Joel N wrote:
SP has classes for IT-A-B-C-E-R racecars and they are allowed to tune. So in turn SP will allow tuning.
Gotta be careful - the IT classes have to follow the IT rules and *not* the SCCA autocross rules when competing in SP classes. This includes wheel widths, min weights, all that stuff.
But as for ECU tuning:
Quote:
15.1.D - Alternate computer control modules may be used whenever an equivalent change to the conventional system is allowed. For example, alternate computer module control of ignition settings or fuel injection is allowed.
15.9.A - Any ignition setting, adjustment, or system may be used subject to the requirements of Section 15.10.D. This does not prohibit the use of “two-step” rev limiters used when the car is stationary
15.10.C - Carburetors, fuel injection, and intake manifolds are unrestricted subject to Section 15.10.D.
15.10.D - Traction and/or stability control systems, as defined in Section 12.12, must be standard parts at standard settings or electronically disabled
Lots of SP cars are running full standalone setups. All they are restricting ECU wise is aftermarket traction control.
And the turbo cars have special restrictions:
Quote:
15.10.C.4 - Turbochargers and/or superchargers (forced induction) may not be added, changed, or modified (this does not allow ceramic coating of turbochargers). On vehicles originally equipped with forced induction:
a. No hardware changes or alterations to turbocharger(s) or supercharger(s), in size or number, are permitted. Turbochargers or superchargers may be updated/backdated only in conjunction with the accompanying complete engine unit.
b. No changes are allowed to waste gate(s) size, number, or location. No changes are allowed to variable-geometry turbine (VGT) hardware.
c. No changes are allowed to supercharger drive system pulleys. Belt tensioners may be added/changed to reduce belt slip.
d. No changes are permitted to blow-off/pop-off valves.
e. Compressor bypass valves (CBVs) are considered part of the air intake system and may be added, replaced, or updated/backdated independently of the other components of a forced induction system.
f. Boost regulation systems, either electronic or mechanical, and electronic fuel cuts referencing boost pressure may be altered or modified except as prohibited herein. Boost pressure changes resulting from authorized changes are permitted.
You are correct in that SP does not "build" off ST for allowances, but I have yet to find anything in ST that isn't also legal in SP.