scratching the chrome on the bumper?

April 2026 Update:

Good news!  A fellow CRG member, known to many of us, has volunteered to offer their original '67 Z28's List #3910 Holley carb for me to gather needed information that will help me to complete a forthcoming database of fixed and changeable tuning orifice diameters, and other features, on 1st Gen Z28 carbs.

I will be visiting this volunteer in July, 2026 and complete the List #3910 portion of the database later that month.  This will leave the very low volume List #3911 carb, used exclusively on California bound '67 Z28's with the K19 A.I.R. smog control system, as the only missing data.  I suspect my chances of having anyone step forward with one of these List #3911 carbs, complete and in its original unmodified condition, are about nil as only fraction of the 602 total '67 Z28's were delivered to California.

There is a possibilty that the List #3910 & #3911 carbs were identical as far as certain drilled orifice dia's are concerned, but whether this is true or not is unknown to me at this time.

The primary metering block used on the List #3911 carb is stamped with the ident no.: 5462 on its top surface.  Does anyone have one of these 5462 metering blocks they would allow me to measure various hole dia's, or agree to let me send various size numbered drill bits to you for you to measure these few holes?

Maybe someone out there has a List #3911 main body that would yield the air bleed hole dia's?

Thanks for your help.  It is still my desire to have the CRG publish the data on the website when it is completed.

Again, if anyone with a List #4053 carb (used on all '68 & '69 Z28's) would like to confirm the dia's of any tuning holes in their carb have been drilled out or not, please send me a PM and I will respond.

Chuck B.

April 2026 Update:

Good news!  A fellow CRG member, known to many of us, has volunteered to offer their original '67 Z28's List #3910 Holley carb for me to gather needed information that will help me to complete a forthcoming database of fixed and changeable tuning orifice diameters, and other features, on 1st Gen Z28 carbs.

I will be visiting this volunteer in July, 2026 and complete the List #3910 portion of the database later that month.  This will leave the very low volume List #3911 carb, used exclusively on California bound '67 Z28's with the K19 A.I.R. smog control system, as the only missing data.  I suspect my chances of having anyone step forward with one of these List #3911 carbs, complete and in its original unmodified condition, are about nil as only fraction of the 602 total '67 Z28's were delivered to California.

There is a possibilty that the List #3910 & #3911 carbs were identical as far as certain drilled orifice dia's are concerned, but whether this is true or not is unknown to me at this time.

The primary metering block used on the List #3911 carb is stamped with the ident no.: 5462 on its top surface.  Does anyone have one of these 5462 metering blocks they would allow me to measure various hole dia's, or agree to let me send various size numbered drill bits to you for you to measure these few holes?

Maybe someone out there has a List #3911 main body that would yield the air bleed hole dia's?

Thanks for your help.  It is still my desire to have the CRG publish the data on the website when it is completed.

Again, if anyone with a List #4053 carb (used on all '68 & '69 Z28's) would like to confirm the dia's of any tuning holes in their carb have been drilled out or not, please send me a PM and I will respond.

Chuck B.

My '69 Z28 was 'born' with a 4.88 axle ratio via COPO 9511CB, and therefore has the required 90 degree speedo ratio adapter, used only on 4.56 and 4.88 axle cars, in place on its original Muncie M22 trans.  My speedo cable acts like it might be starting to fail (intermittent speedometer needle vibrations).  This condition has been helped by pulling out and re-lubing the cable's inner drive core with distributor point cam lube but experience tells me this is a temporary fix.  I'd like to find the correct replacement speedo cable to purchase.  I'd also like to confirm if Z28s like mine (4.56 & 4.88 axles) with a speedo ratio adapter did or did not use any speedo cable support clips in the tunnel sheet metal.  My car has only one cable supporting clip hole in the tunnel area (not the two clip holes some have reported seeing on their car's tunnel) but there is no clip in that hole.

Would appreciate help with the following:

1. Was a speedo cable support clip(s) not used on 4.56 & 4.88 axle cars with the required 90 degree speedo ratio adapter?

2. Did 1969 Z28s originally equipped with the speedo ratio adapter use the same speedo cable length as Z28s with the 4.10 or 'taller' axles that didn't require the speedo ratio adapter?

3. If the answer to question 2 is Yes, is the 71" speedo cable offered by various parts suppliers the correct length for all 1969 cars with the Muncie 4-sp trans?  If the answer is No, would anyone know the correct length speedo cable for use with a speedo ratio adapter, and what source offers this length cable?

Thanks for helping.

Jeff,

It's been about 6 months since the last post on this topic and I was just wondering if you've purchased your new exhaust system. Did you go with an aluminized system from Gardner or the Heartbeat City system?  How do you like what you wound up with?  DId it install without issues?  Quality of parts good?

