ZL1 canam block help

Hi guys I have a very early ZL1 alloy block which judging by the research i have done is an experimental block supplied to a canam team.
I wondered if anybody might have further info on the block or be able to interpret the markings in the pictures I think the 155/ 06 mark might identify the team? . Any help would be greatly appreciated thanks in advance Mark
 

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Rick Muck- Mark IV

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The first blocks were cast by Reynolds Metals (Massena NY foundry I believe), the later blocks were cast at the Chevrolet Tonawanda Engine Plant (a friends father was one of the casting guys there and told us about doing a "special job" with all sorts of GM engineers in attendance).

As I recall the first blocks all went to McLaren and Penske. I would assume the casting number would relate to the consecutive casting order (batch/production order) but could be wrong.
 
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First blocks were sleeved ( like yours ) later were linerless with coated piston skirts ( as per vega tech of that era ) and known as the Reynolds block ( not sure if that fits into Ricks time frame ) and later GM production was ZL-1.
 
Mark,
I looked at your block and it seems a bit of a mystery to me. The early CanAm blocks had no mechanical fuel pump bosses and was sleeved 4.44 bore 4 bolt main. The 0-326711 is the Chev Engineering number and the casting look's like Saginaw Service (S) so I think it is a later block like Jac Mac said and someone was trying to add sleeves to it later.
Dave
 

Sandy

Gulf GT40
Lifetime Supporter
I have something that was told to be a similar Chevy CanAm block. It is in my 427 (well 468) Cobra now, but it has been polished and missing all the numbers. I have had it around 10 years and I got it from a guy that got it from another guy. I think another fellow said that it may be the same castings but done post the CanAm Chevy block era by somene besides Chevy (all fuzzy). My block does have sleeves and a boss for the mech. pump. I think you can see some photos in the CHEVROLET POWER BOOK from many years ago that list all the various combination, Lined, Unlined, destroked with 348/409 cranks. I think also the oiling system over the filter area may be slightly different the the 4 Bolt BBC's but not sure.

I think it may have one casting number over the bellhousing boss and I'll look and see if I can see it, but NO GM/Winters Snowflake or anything left after whoever owned it polished it.

http://www.gtsparkplugs.com/VSECobra.html scroll down and you can see some fuzzy pics on the dyno and stuff in the car.

While the car was at VSE in Carmel Ca, a guy came over and flipped when he saw the block and said it was a CanAm block as he was right in the midst of a restore of a vintage CanAm car (McLaren?). Again, not sure if he really knows or not but he mentioned the oil taps at the top of the filter house as being unique. I offered it up in trade for an alloy SBF as 700hp in the VSE is out of whack even for me, but he was car rich and cash poor. So in it stays.

BTW I also have somewhere a new ZL1 Mech Cam from Chevy I bought years ago from some Chevy dealer that still stocked them, just never had the heart to use it.

Chevy did re-release the ZL-1 a year or so back as they had them at Jegs and I thought that was hot but when all said and done could do better with a Donavan block and doing it my way. Then a few months ago again the 'never seen before release' of the ZL-1 announced (sarcastic). I think it is a low compression hydro-roller version but still nice 'crate' package.

Here's a link to the new one with some specs -

Motorator Blog - GM's Limited Edition 427 Crate Engine.

Sandy
 
Sandy,
He has a GM casting. It may be a later one of the ZL-1 era. I am pretty sure it is Saginaw Service, it would be casting 6 of 155 run done on shift II when I do not know. They did not date stamp it (usually a clock in the casting for time) I would rather have a later one. Some of the earlier blocks had overheating and sealing problems. The one thing with service parts is back then is they did not get the same attention as production parts. Everthing is computerized now and better records kept.
Dave
Engine Assembly Plant Codes
F- Flint Motor
H- Hydramatic
K- St. Catherines (Mckinnon)
S- Saginaw Service
T- Tonawanda
V- Flint Engine
 
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Based on what I have found:

O-326711 would make this a Can-Am block circa 68/69. 4.44" bore with steel liners
(427 ci).

If it were a later Can-Am block, circa 70-71, it would be O-399204 with 4.5" bore
and steel liners (509 ci) or O-495102 with 4.5" bore and no liners.

