ZL-1 block versus Can-Am block?

[DandyDon]

A hot rod acquaintance has a 1969-1970 vintage Aluminum BBC motor. He claims it came from Bill Jenkin's shop many years ago and has just been rebuilt. I assumed it was an over-the-counter ZL-1 block but he referred to it as a "Can-Am" block. Are these the same blocks? If not,what are the differences?
He said the Can-Am block was used by Jim Hall in the Chapparal program.
Any thoughts?

Thanks- DandyDon

Off hand, the Can Am block should have a larger bore (sleeve) size -- 4.440-inches versus 4.25-inches for the ZL1. The original Can Am engine was built with a short stroke (3.47...I think, but I'm getting old) for a final displacement of 430 cubic inches, but that changed quickly.....a 4.0-inch 454 crank produced a 494. And as we all know, there's "no replacement for displacement" <g>. IIRC there are other differences, but that's the big one.

Wayne

[PeteLeathersac]

Jenkins did run CanAm blocks...is there truth to where it came from?.
What's the casting #?.
Is there a provision in the block for a mechanical fuel pump?.
Lance 'midyr' on this site may be able to share some insight as he ran a few of these blocks back in the day and ended up w/ what was left of Geo. Eaton's CanAm stuff..


~ Pete

[John Brown]

I don't think the Can-Am blocks had any provisions to mount a fuel pump on the block either.

[Kim_Howie]

I don't think they have side motor mount bosses. From what I can remember on them.

[Kim_Howie]

The motor that was in my 70 Camaro was a Can Am motor. Dave libby told me that it was. The pictures taken in 1970 prove that. The block had no winters flake on it and has a fuel pump where the fuel pump mounting boss is.

[John Brown]

From CRG.... http://www.camaros.org/copo.shtml talking about ZL1 production engines vs Can Am engines.

[ QUOTE ]
In production form, the engine differed from Can-Am configuration. The dry-sump oil passage was eliminated and provision for a mechanical fuel pump added. Production tooling was developed for the block (castings #3946052/53), cylinder heads (#3946074), and intake manifold (#3933198). A new aluminum water pump was to be included (and at least one and perhaps two Camaros were built with it), but last minute testing raised reliability questions.

Chevrolet continued to develop the Can-Am version of the aluminum big block for racing, progressing to a liner-less 390-alloy block buildable in displacements of 430, 441, 494 and 510 cubic inches. These did not have provision for a mechanical fuel pump. They were never used in production and few were produced.

[/ QUOTE ]

[PeteLeathersac]

Here's the block casting #'s and info I've collected..
Please feel free to add the missing & more info also clarify and/or correct any mistakes..


Can-Am blocks 68/69 - Reynolds
# 0-294550 = Linerless?
# 0-321270 = Linerless?
# O-326711 = 4.44" bore with steel liners (427 ci)

Can-Am blocks 70/71 - Reynolds?.
# O-399204 = 4.5" bore and steel liners (509 ci)
# O-495102 = 4.5" bore and no liners

ZL-1 Factory blocks - 1969 - Winters
# 3946052 (No 'O') 427 ci.

ZL-1 Factory blocks - 1997 & up
# 3946053 (No 'O') 427 ci.

# 3992038 (O?) * may be 4.44" bore w/ Liners - era?.

# ? - Yenko - Casting has YENKO
# ? - Yenko - Casting has Y E N K O
# ? - Yenko - Casting has Yenko Crest Logo

# 3946502 is the # quoted on the Guinn's Engineering site but the # is actually 3946052 as shown in their pics..


~ Pete

--------------------
I like real cars best...especially the REAL real ones!

[Kim_Howie]

Here is a pic taken by Jon Asher in 1971. please note no winters flake & fuel pump boss.

[Charley Lillard]

What's this ?