>Yeah, it's a weasel-featured attempt to end-run the intent of the rules,
and
>it's obviously playing stupid semantic games and I wouldn't
>expect to get it through Impound more than once, but the way I read the
rules it's technically legal.
Geez, we've disagreed on a few things in the past, but I see your point on
this one.
>But even if I DID think it was A Good Thing and do this to my car, it is
NOT a
>way to make "infinite boost"! Even weasels cannot break the laws of
physics.
>Every turbocharger ever made or that will ever be made is fundimentally
limited
>in the amount of air it can flow, and thus how much power can be made - and
OEM
>street-car turbos have low flow limits as a general rule.
Yes, but.
But the flow limits and pressure ratio limits of at least some of the
turbofords is high enough to make a *lot* of power within the other limits
of Street Prepared rules, if there were no rule-based boost limit.
IOW, if I could run unlimited boost (IOW, limited only by the mechanical
limits of the engine and turbo, but not by the rules) the stock T3 in 60
trim is capable of putting out ~26 psi gauge while staying in the 70
compressor efficiency range, which is respectable efficiency. The stock SVO
setting is ~15psi.
Flow @ 5000 rpm @ this PR is ~30#/min and/or ~350cfm, which is the limit of
the 60 trim compressor at 70% adiabatic efficiency. At this point, assuming
the rpm limits of the turbo itself haven't been exceeded (it's the Mitsu
turbos on the TurboCoupes that detonate) I've reached over 325hp,
conservatively, in a 2900# car, and I can legally pare that weight some more
while adding lots of chassis stiffness with no net weight gain. And I'm not
even using gumball tires yet and allowable camber changes they need.
Now, because FI is unlimited in SP, I've dropped in a bigger VAF, TB, and
injectors to cope with all this increased flow and fuel requirement.
Chipping that deals with fuel maps is also allowed in SP (the SVO does not
control boost levels through its computer), including additional enrichment
to fight detonation.
And because I can run any air-to-air intercooler (I guess air-to-water is
allowed now, too, for some reason,what's the deal with *that*?) that's
cooled by atmospheric air, I can suck the additional heat out of my charge
air by running a remote-mounted IC that's roughly twice the width of the TC
IC. Drops in below my radiator. IC efficiency is up because it's no longer
mounted above my exhaust manifold as it was in stock form.
And because I can run any exhaust system at present, that 325+ hp figure is
VERY conservative. Even if I must run to the stock cat, I can still pick up
some flow by switching to a single 3" or so exhaust after the cat. In SP,
I'm only limited by noise levels as to the muffler I run, so I make up for
any cat restrictions there.
Now do you want to play with me? Will it work with the stock turbo? I can
find out, if anyone really cares to know.
BTW, the SVO has a dual position boost switch that is cockpit-controlled.
So in the above example, I can switch to a lower boost if it might be
advantageous. And I'll grant you that it's questionable if an AiResearch T3
will stay together at the 150,000 rpm the turbo shaft is doing at a 2.8PR,
but it's pretty likely -- it's doing 130,000 rpm at a 2.0PR.
For my car it's moot, which was part of my point -- the SVO in SP legal trim
*even under the proposed new rule* can make more power than I can use in
autoxing. But is it *right* to impose an exhaust limitation on turbocars
that aren't imposed on supercharged or n/a cars? No to that.
Richard Nichols
rnichol1@san.rr.com
86 Mustang SVO TII 1C: ESP/FSP/?
72 Pinto Sedan 2.0 3J - Original Owner, Restored
On display at the San Diego Automotive Museum,
June 99 through January 00
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