Thanks for any feedback you'd be willing to share -- I'm in the process of making the same decision for my '69 Z28.
Chuck

The possibility that it is the dealer stock number makes good sense.  I hadn't thought of that.  Thanks Byron.

Attached is a copy of my '69 Z28's Dealer Shipper.  The car is an 05E Norwood build I've owned since 1979, when I purchased it from the 1st owner.

Can anyone shed some light on the significance of the handwritten "#227" above the handwritten key codes at the bottom of the shipper?  Thanks a bunch.

I may be able to shed some light on this.  While I'm not familiar with this specific substitution of black phospated intake manifold bolts being used in place of the silver/zinc bolts on some small quantity of 1st Gen Z28's, I am well aware of situations in which an automotive manufacturing plant temporarily runs out of a specified part and has to use an alternate or substitute part to maintain production.  In the Big 3 auto company that I retired from after 30+ years, this was called a TSA, or Temporary Substitution Allowance, and required a buy-off from Engineering.  In fact, fasteners were the most common parts for which TSA's were approved by Engineering to keep the line running while Production Control scrambled to bring in the originally specified part.  In some TSA situations, the plant had to perform an additional activity or rework in order to make the substitution acceptable.  In the case of the black phosphated intake manifold bolts being substituted for silver/zinc bolts on Z28 intakes, it is quite feasible that the Flint Engine Plant may have been told that the swap was acceptable provided they applied silver paint to the bolt heads before the engine was shipped.  In this case, the issue was strictly appearance, not function.  TSA's, or the use of Alternate Parts were, and are today, a fact of life in any automotive manufacturing facility.

My current Camaro project has been to pull together a database of all of the specifications that affect the calibration on the OEM Holley 780 carbs that Chevrolet used on the 1967-'69 Z28 302 engines, Holley List No.'s 3910, 3911 and 4053.  The database includes many key features that were never published by Holley in their Numerical Listings or by Chevrolet in their Service and Overhaul Manuals or in any of the Holley Rebuild/Tuning books out there.  This would include various calibration features Holley incorporated in each of the specific carb bodies and metering blocks for these three List No. carbs, such as: PVCR hole diameters, Idle Feed Restriction hole diameters, Idle and High Speed Air Bleed hole diameters, etc. etc.
 
The purpose for pulling this data together is to act as a definitive source that would allow owners of these early Z28 carbs to determine if their particular carb has been modified from the OEM calibration condition by virtue of a previous owner who may have gotten a little overzealous with a drill and "attacked" one or more air/fuel calibration passages in either the metering block or the main body.  I am hoping the CRG Moderator will consider posting the database, when complete, in the appropriate section on the website, as a supplement to the very helpful Holley four-barrel carb info already posted there.
 
The database is 100% complete for the List 4053 Holley, used on all '68 and '69 Z28's sold in all 50 states.  This carb was the "easy" one to do, since I own an unmolested 4053 carb.
 
However, in order to complete the database (which has become a labor of love), I could use some help from owners of unmolested 1967 Z28 Holleys: either the List 3910 carb (used on all non-California sold cars) or the List 3911 carb (used on all A.I.R. system equipped cars sold in California).  I'm hoping to find a willing soul or two who would agree to work with me, and who ideally also owns a set of small number drill bits, to carefully probe a few specific drilled holes in their metering blocks and/or main body.  To access many of these calibration holes (PVCR, Idle Feed Restriction, Emulsion Well Bleeds, Main Well Siphon Break) it will require removing the fuel bowls and metering blocks from the main body.
 
If anyone steps forward to lend a hand in this endeavor (and who has access to a set of numbered drill bits or small gauge pins covering the range from 0.020" - 0.070" dia.), I will walk you through what would be involved in gathering the missing data needed to complete the database for their specific List No. carb.  In the event a volunteer steps forward but does not have access to these small drill bits or gauge pin sets, I will mail/loan you my set to use,  although the #1-60 and #61-80 sets are very reasonable (< $30) to purchase via mail order).
 
I've been in contact with many sources to date to get the database to the point where it is today.  This includes Engineers/Techs at Holley, knowledgeable Holley people at various Holley restoration facilities, and many others.  Recently, I've been in touch with Jerry MacNeish, a long time CRG Member, who is all for completing this database as it will be of significant help to 1st Gen Z28 owners hoping to accurately restore/return their carb back to the calibration it had when it left Holley.  Who can argue with that endorsement?
 
Until such time as the database for all three carbs is complete and (hopefully) published on the CRG website, if anyone who has a List 4053 Holley on their '68 or '69 Z28 and would like to know what the original hole diameter should be of any of the metering block or main body calibration holes, just send me a private message and I will gladly help you out in any way I can.
 
