Kreafles Cross Ram

12/22/05

Subject: Greg Kreafles Chevrolet Production “Blip” Cross Ram

Part Number: Manifold Upper Half – PN# 3941130, Date code – 9-26-68

Manifold Lower Half – PN# 3941128, Date code – 1-20-69

Carburetors PN# 3957859, Date code – 941 - List 4295

GENERAL DESCRIPTION:

· Chevrolet Production Cross Ram Manifold assembly consisting of lower and upper manifold halves, carburetors, linkage, fuel distribution hardware, and open element air cleaner. All components are original Chevrolet built or distributed except for the air cleaner, which is aftermarket. In general, all components present in excellent condition (anomalies and production flaws are noted in following text)

	Complete Cross Ram system with Matching Carburetors is in pristine condition having been run for approximately one-half race season. Note: Aftermarket elbow for water return is non-Chevrolet issue
	As above - Now with air Cleaner removed, the excellent overall condition of the components can now be appreciated.

Top Plate

A most interesting and distinctive anomaly appears on the top portion of the manifold lid as follows:

The Casting Date that normally appears on the underside of the top plate was cast into the outer, top surface, directly under the casting part number. To date, only three top plates, all of which were cast on the same day (9-26-68), are known to exist with this anomaly.

Unique to Cross Ram top plates produced on 9-26-68 is the placement of the casting date on the outside portion of lid directly below the Part Number.

Top plate development and progression - General

The earliest production manifold top plates (those appearing with PN# 3941130) did not have casting dates (see photos below). They are most often found paired with O-Dash numbered (Prototype) lower manifold halves produced after 12/15/67 and were among the units pushed to “insiders” through Engineering.


Shown above is the underside of a Top Plate that was part of the first production group produced with PN# 3941130 on the top. Note the absence of a casting date on the underside. The first batch of production Top Plates had no casting dates on the top or bottom. They were produced prior to 9/26/68.	Shown above is a production Cross Ram top plate (cast PN# 3941130 on top) showing the normal position of the cast date on the underside behind the forward carburetor. The above is dated 9-30-68.

The omission of dates on these early pieces was an oversight that was corrected on or about 10/26/68 (the date the subject top plate was produced). The correction (the addition of a cast date) was made in order to be compliant with the standard quality assurance process that tracks defect occurrences of runs based on production dates.

There where two molds used to produce the Cross Ram. One for the top plate and one for the lower half and only one component part from each could be made at a time.

Overview and Progression

The standard procedure was to run a pilot piece or a small batch prior to release. Then evaluate for form, fit and function and either continue the run and/or adjust accordingly.

At the point the date omission was to be corrected, the operator placed the date impression on the outer portion of the top plate in the same position the date appeared on the prototype originally. Regardless whether it was accidental or intentional, the date location was changed after inspection to the underside of the manifold where it was is not outwardly visible once the manifold was assembled. The date position for the upper half was then consistent with the location of the date on the lower half.


Kreafle’s Top Plate above showing the atypical Casting Date 9.26.68 (See Insert) located in under the Winters “Snowflake” and Chevrolet Part Number	Regular Production Top plate illustrates the typical appearance of the production manifold top having only the Winters “Snowflake” and the Chevrolet Part Number

Under side of Kreafle’s production Top Plate illustrating the absence of a Casting Date in this location	Production Top Plate above illustrates the Casting Date 9.30.68 (See Insert) in the typical position on the underside.

Inspected and Package

Often times when a defect or anomaly (in this case a casting date on the outside) does not affect form, fit or function, it is passed and packaged. This practice is especially true for the low volume production parts where there is a high demand, as was the case with the Cross Ram components at that time.

The number 7 inspection stamp (see image below) seen on the Manifold top plate above part number indicates that the piece was pulled, inspected and conditionally approved for packaging. This type of inspection was typical with pilot parts, and random samples based on quality control standards calculated from risk analysis. The stamp location implies that this area was under scrutiny.

To date, the tops found with the 9-26-68 dating anomaly have only been found associated with lower manifold halves dated on 1-20-69 and 1-21-69. These tops have come to be known as “Blip” plates.

Lower Manifold Half

There are a several distinguishing features associated with the Kreafle Manifold Lower half as follows:

The Lower manifold half is dated 1-20-69 and as with most others cast on that date it appears with the “Circle IMP” Inspection stamp (G W with a IMP inside a circle between the letters).

It appears that a casting imperfection exists on the right front intake runner divider where a piece of casting may have been knocked loose during the core removal process.


Top plate removed – Note the distribution fixes were cast into the bottom consistent with the production manifold.	Underside of the lower manifold showing a casting date of 1-20-69 (see insert).

Note Production Part # 3941128, heater hose outlet, temp sender boss and Winters snowflake, typical of the production units. Also note the arrow points to the unusual “Circle IMP” stamp above the production number (see insert).	Arrow shows area where intake divider appears to have been damaged during sand casting breakout phase of production.

Carburetors

The carburetors accompanying the subject cross ram are of the last design which have dual feed, dual pump, center float, full metering bodies with progressive secondary throttle opening. They were released under PN# 3957859, and are identified as Holley List # 4295.

· The production build date (941) stamped on the subject carburetor(s) indicates that they were produced during the first week of April, 1969 and are part the largest batch of List # 4295 carburetors produced.

· All carburetor related hardware including: “Y” block, fuel lines, transfer rod, Heim-Ends, spacers, special screws and nuts, throttle cable bracket and clamp are original GM. The fuel line that connects the fuel pump to the “Y” block has been cut.


Subject Carburetors are match dated and all fuel plumbing and throttle hardware is original GM. Note: Fuel line to Fuel Pump has been cut.	Carburetor PN# 3957859 is clearly shown with Holley List # 4295. The 941 is the date code which translates to the first week of April, 1969

Photo above shows the beautiful original carburetor color and inked inspection stamp.	Perfect example of correct original finishes and colorizations. Fuel “Y” block shows original manufacturers broach marks and typical edge wearing of thin matte finish nickel plating.

Historical Significance:

This research attempt concludes with the successful and comprehensive documentation of a significant race bred Chevrolet development. A works in-progress touched by the greatest engineering talents in the world. An effort that changed the course of racing history and facilitated the most successful automotive marketing strategy for Chevrolet to date by helping capture the prestigious SCCA Trans-Am Series Manufacturers Cup for two consecutive years.

In particular, the subject manifolds top plate represents the cut-off between the first batch of production top plates having no casting dates, and those subsequently corrected with casting dates on the underside of the plates. Furthermore, it is consistent with the pilot batch evaluated prior to the corrected run.

To date, only three tops having the 9-26-68 date anomaly have been found. The date anomaly adds to the character, speaks to the production process and in large part is historically significant in that it lends to the history of the development of the Chevrolet Cross Ram Manifold.

The lower half of the manifold appears with the “Circle IMP” inspection stamp that has been found on parts dated between 1-20-69 and 1-21-69.