1969 Z28 Cross Ram Help???

[Lynn]

I had a GM cross ram top years ago, and can say with certainty that it did not fit the Offy or the Edelbrock bottom.

So.... are you saying the reproduction cross ram isn't the same bolt pattern as the GM? That would seem a major goof.

Also, don't the repros all have the same casting date? Anyone know that date?

[iluv69s]

First of all, the repo tops fit the GM bottoms. Second, the early prototype intakes all bolt up with the later tops and bottoms. The changes were minor once they started the 'production' intakes.

The bottom does not look GM to me off the top of my head. I see no bosses for the oil sheild mounting points that the early units had. These bosses were on all the intakes even though they cancelled the oil sheild. The top looks like a repo also. It is difficult from pics because the repos are pretty good. If you can post some closeups of the edges of the intake top and also the mating surface where the top mates to the bottom, I can tell you definitively. The machining marks are a giveaway between the new repros and the originals.
I can pull out one of my original intakes to compare. I also have an offy intake that ill look at to compare. I would bet that you have an Offy base..and a repo top.

[camaromb]

Repro crossram, missing lots of the details that original ones have.

[Tracker1]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: iluv69s</div><div class="ubbcode-body">First of all, the repo tops fit the GM bottoms. Second, the early prototype intakes all bolt up with the later tops and bottoms. The changes were minor once they started the 'production' intakes.

I would bet that you have an Offy base..and a repo top.

</div></div>

I'll take your money [img]<<GRAEMLIN_URL>>/smile.gif[/img] - an Offy base with a winters foundry marking and a GM casting #? Nope.

[Stefano]

I believe the Offenhouser has one less bolt securing the top to the base while the Edelbrock is a match to the GM X-Ram.

[iluv69s]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stefano</div><div class="ubbcode-body">I believe the Offenhouser has one less bolt securing the top to the base while the Edelbrock is a match to the GM X-Ram. </div></div>

Actually 2 less bolts

[Tracker1]

Ok I will send you a dozen Canadian beer in the mail [img]<<GRAEMLIN_URL>>/beers.gif[/img]

they will be real - not re-pops like this cross-ram [img]<<GRAEMLIN_URL>>/smile.gif[/img]

[iluv69s]

With all due respect, welders can do amazing things nowadays. Check Jerry M's sight
and you will see pics of the original block from my Zl-1 that had the snowflake ground off and 'put back on' by melting a piston and making a plug w the snowflake using another original block to make a mold. Than a hole was made using a holesaw and the plug welded back in... After a reskinning of the whole block the repair is unoticable.

I did pull out an original xram and a new offy unit that i had for years and took a look. I am 99.99% sure this base in question is not a GM base..nor a repro.. ( I also have a repo unit I bought a while back) ..

I am 99.5% sure it is an Offy base .. When compared w the pics of the base in question, the similarities are obvious compared to a GM unit.. Im traveling to brazil tomorrow, but i'll try to post a few pics...

Also the repo units are actually very detailed and excellent copies that are almost undistinguishable to an original..

Still wanna bet?? Just kidding !!

Max