Thanks for reading and many thanks in advance to anyone who volunteers themself and their carb to help complete this database.  I'm posting this in the "Originality" category as well.
 
Chuck B.

My current Camaro project has been to pull together a database of all of the specifications that affect the calibration on the OEM Holley 780 carbs that Chevrolet used on the 1967-'69 Z28 302 engines, Holley List No.'s 3910, 3911 and 4053.  The database includes many key features that were never published by Holley in their Numerical Listings or by Chevrolet in their Service and Overhaul Manuals or in any of the Holley Rebuild/Tuning books out there.  This would include various calibration features Holley incorporated in each of the specific carb bodies and metering blocks for these three List No. carbs, such as: PVCR hole diameters, Idle Feed Restriction hole diameters, Idle and High Speed Air Bleed hole diameters, etc. etc.
 
The purpose for pulling this data together is to act as a definitive source that would allow owners of these early Z28 carbs to determine if their particular carb has been modified from the OEM calibration condition by virtue of a previous owner who may have gotten a little overzealous with a drill and "attacked" one or more air/fuel calibration passages in either the metering block or the main body.  I am hoping the CRG Moderator will consider posting the database, when complete, in the appropriate section on the website, as a supplement to the very helpful Holley four-barrel carb info already posted there.
 
The database is 100% complete for the List 4053 Holley, used on all '68 and '69 Z28's sold in all 50 states.  This carb was the "easy" one to do, since I own an unmolested 4053 carb.
 
However, in order to complete the database (which has become a labor of love), I could use some help from owners of unmolested 1967 Z28 Holleys: either the List 3910 carb (used on all non-California sold cars) or the List 3911 carb (used on all A.I.R. system equipped cars sold in California).  I'm hoping to find a willing soul or two who would agree to work with me, and who ideally also owns a set of small number drill bits, to carefully probe a few specific drilled holes in their metering blocks and/or main body.  To access many of these calibration holes (PVCR, Idle Feed Restriction, Emulsion Well Bleeds, Main Well Siphon Break) it will require removing the fuel bowls and metering blocks from the main body.
 
If anyone steps forward to lend a hand in this endeavor (and who has access to a set of numbered drill bits or small gauge pins covering the range from 0.020" - 0.070" dia.), I will walk you through what would be involved in gathering the missing data needed to complete the database for their specific List No. carb.  In the event a volunteer steps forward but does not have access to these small drill bits or gauge pin sets, I will mail/loan you my set to use,  although the #1-60 and #61-80 sets are very reasonable (< $30) to purchase via mail order).
 
I've been in contact with many sources to date to get the database to the point where it is today.  This includes Engineers/Techs at Holley, knowledgeable Holley people at various Holley restoration facilities, and many others.  Recently, I've been in touch with Jerry MacNeish, a long time CRG Member, who is all for completing this database as it will be of significant help to 1st Gen Z28 owners hoping to accurately restore/return their carb back to the calibration it had when it left Holley.  Who can argue with that endorsement?
 
Until such time as the database for all three carbs is complete and (hopefully) published on the CRG website, if anyone who has a List 4053 Holley on their '68 or '69 Z28 and would like to know what the original hole diameter should be of any of the metering block or main body calibration holes, just send me a private message and I will gladly help you out in any way I can.
 
Thanks for reading and many thanks in advance to anyone who volunteers themself and their carb to help complete this database.  I'm posting this in the "Restoration" category as well.
 
Chuck B.

Thanks, Jim -- great info.  I'll give your method a try.

The COPO 9511 code was used in 1969 to specify either a 4.56 axle ratio (via 9511DT) or a 4.88 axle ratio (via 9511CB).  Without utilizing this code, the highest numerical RPO axle ratio available in 1969 was 4.10, unlike the '67 and '68 cars which anyone could order with a 4.56 or 4.88 ratio as an RPO.  I would think there were fewer 4.56/4.88 builds in '69 (vs. '67 or '68) due to those ratios no longer being an RPO -- just my guess.


Has any new information surfaced in the past decade or so that sheds light on the number or percentage of 1969 cars in the general population of all Camaros, or just the Z28's, SS's or COPO 427's, that were ordered under COPO 9511?

The plastic lens on each front park/turn lamp on my '69 have become stuck in place and are resisting removal.  In my 46 years of owning the car, neither lens has been removed.  I'd like to inspect the bulb and socket in each but I have not been able to remove the lens from either lamp assembly.  The three screws back out just fine but the lens/gasket/housing are all apparently stuck to each other.  I'm hesitant to apply any more force with a flat screwdriver than I have already tried, in fear of cracking the lens.  Has anyone had success in applying WD-40 or some other fluid around the perimeter of the lens, or found another method to help to "unstick" the lens, without staining or damaging the lens or housing?


Thanks for help on this "sticky" situation.