AMA passenger car specificatins - 1969 z28 "Locked in rod" piston pins

[69er]

Thanks for that valuable document. I have forwarded that document to General Motors to be included in the next revision of the "AMA passenger car specifications".

[69er]

This is a great discussion, passionate topic. I respect your written and signed affidavit.
Since my last post I decided to call several machine shops from California to New York. I chose
machine shops that have been in business 25 to 35 years or more and machine shops that had
senior engine builders/owners.

I have listed six machine shops below that I called and asked if they have ever rebuilt 1969 Z28's 302 engines. And then asked if they could tell me how the piston pin was attached to the connecting rod from the "FACTORY". The key word here is from the "FACTORY".

All of the engine re-builders responded that the piston pin was of "PRESSED PIN" design.

From what they said,  the L88 was the only engine that came with full floating piston pins from the
"FACTORY".

I find it hard to believe that all these machine shops would be conspiring in some way. They as well are enthusiast and love what they do and are equally as passionate.

I started this thread due to another member posting the AMA passenger car specifications. I have no axe to grind or want to discredit anyone in any way or manner. Now after speaking with at least six machine shops and engine re-builders from West coast to East coast. I feel even stronger now that the connecting rods from the "FACTORY" on the 1969 Z28 302 were of "PRESSED PIN" design.

I urge any member to call machine shops in their own area and ask the same questions I did and draw their own conclusions. I think the moderator of the CRG should do research as well and see where the facts point. And when enough information has been gathered, post it for all to read.

Below is the list of machine shops I contacted. Company name , telephone number, name of engine re-builder and their comments are listed.

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McQuillen Inc.
8171 East Main Road
Le Roy, NY 14482
1(585) 768-2322

Rebuilt bunch of 1969 z28 302 engines all were pressed pin design.
L88 was only engine factory made with full floating piston pins

Mr. Carl McQuillen - Engine builder
carl@mcquilleninc.com
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Performance Engine
1-310-679-3604

Tony - Engine builder
Rebuild hand full 1969 DZ - all were pressed pin design
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Al Hubbard Machine Shop (Been around since 1960's or before)
21030 Meekland Ave
Hayward, CA 94541
1 (510) 537-1885

Wade - Engine builder
rebuilt 2 to 3 1969 DZ - all were pressed pin

Never seen a "FACTORY" 69 z28 with full floating pins for the connecting rods
and has never seen any small block from the factory with full floating piston pins.

Big Blocks, yes, but not small blocks.

Maybe specialty builds had full floating piston pins not service engines.
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Champion Performance LLC
24290 Sherwood Ave
Center Line, MI 48015
1(586) 755-7400

Mr. Ed. MIchaels - Engine builder
Rebuilt half a dozen dz engines - all were pressed pin
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Coast Motor supply
1-818-703-9049

Omar - Engine builder
Rebuilt half a dozen 1969 DZ - all were pressed pin design
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Pro Formance Specialties
1115 East Main Street
Rochester, New York
1-585-288-1499

Spoke to engine builder with many years of experience
Rebuilt several 1969 z28 302 engines - all were pressed pin design.
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[69Z28-RS]

Everyone, including 69er, is free to *believe* what they want ....

After reading all you've written here, and also finding a thread from 2006 (started by ASM69 - and you both sound a LOT alike - new user name for you??)..  It seems to me to be so..
Here's the old thread with all the evidence you were presented then:
http://www.camaros.org/forum/index.php?topic=1015.0

Additionally, here is my own 'evidence'...

1) I rebuilt my original (never have been disassembled before) 302 from my '69 Z28 in 1976.  It had, and has, fully floated piston pins.  I have the original rods and original pistons that I could provide photographs for you if you'd like to make a wager?? 

2)  I do recall, when I rebuilt my engine in 1976 it was not uncommon for machinists to *recommend* doing 'fixed' pins in the pistons, but my friend (Robert a Christiansen) who had purchased his own 69 Z28 new in Dec '68, and who was assisting me in rebuilding my 302, told me that there was nothing wrong with the floating pins and I should so that, so I did (with new 30 over pistons).  He had raced his '69 Z28 in SCCA/TransAm, and also in IMSA GT from '69 thru the early 70's.

Bob (Robert) is still alive, and I have another friend who bought another '69 z28 and raced it in SCCA and TransAM/IMSA Gt also.  Both of these fellas are engineers and have excellent memories.  I will inquire with them both.

You said these guys you checked with were 'in business for 25 to 35 yrs; Do you realize that '69 Z28's were built 47-48 yrs ago??  and that most were *already rebuilt* within the first 10 yrs of their lives!  Maybe none of them EVER disassembled a factory original 302.

I'm curious... WHY are you so determined to try to convince people who know better, that the '69 302 piston pins were *pressed*

[bcmiller]

They were full floating pins starting about July of 68 (very late 68 model year) and for the entire 69 model year. The AMA document is not correct. End of story.

I have seen the inside of enough 302s to know, and have talked to numerous machinists over the years - most who have now been retired 5-10 years.

But believe what you want.

[z28z11]

I've got your proof if I can figure out how to post it - pdf @ 225kb, I can't determine out how to downsize it.

Piston/rod assembly removed yesterday from a February standard bore DZ, factory Spiralocs intact. They are pretty difficult to remove, so you'll have to wait a bit for pics of the small end until we can pull the Spiralocs and get a good pic of the pin bores.

Anyone have a tip on downsizing a pdf ?

Regards,
Steve

[z28z11]

Thanks to Darrell for massaging the two pics. One is less distinct than the other, but you can see the Spiraloc in place in the piston pin bore.

No doubts from me as to the originality of floaters in '69 302's -

Regards,
Steve

[KurtS]

And I thank you all for having a civil discussion on the topic.
On some other forums, the thread would have gone up in flames long ago....