Holley Prep for Dichromateing

[1967 XR7 GT]

When I was going to have my carb colored I asked about prep, was told it needed to be clean, degreased, or there would be a cleaning charge, so I had it vapor blasted.

Warning: Do not Vapor Blast Holley Carburators.

Dichromateing after VaporBlasting, provides very poor results. The Dichromateing comes out a dull, flat colorless, lacking any Iridescence, crap job.

You can ask how I know.  It might have been ok? if I had prept it, wire wheel, wire brush, scotchbright, just something removing the Vapor Blasting surface results.   

I, provided a couple of pics of the carb I had done, as can be seen it's just a flat green color, will try later to provide a better complete pic of the carb.

[Drew Pojedinec]

There is a whole 300 page book that I could write about this.


Why are you certain that variable was the issue?

[RJP]

The cat doesn't like it either.

[1967 XR7 GT]

There is a whole 300 page book that I could write about this.


Why are you certain that variable was the issue?

My carb is a Holley 1030 cfm 3 barrel. The guy who did the coloring had me wait after he received my carb, he wanted to wait till he had enough carbs to do a run. I guess he didn't like to color one at a time.

He had said my carb was the only one the coloring turned out this way out of the run, and was the only one vapor blasted.

I had my intake vapor blasted before my carb, and the finish is different, including the feel and even the look which is a flat dull aluminum, which is exactly how the coloring came out

[Drew Pojedinec]

I just did this one.
Wet blasting isn’t the cause of your issue.

https://www.facebook.com/share/1JoPJyntVR/?

Who did the work?

[1967 XR7 GT]

I just did this one.
Wet blasting isn’t the cause of your issue.

https://www.facebook.com/share/1JoPJyntVR/?

Who did the work?

I have his card somewhere, It was someone you recommended, I had asked you 1st but you didn't have time, said you were backed up and had to go back to work, the carb work were side jobs when you were home ? This was a while ago.

I sent it to be colored, have the vent tubes pulled, and drill & tap the main body air bleeds for screw in bleeds.

I looked at your link of your colored carb, I assume the carb you pictured at the end was the carb before the color, it had a metering plate on the 2ndary side, which is a problem, which I am sure your aware of, the air bleeds on a 3 barrel 2ndary are in a different location so a stock metering plate won't work correctly, if that carb ran that way it had big problems, and could never have been tuned, or at least not the 2ndary side.

I was playing around modifying a metering plate to work on the 2ndary side to beable to run 4 corner idles, don't remember if I finished it but was close. But I did get the aftermaket metering plate for 4160 carbs for the 3 barrel 2ndarys to add jets just in case.

[Drew Pojedinec]

Only a few people do partial jobs.
I’m not one of them at this time.

My point was, the wet blasting didn’t cause the issue.


And yes, that is why I told the customer I would not use a metering block.

[1967 XR7 GT]

I did some research, what I had done was called "Vapor Honing", there is also "Vapor Blasting" "Wet Blasting,"  and "Dustless Blasting" these processes are all different.

So, I need to up date my warning: Do not do Vapor Honing to your Holley Carb before  coloring. As to Vapor, Wet, and Dustless Blasting, you'll have to do your own research as to  the coloring results after, I've not used those processes so I don't know their results.

My Intake Manifold I had used Vapor Honing not Vapor Blasting, and I now remember I had Vapor Honing done to protect the Manifold, as was demostrated to me I took dirty grease and wiped a spot on the Manifold, then wiped it off with a rag, no discoloring, stain or any indication that grease had been on the manifold. If grease had been wiped on a Manifold that had been bead or sand blasted, there would be a stain where it was applied.
 

[Drew Pojedinec]

Richard, wet blasting is a process.
Vapor honing is a specific manufacturer.

Kinda like Kleenex is a name for all tissues.


In this case the blaster either used really coarse media or the carb sat too long and oxidized, both can cause your issues.

I tried to clear this up as I don’t care for misinformation.
Good luck.

[pbf777]

. . . . . . . dull, flat colorless, lacking any Iridescence, crap job.

. . . . . .  as can be seen it's just a flat green color, will try later to provide a better complete pic of the carb.

     Though the coloration of your carburetor might not be what you were hoping for, it actually isn't unlike that of what many having come out of Holley looked like, "originally".  The finish as delivered by Holley wasn't very consistent, and the individual componentry items were often different in coloring, and this only became more so as the decades progressed.   

