snitm

Looks like X-Prepared (aka "Prepared class X") requires a roll bar and harness at a minimum. I didn't intend to go that far just for my first year trying autocross

f20kills was saying he shifts at around 7500 or 7600. Like f20kills I'm tuned to 8200 but I have a shift light configured for 7600.

ViperASR

That feels odd for X-Prepared. I don't have the rulebook in front of me, but I can't imagine an autocross class requiring a roll bar and harness at minimum.
I'm trying to think of X-Prepared cars I've seen nationally, but can't remember if they had harnesses or not. I know locally we use X-Prepared as just a class dump for people with odd mods, or if you're just looking to have fun.

My suggestion, as it seems you have, is to reach out to your local region.

spaded.racer

I think you're reading into it too much.

Solo Prepared Rules
It just mentions driver restraints, which your stock seat belts meet the requirements.

Roll Bar Standards
It doesn't sound like the factory hoops would meet the specifications of the rules but I don't think your local region would boot you due to safety and I doubt anyone would protest.

Mrsideways

Just like a K24 it's really not a 2.4 (Most K24's you see are a .5mm overbore making them 2.4's.) . It's a 2.35. If you look at the jump in displacement it's actually less displacement increase via percentage as going from a F20 to a F22. It's something to the relm of a 7% jump in power.... Or identical 2.2 to identical 2.4 +/- 15hp and 11tq. Gains your going to make over that will be from better cams, higher compression, ability to use a larger intake etc etc. But it's really not a large power bump. The potential larger power bump from displacement would be to sleeve the block and run a 90mm piston and bump it to a over 2500cc. That's a 15% bump and starting to make an engine rebuild sound worth it.

miamirice

I was thinking to sleeve the block anyway. Inline pro mentions open and closed s deck, what's your thoughts on that? I worry about heat/cooling because I think many of these builds are street cars or cars that do 2-3 laps and come in. I want something that can sustain full sessions. When you say longer intakes are you talking ITB's? My plan at this time is to shelve my civic when my car is reliable. Currently it has an electrical hacking that is being sorted out in Sebring. Run the current motor which is weak and either send my spare motor for a build or swap the motors out. My car is currently in Sebring. Is it difficult to have a motor dynoed that's out of the car?

whats your power goals with your K24?

Mrsideways

Larger intake..... with more displacement the engine can be woken up with bigger intake manifold/tube and porting that normally would provide no gains on smaller displacement. I'm not sure a 2355cc engine is a big enough difference to benefit a lot from this stuff since the S2000 head has such large ports to start with but it's worth trying on a F24 and probably a waste of money on a F22.

Mine. To make 207avg on the dyno and reclass to C since no one runs in 3 or 4. The goal is to figure out how to make 300, but dyno 200 right. Still working on that. The AVG I ran with at Sebring was 235whp at 2850lbs. But I'm not sure it was that high, I think my Ethanol percentage was varying and screwing with the hp greatly. I'm in the process of putting a Flex fuel sensor in then back to the dyno. Which might as well be open heart surgery.

f20kills

Few things...2.2 to 2.4 with just crank swap and bump in compression (13:1), I made about 40whp more than my 2.2 same dyno.

Second...I just got my TT license, how come no one runs in TT3 or 4? If Im understanding the rules right, my car fits in TT4 perfect.

Mrsideways

That bump in compression was likely a good portion of your gains, also new fresh motor vs old worn motor?

I don't know, it's going to be different around the country. Usually if someone is fast that class will die cause people quit showing up to get beat. I did that to TTC locally with my Mini years ago. took 2 years for people to start showing in the class again. But just no one has run 4 (by no one I mean 1 or 2 cars) locally.

f20kills

Motor was healthy. In my buds car (Ddess) now boosted lol Only had like 30k miles on it.
TT4 records here in SoCal are non existent...so I assume the class is dead here right now. I could get in TT3 and from the looks of it, still be competitive.

slowd16

TT4 is new for 17 so no records anywhere until that track is at least run with NASA.