ZL-1 factory optioned blocks would be stamped 3946052, no "O".

Are there any stampings on the engine pad around where the heads would attach?
An oval with "Traco" in it, and/or "L.M. 427" or similar?

Try contacting Wayne Guinn at Guinn's Engineering:

Guinns Engineering Camaro Services

He has done similar research on another Can-Am block.

Ian
 
Definitely NOT a 'Reynolds' block, they dont have several of the 'bosses' in the valley that your pics show and are cast differently in the LR corner around #7 cyl.
 
Jac Mac,
I agree with you the casting signature would have a box or shield with an R in the center for a Reynolds foundry casting. There was no provision for mechanical fuel pump on the original Canam Reynolds cast blocks. The "0-" before the part number is Chevrolet Engineering desination it's just a later ZL1.
Dave
 
The "O" casting number indicates a prototype/interim casting/part number.
Production numbers had no "O" and had 7 digits as opposed to "O" and
6 digits.

The aluminum Can Am prototype was supposedly available over the
counter, but public access was limited so that supplies were sent to
race shops.

The last prototype Can Am engines, just before ZL-1 production started,
did have bosses for mechanical injection.

Again, I would contact Wayne Guinn - he tracks this stuff down for
historic purposes. He has documented a similar Can Am block before.

Ian
 

Sandy

Gulf GT40
Lifetime Supporter
Interesting stuff. I'm going to look around at my motor and see if it has any of the casting marks again. Always wondered what I have. The block I have did have an internal oil leak to the water jacket which was fixed (I hope). All good info.
 
Guys thanks so much for the info keep it coming!!! I have tried to contact Guinns Engineering on a few occasions and sent pictures hoping to use their paid for part verification service but they have not replied to my emails. Perhaps I should try ringing it is just getting the timing right from the UK :)
 
thanks for all the feedback guys I got an email reply off Wayne Guinn will give him a ring and hopefully find out more.
 
Re: ZL1 Can Am block help

Hello everyone. I am new to this forum but it appears to be a very good one for info. My name is Rex Turner and I am from Kentucky in the USA. I too have one of these Can Am alum blocks and am hopeful that someone here can help me identify it and perhaps some of its history.

Here is a brief description of what I have:

My block is a wet sump block, no boss for mechanical fuel pump. I have a prototype alum water pump and a cast alum front timing cover with and integral crank-driven oil pump. Casting number on the rear of my block is 0-321270, and cast date in lifter valley is Feb 1968. It was cracked in the water jacket and I have sent it out for repair.

I spoke with a retired GM engineer and Jim Hall (Chaparral Race Cars), and both confirmed that it was a Can Am block, but could not identify where it was used. It has the 4.440 liners in it. I have a new LA Enterprises 4 inch stroke crank and a set of Carrillo rods and Ross flat top pistons that I plan to use along with a set of 391984 closed chamber alum heads. Plans are to use the engine in my street-driven 68 Corvette clone race car.

I would like to have a neat induction system such as a Weber crossram or
Kinsler fuel inj unit like John Greenwood used on his race cars.

I have spoken with Wayne Guinn several times and he seems more interested in documenting my NOS magnesium valve covers and twin pickup oli pump than the block.

Any help or info that anyone can provide will be much appreciated. I am located in Kentucky.

Thanks,
Rex
 
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Rex,
It sounds like you have one of the earlier blocks. Look for the Renolds casting mark. It could be a knight on a horse or an "R" or an "R" in a shield. It would from the Massena NY foundry if it's there. An other possibility would be to look for a DUNS number it could be cast in the block or hand stamped. These numbers identified suppliers for GM for material purposes. It was a bit before my time with GM. But the system was the same when I started. It was a way of tracking parts and vendors. Usualy the rack they came on had the part number along with the DUNS number this way they could send the racks back to the proper vendor.
Dave
 
Hi Dave and thanks for your reply. The block does NOT have a Winters foundry mark on it. There are some numbers / letters stamped as follows:

RMC M2
{stamped on the left rear of the block just above bellhousing
T7


2454 {stamped into front on pass side to left of timing cover


C1 {stamped into front of block just behind timing chain

What are your thoughts on these?

Thanks in advance for your help.
Rex
 
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