      And with this observation,  I'm of the opinion that some of the quite bright finishes as being executed today of "refinished/restored" examples as has become expected, being required in the industry to provide the impression of a quality execution, but is not representative of mostly that as which Holley provided , back then.      

      Scott.

[Drew Pojedinec]

Scott, I agree with you 100% on post 1967 carbs.
Post 67, quality control and outside vendor usage fluctuated a lot more.
I kinda went down this rabbit hole some time ago lol.

I have studied the original earlier carbs extensively and find my chromate matches what is seen in the originals (once it calms down after a year or two).
The pictures I post are typically right after the coating is applied. I save some restored parts for years to see how it ages. Once it mellows down my stuff gets darker and less blingy.
I’ve shown nos stuff vs some of mine a few years later and it isn’t that far off.

That said, my personal view is any coating is original once…..  after that it is just going to be different. I wasn’t at the Holley factory in 1964, nor was anyone else I know, so we are just throwing darts blindfolded anyhow.

[1967 XR7 GT]

Richard, wet blasting is a process.
Vapor honing is a specific manufacturer.

Kinda like Kleenex is a name for all tissues.


In this case the blaster either used really coarse media or the carb sat too long and oxidized, both can cause your issues.

I tried to clear this up as I don’t care for misinformation.
Good luck.

Vapor honing and vapor blasting are often used interchangeably, but they have subtle differences. Vapor honing typically involves a higher water-to-abrasive ratio, resulting in a gentler finish, while vapor blasting may use a more abrasive approach for tougher materials.

As I said before, my carb was done in a batch of carbs by my carb guy, the other carbs he put thru his cleaning process which was - a 2 stage bead blast. Medium grit with high pressure, then fine glass bead with low pressure, my carb was not put thru this process because everything was already clean from the Vapor Honing. Out of all the carbs he colored that day mine was the only one that came out as it did.

The issue I had, the carb guy never notified me of the coloring issue, he just sent my carb back the way it was.

I've provided no misinformation, only facts.

But, Drew since your so experienced and know it all, I've got nothing more to say.

[1967 XR7 GT]

. . . . . . . dull, flat colorless, lacking any Iridescence, crap job.

. . . . . .  as can be seen it's just a flat green color, will try later to provide a better complete pic of the carb.

     Though the coloration of your carburetor might not be what you were hoping for, it actually isn't unlike that of what many having come out of Holley looked like, "originally".  The finish as delivered by Holley wasn't very consistent, and the individual componentry items were often different in coloring, and this only became more so as the decades progressed.   

      And with this observation,  I'm of the opinion that some of the quite bright finishes as being executed today of "refinished/restored" examples as has become expected, being required in the industry to provide the impression of a quality execution, but is not representative of mostly that as which Holley provided , back then.      

      Scott.

Here is an example of color from back then, it's my NOS Holley 4604-S 1050 CFM 3 Barrel, the color has faded some I would think since the late sixties code 973 Year 1969, month 7, in the 3 week, over 50 years.

[Drew Pojedinec]

Well, I was gonna make an offer to deal with it.
Seems a bad idea now.

Good luck sir.

[1967 XR7 GT]

And yes, that is why I told the customer I would not use a metering block.

For the gentlemans sake since he's spent some money on his carb, and would like for him to be able to use the carb, (or anyone else who has who either has a 950 or 1050 cfm 3 barrel and wants to run them,) and as long as his carb has the correct primary metering plate #5615, if it hasn't had the PVCR modified yet, that would mean the PVCR are currently at .040" which will cause primary tuning issues, such as a bog, then he'll up the jets then it will run pig rich, he will need to open the PVCRs up to .070" the same as the 850 DP which come with .070" PVCRs, which basicly what the primary side of the 3 barrel is.

Basically, with the corrected PVCR you would tune the primary side of a 3 barrel holley the same as you would a 850 DP.

In 66-67 when these carbs came back out, they were tuned for smog, thats why the .040" PVCRs. The 1st 3 barrels came out in 64, Chrysler had the them made for the Nascar HEMI, I don't know if they were 950 cfm or 1050 cfm I've never seen one so don't know what size they were, but had no unusual tuning issues, the primary metering blocks on those were #4328, and I have one I picked up off Ebay and those have a .093" PVCR, the larger PVCRs were needed due to the restriction caused by the emulsion tubes in the main well reducing fuel flow, which I am able to see the end thru the channel restriction.

1st pic is of a 5615 metering block, with a .040"pvcr.
2nd pic is of a 4328 metering block, with a .093"pvcr