1969 z/28 intake bolts

[john302]

The intake bolts are black phosphated and painted silver after installation . The 1100 miles 1970 z/28 is a great example. They were probably brushed silver . The question is are the rear bolts for the sparkplug stands painted too? the center bolt that holds the vacccum advance tube painted ? sprayed ? brushed ? i have seen the spark plug wire stands brushed orange in the past . Thoughts ? maybe Lloyd or Steve S will chime in ? Thanks

[firstgenaddict]

The stands are brushed orange and the intakes have silver paint brushed on around the ends... on my LT1 the paint on the drivers side rear is running down the back of the head.

First pic is of a may 69 Z28 with the paint pooled up

Next pics of my LT1.

[Edgemontvillage]

John, although Charlie's (former) 1,100 mile 1970 Z/28 is an excellent reference, not all the 1970 MY assembly line processes and finishes were the same for 1969 production. Of the original 1969 Z/28s I've seen, the intake manifold bolts were plated clear (silver) zinc rather than phosphated. As zinc ages and succumbs to heat cycles, oxidation, fuel and oil deposits it may appear phosphated. I have seen manganese phosphated intake bolts on late production Z/28s. The front lift hook will have silver paint or orange on early cars with overbrush on the bolt. The wire stands were also brush painted and the bolts securing them will have orange overbrush paint. On Page 42 of the Legends Judging Manual, Intake Manifold section it states "Aluminum intakes use silver cad/zinc shouldered bolts for big blocks and non-shouldered for Z/28s." 

The original, never previously removed intake manifold from my 2B Norwood built RS Z/28. The intake bolt heads appear manganese phosphated however the threads were clear zinc plated when removed during disassembly.

[john302]

I agree on the brush painted stands and  the silver painted lift hooks . Not to sure on the silver plated intake bolts . I have done them silver zinc in the past on a 68z and 69z restoration . But have seen black plated bolts on survivor cars . More research ! The manual for the Legends Judging is good but not perfect . Wonder what the Corvette ncrs specs are on the L79s ?

[rszmjt]

The 6,000 mile 1970 LTI engine I have had for 25 years has black non flanged bolts, "M" head, and the threads are black, 1st time a intake bolt has ever been removed was today. You can see remnants of brushed on aluminum paint on bolt sides. The stand bolts appear natural.
 The lift brkts are natural BTW. Pretty sure my own 69 Z has black bolts to. Hope this helps.

Mike.

[john302]

Great photos . I checked what the Ncrs manual its black phosphate. Also checked with the 1966 L79 Nova expert and he said the same black phosphate . So if they were black in 66 and 70 i believe 69 would be too ?

[rszmjt]

Weird, The photo of the bolt is all distorted unless you open it in a new tab, I posted these from work computor and they were fine, anyone else have problems?

[firstgenaddict]

Weird, The photo of the bolt is all distorted unless you open it in a new tab, I posted these from work computor and they were fine, anyone else have problems?

The resizing program distorts the width and height, because it was shot in a vertical format the programs is distorting it into a horizontal format. IF you can modify your post and rotate the photo 90 deg prior to uploading it the distortion should take car of itself.

IF you right click on the image and open in a new tab the format changes to vertical and the distortion goes away.
Black zinc bolts with silver paint on them is correct -

[Dave69x33]

Regarding the lift hooks on small blocks built by the Flint Engine Plant, and specifically the '69 Z28 302 engines, where the lift hooks not installed during final engine assembly at Flint?

When the engine was painted orange, I understand that foam core mask were placed over the intake manifold and the aluminum valve covers, and a round mask was placed over the distributor.  I assume the lift hooks where natural steel finish and exposed to potential orange overspray while the engine was painted.  Does this make since? 

I believe this is why you see a number of 302 Z28 engines with the lift hooks painted complete and neat with orange rather than with orange overspray.

I know that some of the mask placed over the aluminum intakes must have been in bad shape, as I have seen unrestored intakes with a orange overspray on surfaces up towards carburetor mounting surface. It looked very sloppy.  The same applies to the distributors.  My distributor had considerable orange overspray on the base and on the bottom surface of the distributor housing.  The rear flange edge on one of my valve covers also had orange overspray.

So it is only my assumption that "originally" the lift hooks could have varying amounts of orange overspray on them. 

[Chill Air]

Lloyd,  Do you have a picture of that manifold showing the rear engine hook?