"You want a smaller converter for more stall," says John. "It has become
very hard to get ahold of the old Opel cores, and the advent of larger
engines in the sport justified a change to a slightly larger converter.
The Opel was 8.75 inches, and the core that we selected to supercede
it as the J.W. Super 8 is just above nine inches in diameter. I think
that, due to the size of today's motors, we have lost nothing in regards
to performance, despite the larger diameter."
SPLASH! One of J.W.'s technicians watches
as a stock converter is cut in half and residual fluid sprays from
it. Once apart, the pieces will be carefully examined and modified
as needed before going off to be furnace-brazed.
This close-up shows the furnace-brazed
pump. As noted, each fin is now securely welded in place. Conversely,
the stock version simply has the unwelded fins bent over in this
area. For performance purposes, the fin angles are also hand-adjusted
to suit the specific use of each J.W. converter.
Rebuilding a converter begins by cutting the
core open and closely checking the internals. J.W. then sends the components
to be reused out for furnace-brazing. This process insures that all components
are properly and permanently attached to one another. Furnace-brazing
also serves as a mild heat-treating process on the metal itself.
"Exploded" view of a converter shows the
various parts, prior to final assembly. On the far left is the
turbine, which is one half; the section above that is the pump.
In the center is the stator-sprag assembly, which will fit between
the two pieces. The assembly is then mounted to the cover on the
right. Finally, the proper neck or "snout" (shown at lower right)
for the specific application will be welded to the converter.
Here's an example of J.W.'s aftermarket
stator assembly which already has a "low-drag" roller sprag
mounted inside. The anti-ballooning plate (the piece with the
raised disk) can be seen in the center of the cover in the background.
In rebuilding, J.W. makes use of newer parts to supplement what is
left of the core. Some of these parts come from other sources in the
aftermarket, such as the Borg-Warner sprag (or the super-duty, low-drag
roller sprag that often replaces it). J.W. uses its own anti-ballooning
plates, as well as a heat-treated, heavy-duty stator (the vaned piece
that supports the sprag, critical to the converter's operation) that
is manufactured for J.W. from the equivalent of T6-grade aluminum alloy.
These parts have been developed with input from personal friends of
John who have a great deal of knowledge about the industry.
page
2 of 3
Copyright 1999-2001, Drag Racing Online
and Racing Net Source
