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Re: Engine Rebuild

To: spitfires@autox.team.net
Subject: Re: Engine Rebuild
From: Terry Thompson <epharisto@yahoo.com>
Date: Thu, 30 Nov 2000 06:43:22 -0800 (PST)
I don't know about 10,000 hp out of a single over head
cam four cylinder with about 100 cubic inches of
displacement, but I'd have to agree with every other
comment Nolan made.

There's so many options and combinations of parts now
for spitfire blocks, it's difficult to say what is the
best set-up. I've been beating my head against a wall
trying to decide.

Most people choose to work with what they have and
what is proven by using the Triumph Competition Prep
Manuals. You'd use existing blocks, heads and cranks
that are machined for balance, weight reduction and
flow. And upgrade to over-sized pistons (TR6), sport
cam, and higher flow carbs.

But if you want to spend some deneiro, there are
forged and aluminum pistons ($500), chrome-moly
connecting rods ($700), billet cranks ($3k), titanium
valves ($400), quad carb setups ($1k) or electronic
ignition systems ($2k), superchargers ($2k) and
six-hundred dollar roller-rockers that will work on a
spitfire engine. And you can spend some good money on
ceramic coatings (especially if you start coating
everything including timing chains and roller rockers
etc.)

First: try and set a limit to what you are willing to
spend. Then look at all of the options that are out
there, and decide which ones will fit within your
budget. (make sure you figure in some buffer for
incidentals like hardware gaskets etc.)

Then take the list of items that you think will work,
and ask someone like Mike Lewis of Protius or Ted
Schumacher of TSI if it's a good plan to put those
pieces together. Some things are sort of common
sense...like buying a $2000 super charger and using it
on a ZS carb and stock cam...probably not the best use
of your $2000.

You can easily surpass $10,000.00 on parts and
services alone if you add it all up.

In the least you should have the block and head
hot-tanked and magnafluxed. And consider shotpeening
on cylinder walls. Machining the engine as described
in the competition prep manual is not the cheapest
thing but does improve upon an already proven engine
design.

Companies like PAECO will sell you a stage 1,2,3,4
engine but the stage 1's (pretty stock except for a
hotter road cam and head porting as well as balancing)
start around $3,000. The stage 2s are around $5,000
and the 3's and 4's they don't list because it depends
on what performance components you choose. The above
prices also required your old engine as a trade in.

Now for other problems. Let's say you've gone ahead
and spent $10,000 on your engine and it's built
producing close to 200 horses. I'd like to start a $1
pool and see who can guess how long it will take
before you tear the differential or transmission out
of your car when you excellerate too fast.

The triumph components are well made, but even the
works spitfires with their estimated 100 hp, had
modified TR4 tranny components for more beefiness. In
the least, such an engine will probably go through
U-joints at an alarming rate and torsion on other
components like your drive-shaft and half axles will
take it's toll. Not to mention that such an engine
requires lots of care and upkeep beyond that of a
stock TR. Constant adjustments to roller rockers and
valves are gaurenteed.

I'm not trying to discourage you. Just that there's a
whole lot to think about, and no one out there has yet
been able to say "this is the best combination". I'm
still (after 4 months) mulling over my twenty thousand
dollar list of options to decide which items I'm
willing to take a chance on and which I'm going to
red-line to bring the whole concept into budget.

I'm actually shooting for a HP range but it's
difficult to tell what sort of affect/effect (?) these
parts will have to boost hp. If it's marginal (Eh,
you'll get another 5 horses out of that $3,000.00
part) then off list it goes. Especially since everyone
you talk to has a different opinion about what is good
hp value for the dollar.

But then the greatest fear is spending several
thousands of dollars on engine components, then
getting it bench dyno-tested and instead of your 57
bhp, you get a 59 hp. Or what is probably even worse
and more likely, you over-shoot your optimal HP goal
and your having to crawl everywhere so you don't tear
out your drive-train. Then there's always the
possibility that someone didn't torque something right
and you throw a $250 forged piston head through your
$2000 ported, polished, titanium valved, ceramic
coated head (and your recently painted bonnet to
boot).

-Terry
"Oh...Those are speed holes. They make the car go
faster" - Homer Simpson

--- Nolan Penney <npenney@erols.com> wrote:
> 
> There's an old saying "speed costs money, how fast
> can you afford to
> go?"  It's as valid today, with you, as it was then.
>  If you've got the
> money, you can get 10,000 horsepower out of that
> engine.  Gonna cost you
> upwards of half to a full million dollars, but it
> can be done.  I say
> that to point out the folly of your question.  You
> need to put some
> parameters in it.  What kind of money do you want to
> spend?  What kind
> of performance do you want?  What about life
> expectency?  These things
> all sway the modifications.  After all, nitros and
> 40psi of boost are
> great power increasers, but life expectency is
> rather short.
> 
> As far as every trick in the book, pick up every
> engine book ever
> written, and study them.  Then, you will no most of
> the tricks in the
> book for squeezing power out of your engine.  And as
> soon as you've done
> that, know you're out of date immediately, because
> in the time it took
> you to read these words, at least 60 new tricks have
> been discovered or
> improved on.
> 
> As an immediate suggestion, dump the dual exhaust,
> that's costing you
> power.  Then do some serious tuning (how did you
> select the needles?
> what is your advance curve? etc)


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