Original Cobra coolant tank?
 

Hi:

I'm rebuilding an original 1955 AC Aceca that was partially converted to a V8 long ago. With the car, I got a brass coolant overflow tank that is marked on top "Bk-3266 Mc 5C4". It looks to me just like the design I see on many replicas, except that the top of the replica tanks I see in photos is ribbed; this one is not ribbed. I also got the mounting bracket with it. I want to know if it is an original Cobra tank or a knock off. I have two good photos I (hope) I've attached.

Can anyone help answer my question?

Thanks!

It's a McCord expansion tank for a small block Cobra. Looks to be an original though I can't see the side where the hose barb is.
Larry

427 Cobras used their own unique tank assembly in a very different set of characteristics and they had "ribbed" tops. 427 Cobra style tanks have been made by more than one supplier for decades. Cobra / McCord style replacement tanks have been made by at least two companies.

Looks like a genuine one for 4V induction cars; S1CS 8080 Surge-Tank, Cobra BM3266. (A Shelby American assembly apparently made up of semi-complete parts supplied by McCord was used for cars with optional 2-4V induction January 1964 onward; S1CR 8079 Header-Tank, Dual Quad.) The date is C4, which was March 1964.

BM 3266 = McCord's identification number. The corresponding radiator was BM 3265.
MC = McCord
5 = Unknown for sure but could be the identification of which McCord plant made the assembly, "5" is the only code I have in my collected database.
C = March
4 = 1964

One known 4V car prototype was made in very early 1963. (If there were others I have not found evidence of them.) There was at least one run of service replacement 4V car tanks made in 1966.

Evidence suggests that CSX2141 was the chassis that introduced the 4V Ford / McCord expansion tanks and radiators into production.


Technical Tip: Depending on what exact rocker arm covers used and tolerances in play for the left side cylinder head casting, the intake manifold casting you have, and some machining details spacers might be required to prevent the mounting bracket from interfering with the left front corner of the intake manifold and or the front edge of the left hand rocker arm cover. Not every original Cobra using this tank type required spacers but a lot did. The spacer chosen was the 1962 Fairlane fuel filter assembly distance pieces, three per Cobra if required. Ford Motor Company did not sell the spacers in the service channel so if required you hunt parts salvaged from Fairlanes or you make some replacements from mild steel unfinished bar stock.

Hi it matches the original tank on CSX2367. Dave

More photos of tank
 

Here are a couple more photos.

It’s in pretty nice shape! Looks like there might be a repair done on the brace at the mounting plate? Looks like a small weld but pretty nice shape over all. I’d pressure test it and refinish it if it holds!
Larry

Better yet, post pictures of the project!

Does anyone convert the Lincoln tanks to the Cobra configuration?

Mine is made that way but making the bracket to hold it was not an easy project to get correct. We had an original to copy and for reference.
Cobra Restorers sells a new one though. That's the way to go IMO.
Larry

Thanks for your comments! Here’s some of the story. This 55 Aceca was completely gutted long ago and abandoned, probably in Southern California, and we are installing a fuel injected Ford 302 and a TKO 5-speed. Someone (probably in the early 1970s, we guess from some of the stuff that came with the car) grafted what appears to be an entire genuine leaf spring Cobra rear end, differential, suspension, and brakes (four wheel disks) onto it, so it’s a real “Cobraized” Aceca. Before you ask, there are no numbers or anything on the Cobra parts that could lead to identifying the car the parts are from. We looked very hard and thoroughly, but there is nothing. Our guess is that someone totaled a Cobra in the 60s and the Aceca owner scavenged the usable parts from it for this project, which was never completed. We’ve been working on it for more than a year.

Those original modifiers/builders did a very poor job, so we redid everything they did. For instance, they did not realize (or care?) that the Cobra diff housing was significantly thicker than the Aceca housing, so when they added the Cobra diff it lengthened the wheelbase by more than an inch! We removed the bad graft, moved the diff housing forward to make the wheelbase 90 inches as it was originally, and among other things, strengthened the frame by sleeving the main frame tubes and adding frame braces where necessary to stiffen it up. There were some badly corroded (electrolysis) lower frame tubes and also some broken joints, which we have replaced and repaired.

In addition, the aluminum body was pretty banged up (mostly in the nose) and had lots of bondo in it, which we couldn’t see until the car was soda blasted to remove the paint. Then we had to cut the body to be able to remove it so we could work on it and the frame. The body is about done now after more than 200 hours fabricating and replacing panels, straightening and smoothing, etc. It’s a beautiful job.

Original Acecas were very light cars (less than 2200 lbs), and of course were built to have an inline 6 cylinder motor of no more than 150 hp. I’ve attached a few photos (some from when it was purchased) showing the Cobra parts and some of the frame stiffening. Comments and questions from Cobra folks are more than welcome. I have lots of photos of its past and present state, but can only post 5 at a time here.

Wow, quite a project! Front uprights look like Ace. It's been converted to rack and pinion steering. Lots of work but a very cool project!
Larry

Now is the time to reinforce and prepare for the 289....
Awesome, keep up with pics and progress.

Just a thought but since you are that far apart and since you plan on installing a V8, you may want to sleeve the frame now.

Thanks for your suggestion. I started a separate thread on this Forum ("Aceca/Cobra restomod") that has photos of what we've done to the frame, including completely sleeving both main tubes. I'll be posting more in the future as we slowly rebuild the entire car.,