Hello Triumphant Types;
>On Mon, 28 Aug 1995, Ross Vincente -- TransAmer. Financial - Los Angeles
>wrote:
>
>> Also, the Mk. I has a Mk. II exhaust manifold on it. Is it
>> possible that since the chassis no. is one of the last Mk. I
>> models the factory simply began sticking on the Mk. II manifolds?
>> Or is it more likely that the previous owner swapped the Mk. II
>> for the original Mk. I manifold?
>
To which Andy Mace replies:
>Either is a possibility; my references aren't too clear on when the
>change was made. However, the point may be moot because...
>
>> And last, the no. on the engine
>> block, GD33718HE, doesn't seem to match up with ANY nos. I've seen
>> [snip]
>
>...that's because what you have is a Triumph Herald 1200 motor, probably
>circa 1964-65
----snip-----
> I suspect that internally the
>engine is almost identical as well, with the possible exception of things
>like valve springs, cam profile, and/or composition of big-end and main
>bearings.
>
Bob adds:
I bought the "Triumph Spitfire & GT6 (a Guide To Originality)" by John
Thomason this week, and have been busy reading this very interesting
book.
Mr Thomason says that the Spitfire 4 engine achieved > 60% increase
in power over the Herald 1147cc engine by:
- twin HS2 SU carbs
- increase in CR from 8:1 to 9:1
- a change in camshaft to one that had first been used on the Herald 948
to increase valve lift from .281" to .312" (valve timing changed also)
- larger valves & changed exhaust valve material to cope with increased HP.
He also goes on to detail some other engine changes which occured later,
during production of the Mk1 engine (con-rods, pistons etc).
Andy Mace continues:
>Yes, it would be worth it to round up an original era Spitfire 4 block
>(FC41xxxHE) and an original cast-iron manifold, but ONLY if you're really
>into the 400 point concours stuff. If not, I'd say let it go.
The book mentions that in Feb '64 Standard Triumph offered 3 different
tuning kits for the Spit 4. The stage II kit was the most popular.
For 179 Pounds Sterling you got:
- an 8 port cyl head
- dual 40 DCOE Webers
- a new inlet manifold
- a four branch exhaust manifold connected to dual silencers.
- a reprofiled high-lift cam
All these goodies upped the HP to 90bhp. A picture of an engine
thus equipped is shown. The tubular exhaust manifold looks very much
like that of a MkII Spit (2 into 2) although never combining into just 1
pipe.
A little more about the book itself:
I was doubtful that there could be much _new_ to say in yet another book
about Triumph Spitfires & GT6's. I've got about every book & magazine
compilation that you can get. I was wrong. This book has *lots* of new
(to me) information. It is immediately obvious that extensive research has
been
undertaken. No minute detail has been spared & an excellent job has been
done tracing the evolution of these cars. This must have been a formidable
task given the (lack of) documentation and production practices of the time.
A "must have" for anyone contemplating a concours restoration, or who has
an unlimited capacity for Spit trivia like me. Unfortunately the book is
almost
exclusively about "home market" cars. The differences in the early US Spits
(vs. UK models) though is minimal. There are lots of good (new) photos, all
the specs,
comm #'s and a list of available accessories and special orders for each
model.
I read the first three chapters in one sitting. The book is available from
the TSSC
(disclosure: I'm a member) or it can ordered from the usual US vendors
(Classic Motor books) etc. of which I'm not affiliated....blah, blah....
Bob Sykes
75, 78, 78 Spitfires
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