Can anyone explain the differences between (SM) Street Modified and (BP) "B" Street Prepared?

This is very confusion to me

Thanks in advance

 

Per SCCA 2009 Solo:

Street Prepared – The original SCCA® “street” category, Street Prepared allows
any carburetor/fuel injection system and any ignition system. Turbo/supercharger
hardware has to remain standard, but aftermarket boost control
systems/programs and intercoolers are allowed. Exhaust manifolds and systems
are free. Emission controls are not required for competition, but no internal
engine or transmission modifications are allowed beyond factory specs (no cams,
hi-comp pistons, ported heads, etc). Some cars are able to update/backdate
components like engines, brakes, etc (See Solo Rules for details and specifics).
There are no limits on wheels sizes or DOT tires; racing springs and shocks are
the norm.

Street Modified – The top of the “street” categories, Street Modified allows
anything from Stock, Street Touring, and Street Prepared and just about any
engine and drivetrain configuration as long as the engine manufacturer matches
the body manufacturer (see Solo Rules for details). Four-seaters (BMW, Corolla,
Civic, Integra, Neon, Supra, Talon, VW, etc.) run in SM and two-seat sports cars
(Corvette, CRX, M Roadster, Miata, RX-7, MR2, etc.) compete in SSM. Carbonfiber
hoods, cams, turbo/supercharger kits, etc are welcome, too.

There you have it for SM & BSP class categories

 

For more details:

2009 SCCA Solo Rulebook online (PDF format)

 

Thank you all for the insights.

 

Make sure you familiarize yourself with the wheel/tire regulations for those classes as well. It's the deep pockets for high end race compounds that make the competition in those categories.

 

I hear you, I am running the Hoosier A6's. Are those the right ones to be using?

 

For BSP. I'm not sure what's legal in SM, but the A6 is "the" tire for autocross.

 

SM is any DOT tire and any wheel size. unless its changed.

i was away for a year so i dont remember all the rules as well as i used to. but im sure wheel/tire rules are the same in BSP as well. i know in bsp interior and exterior must remain stock. but in SM its a lot more flexible.

 

BSP allows any wheels and DOT tires as well.

 

I just raced my first SCCA AutoX this past weekend and ran in SM. I had three people tell me I should be in BSP and three tell me I was right in SM... I think the big question is my 4" IC. From what I read above, the aftermarket IC is just fine in BSP (where I am guessing an Evo is far more competitive than in SM?). My mods are all listed in my sig. Let me know where you guys think I should register. I want to be honest with my classification as the SCCA tech guys dont look like they will catch me if I am out of class...

 

I think the GSC S1 cams put me in SM......

 

15.10.C.3
As utilized only on engines originally equipped with forced induction, induction charge heat exchangers (known as “intercoolers” or “charge air coolers (CACs)”) are unrestricted in size and configuration. Air-to-air CACs and radiators for airto-liquid CACs must be cooled only by the atmosphere, except for standard parts. Body panels, fascias, or structural members may not be cut or altered to facilitate CAC installation.

The intercooler itself is legal, but if you had to cut or change anything to make it fit, that bumps you to SM.

 

15.10.AA.
Camshafts and related parts must remain standard...

Cams=SM

 

SCCA Solo Tech is mostly just a safety inspection. The SCCA officials aren't in charge of enforcing classing, your competitors are. You don't get bumped out because you are illegal. Somebody must protest you, then you are bumped.

d

 

Alright, thanks boost for the clarification. I explicitly got an ETS wide tank IC so I didnt have to modify anything. I will try to run BSP next time.

EDIT: I did look at the SCCA Street Prepared rules and did confirm what boost said, if you have a stock IC, any aftermarket piece that fits is allowed.