> Hi to all. This post is not intended to flame anyone, just to add my
> knowledge/opinions to some threads that have been floating around in the
> last year or two. Your comments, opinions, corrections, and additions are
> welcomed. Please excuse the length, and <snip> most or all of it on
> responses.
>
>
FACTORY LIGHTWEIGHTS:
> I have never (to my knowledge) actually laid my eyes or hands on a
> so-called factory lightweight, and I cannot personally confirm or deny
> that they exist. I can assure you that 67.5 SRL-311-00012 (which I
> purchased in Nov 1968) was a full street car with full frame/bodywork. I
> can also assure you that 67.5 SRL-311-00095 (Bob Sharp's CP/DP race car,
> 1967-1970) came with full frame/bodywork. When I got it in 1974 from the
> second owner (who got it from Sharp in 1970, and only raced it in DP in
> 1971), it still had factory undercoating on it! Later, I ran it in E/P, as
> well as in SVRA vintage, and it got nicknamed "Instant Race Car ... Just
> Add Water", because of how well we did in the rain (and how poorly in the
> dry?). Anyway, if S/N's SRL-311-00001 to -00010 were real factory
> lightweights, why didn't Sharp get one or more? Sharp was the first (and
> at that time, only, I think) "factory" race team (I believe that BRE
> didn't get into racing roadsters until 1968; at least their cars weren't
> 67.5's, so it had to be very late in 1967 if they did race then.
>
> Bob Sharp told me that Fitz's (the late Jim Fitzgerald's) car had the
> lightweight FIA frame under it (it did), but I don't know if it also had
> lightweight bodywork (from the factory, that is! -- Fitz did some
> "interesting" things with his car) or not. My recollection is that this
> was not a 67.5 model. Dave Manzolini also had a late model race car with
> an FIA frame. I crewed for Dave in the 1970's a few times, and don't
> recall anything unusual about his bodywork (other than LOTS of dents --
> but then, I didn't know about lightweights and such back then). I do seem
> to recall that Dave bought the car from a dealer, and drove it on the
> street and for autocrosses, before running SCCA with it; and I also recall
> that he said that he had to ballast the car to meet the minimum weight,
> but that may have been after he lightened it, or after the minimum weight
> was increased. I later bought a late model race car with an FIA frame, and
> can definitely confirm that it STARTED with stock bodywork (or someone
> stuffed an FIA frame under a stock body).
>
> So, there may have been a bunch of cars with stock or mostly stock
> bodywork, and FIA frames (probably 1968's). And then there may have ALSO
> been some real factory lightweights, with lightweight (thin) bodywork, and
> if so, I don't know if they also had the FIA frame [since that may have
> been a later vintage]. Of course, "lightweight" may also refer to things
> other than actual thinner panels -- perhaps some stiffeners or say the
> jack/spare tire mounts were deleted, as perhaps was undercoating.
>
> Perhaps Jerry Krakauer has more on this whole business regarding Fitz's
> car and lightweights, as he was around these folks (Sharp and Fitz) at
> that time, or could get some information on them from Bob Sharp.
>
>
MORE ON ROADSTER FRAMES:
On regular Roadster frames, the main rails are basically built with an
upside down "hat-section", with an additional flat plate welded across the
top (what would have been the "brim" of the upside down hat). Then there is
a thicker "U" section added to the bottom, from the main front cross member
to the forward-rear-spring-mount. Except at its ends, this extra "U"
section is some distance below the bottom of the original box formed by the
hat and plate. Also, late model frames ('68 -'70) have a second set of "U"
shaped braces about 18" long where the main rails "drop down" from the
engine compartment to run under the cockpit floor, and they also have four
horizontal holes through each of the main rail boxes at the very front. I
believe this second set of "U" braces are to prevent frame buckling at the
cockpit, and the holes are an attempt to encourage buckling at the front of
the frame (i.e., "crush space").
Late model FIA frames do not have either kind of these additional "U"
sections, but do have the crush holes. There may also be some additional
lightening (the stock frame has an ENORMOUS amount of doublers/stiffeners is
the area where the main front crossmember is spliced in), as well as extra
stiffeners inside and on the front of the main front crossmember.
Regular 67.5 frames don't have the second set of "U" shaped braces and don't
have the crush holes. They do have "X" crossmembers that are different (and
probably stronger) than the late model ones*. And finally, late model frames
changed slightly in mid-'69 when the roller ball steering box was
introduced. The mount for the roller ball steering box is slightly smaller
than its predecessor, because the new box is "fatter". And BTW, the mount
for the idler box is also smaller (so that they could use the same frame for
either right or left hand drive), and therefore, the idler box requires a
spacer to get it back to the correct position. Therefore, you shouldn't just
put a roller ball box on an earlier frame, unless you want screwy steering
geometry (the right way to do this is to torch the steering box mount off a
late-late frame, and weld it onto the earlier frame in the correct
position). You could put the worm type box on a late-late frame, by using an
idler box shim (but why would you want to?). I'm sorry, but I have no real
experience on frames earlier than 67.5, but I think that early 1600 frames
are just like the 67.5 frames, except that the tranny mount bolts to it
differently (into the front of the X-member, rather than underneath it), and
they have no traction bar mount. And I think (from a frame drawing in a 1500
manual) that the 1500 frames were the same as the early 1600 frames, except
that the very forward crosspiece was bigger. Incidentally, the only place I
have ever found any frame dimensions is in the 1500 manual.
Approximate frame weights: 67.5 = 200 pounds, 68-70 = 210 pounds, 68 FIA =
160 pounds
*up through 67.5, the X-member was formed by one long, slightly kinked box
from left front to right rear, and then two shorter boxes finishing the X,
and the holes for the exhaust pipe were reinforced by welded in tubes. Late
model frames were made with two very-shallow-C-shaped boxes, back to back,
and the exhaust pipe holes are not reinforced.
> Dick Tillinger
> 2334 Hidden Willow Lane
> Allegany, New York 14706
> 716-372-0475 evenings/weekends
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