I would like to build a JDM car but am curious as to what classes these cars might be placed in. Does anyone have an idea?

Skyline R33 GTS  - RWD 2.5L inline 6 - single turbo
Skyline R33 GTR  - 4WD 2.6L inline 6 - twin turbo
180SX/Silvia S13 - RWD 2.0L inline 4 - single turbo

Appreciate any feedback,

N8

2.0L * 1.4 turbo correction factor = 2.8L = GTM
2.5L * 1.4 turbo correction factor = 3.5L = GTM
2.6L * 1.4 turbo correction factor = 3.64L = GTM

They would all go into GTM.  Typical competitor car would be a 911 GT3 Cup or race prepped E92 M3.

No IP1.  Rule 18.2.D: "Production cars will normally be only those cars that are series produced for
North America in quantities of at least 2000 per model sold."

Technically no, see rule 18.2.D above.  If you're stuck on it being a RHD car, you'll have to race it in one of the GT classes.

That said, I don't know if anybody would care if you did bring a RHD RX7 to IP1.  Bit of a gamble to try it, since if anybody did bother to protest your car, it would clearly be illegal for the class and pretty much impossible to fix.

Not too many people show up for IP1, so you might get a bit lonely out there.  Most races last year there weren't any IP1 cars.  A Corvette Z06 showed up for 2 races out of 7, so did a base model Corvette and a BMW 330is.  There was a 300zx that was there for one race too.  That's about it.

Build a 1.6l Miata or CRX and you can race in IP3, which probably is the biggest group out there with a dozen+ cars at every race.  Or an S2000 in IP2.  You'd have another guy with an S2000 to race against, plus the occasional Integra GS-R or Type-R.

I realize the smaller NA cars are not everybody's cup of tea, but if you're on a tight budget and want close competitive racing it's the best option you have.

I suggest renting a bunch of different cars in different classes.  After three years I have settled on a class and had a lot of fun in the process.  Lots of folks in the club have cars to rent from Formula Vees to Hondas and Porsches.  Its the best way to get started and you get to know people along the way....

Ryan

Our Administrator runs a RHD RX7 but he is in the WSC P2 which is a legal class for that car.

I have a RHD 1st Gen RX7 and if I prepped it to the IP rules I'm sure I could run it there without much of a hassle. You'd have to be pretty petty to protest a car based on which side the steering wheel is on as long as the rest of the car was prepped according to the rules.

In my case I put the bigger motor in and upgraded the front brakes so I have to eitehr run in the Westcoast series or run GTM.

Cacc IP rules are as per the Scca IT rules. Cacc rules say that all cars must have been series produced for sale in North America in and a minimum of 2000 units.
The Scca rules say offered for sale in the United States.
I see no minimum numbers here, but they give a list of eligible cars.
Right hand drive cars would not have been series produced for North America.
For Cacc I see this car fitting into the GTs group only.
This means full safety equipment as if the car was prepared for Scca GT classes.

Cacc IT rules:
18 IMPROVED PRODUCTION

18.1 Definition
Improved Production is intended to provide a place for newer models of vehicles to race with minimal preparation other than the installation of standard safety equipment. In addition the cars shall conform to commonly recognized preparation rules to allow
participation in events governed by other sanctioning bodies.

18.2 Rule Compliance
A. All vehicles must comply with the relevant regulations contained within this CACC rulebook, as well as any applicable regulations that may be in the current competition year ASN Sporting Code.
B. Regulations for the preparation of cars competing in this class shall be those published for the current competition year by the Sports Car Club of
America for Improved Touring IT category in the GCR‟s. The regulations shall not include the addendums published in FastTrack during the current competition year.
C. When a conflict exists between the CACC and SCCA rules the CACC requirements shall be considered the requirement.
D. Production cars will normally be only those cars that are series produced for North America in quantities of at least 2000 per model sold.
E. Competitors shall have available at all times, a copy of the manufacturer‟s workshop manual and/or official specifications for the vehicle entered.
F. The onus is at all times upon the competitor to ensure the eligibility of their car. On the other hand a protest against a car, that is for example, based on
the absence of a valve cap or a cigar lighter, will be deemed vexatious.
G. Under unusual circumstances, it may be reasonable to permit a competitor to deviate from an official specification provided such variance would clearly
be of no consequence to either the safety or performance of the affected vehicle. Permission may only be granted by the Chief Steward in consultation with the chief Scrutineer. All variances must be noted in thevehicle logbook and designated „permanent‟ or "temporary‟.

From the 2011 Scca GCR:
9.1.3. IMPROVED TOURING CATEGORY

These specifications are part of the SCCA GCR and all automobiles shall conform with GCR Section 9.

A. PURPOSE
Improved Touring classes are intended to provide the membership with the opportunity to compete in low cost cars with limited modifications, suitable for racing competition. To that end, cars will be models, as
offered for sale in the United States. They will be prepared to manufacturer’s specifications except for modifications permitted by these rules.
Cars from the previous four (4) model years and the current model year will not be eligible. No car older than a 1968 model of any listed vehicle will be accepted for Improved Touring competition. Turbocharged/Supercharged cars are not eligible for Improved Touring competition.

See the response to the question posed just above yours. That may enlighten you a little.