STX Rules and Setup Questions

[cjd]

Originally Posted by renfield90

Funny, because I damn near raw timed STR this weekend in competition runs (and definitely did in fun runs). And not counting a diff I still need to spend another 4-6 grand in order to get the car where I want it.

There are so many variables... but I'd have to agree.

My car (not me driving...) raw timed STR yesterday - it wasn't the very best of the best in either class, but the STR winner is definitely very competitive and the driver in my car is on his first year AutoXing... normally CS and 2 times in an STX car (first time in mine) though other racing under his belt that's probably not hurting (that's what I tell myself, anyway...)

Lots of prep in my car but no diff, too much spring, and probably way past their prime tires (~240 runs + ~5000 miles and basically 2 full seasons... and not to the wear bars yet! RE71R) I have no idea what I want to do for suspension, but think I need a change there. What I have starts to really shine as grip goes up, but it's rarely there.

The day kept getting faster every run and my co-driver got the last two runs, but... he out-drove me where it mattered too. I benefited a ton from the experience though. Also, about half the top 20 were ES Miatas, so it was that kind of day. Started off wet and (mostly) dried up as the afternoon wore on, but every run was a tiny bit different than the previous.

[renfield90]

Originally Posted by DocWalt

STX would have beaten STR at nationals in 2015, lol. Sure, probably different rubber down on course, but still...

What would you want to spend 4-6 grand on? I feel like my 75% build was pretty fast and there were a lot of easy changes to make still.

More power: over/front pipe with a high flow cat plus a balls out 100 octane tune, depending on noise might have to replace muffler delete with a small custom muffler (we have a 92dB site)

Less weight: lighter wheels (my current ones are ~19lbs), AP sprint BBK, probably even consider a lightweight battery

Better suspension: looking at pimpy top hats front and rear that will let me run the car lower without going further into the bump stops than I already am, plus all the bushings, and maybe stiffer springs

That's just off the top of my head, without going to the rule book to see what else I could do.

[14stu]

Originally Posted by renfield90

Funny, because I damn near raw timed STR this weekend in competition runs (and definitely did in fun runs). And not counting a diff I still need to spend another 4-6 grand in order to get the car where I want it.

I race in the Texas region, we average nearly 150 cars at our events and both STR and STX are routinely two of the largest classes with 10-15 competitors in each. The top STX cars usually finish around the mid-pack STR cars (still amongst the fast drivers but never faster than the fastest). The top 2-3 STX cars sometimes out pax the top STR cars, but only rarely if they both run in similar conditions.

[renfield90]

Originally Posted by 14stu

I race in the Texas region, we average nearly 150 cars at our events and both STR and STX are routinely two of the largest classes with 10-15 competitors in each. The top STX cars usually finish around the mid-pack STR cars (still amongst the fast drivers but never faster than the fastest). The top 2-3 STX cars sometimes out pax the top STR cars, but only rarely if they both run in similar conditions.

There were 9 STR cars yesterday. I raw timed all except the fastest, and he didn't clear me by enough to beat me on index. We had an event Saturday as well with a similar result.

They are good drivers and well prepared. One of them is driving a jacket winning CSP car de-modded to STR, another one beat up on the Texas STR mafia at the Mineral Wells pro a couple years ago

On the right course though (like last month's) where I run out of gearing but the STR cars don't, I get destroyed...like 9 tenths back on raw time. Days like that I'm very glad we're not in STR, we "only" have Minis to worry about.

[bslate3]

Moving to STX next year. What exhaust yields the best results without being insanely loud?

Also I like the idea of the better midrange with the UEL. But will EL header with better top end be better for large national courses?

[cjd]

Originally Posted by bslate3

Moving to STX next year. What exhaust yields the best results without being insanely loud?

Also I like the idea of the better midrange with the UEL. But will EL header with better top end be better for large national courses?

IMO the best header setup for STX is going to be a tri-y long tube: Nameless or Ace - Ace even has different lengths and you can compare between them, but the midrange is better than UEL regardless. That said, you can be competitive with any upgraded header and an appropriate tune. Other EL headers also have solid midrange gains, but if we're min-maxing... 4-2-1.

For the rest: I can only speak of what I've heard where I paid attention. I have a full JDL 3" setup on a Nameless header: ultra-quiet over-frontpipe and resonated midpipe. It's been described as very quiet on course. It gets a touch annoying at cruising speed with the rear seats down (i.e. to/from events) still, a bit of drone. At idle and low-load it's tame once up to temp.

I've also heard the Nameless header-back setup (I believe the larger muffler cans) and it's reasonable - a bit louder. I know I've heard other setups but I don't remember the specifics - including some full custom.

Going with a 2.5" will be quieter than 3" (I sometimes regret that choice... maybe I'll change it) - and any of the well-rated quiet systems are going to perform. Ace has a system in the works still that has a pretty aggressive sound target, but time will tell how the in-cabin sound ends up.

I'm pretty sure folks have been competitive on setups we might never consider (whether simply early adopters and never bothered to change, or otherwise) - which means that you likely have a bit of wiggle room here; if you're getting 100% out of the rest of the car 100% of the time, picking exactly the right bits will help. Otherwise, close enough...

[xwd]

I had a P&L catted header and a 60mm Tomei catless front pipe. I switched to the ACE header with a JDL 3" UQ catted front pipe. I'm using a 2.5" Perrin resonated catback. The ACE feels a little stronger 3200-4500 than the P&L, but you could probably do fine with either one. Guys at the top are running all different headers, so it doesn't seem to make that much difference. Nameless is probably the most popular, JDL is also popular. ACE came around after most built their cars, so there weren't many people using them.

In both my setups, the car wasn't super loud. The resonated mid pipe is the key to not sounding like crap and being super loud. I had a non-resonated Perrin midpipe at first with the P&L setup and it was terrible.

With any of these setups it's pretty hard to not get some annoying drone on the highway especially with the seats down.

[smg1138]

Originally Posted by xwd

In both my setups, the car wasn't super loud. The resonated mid pipe is the key to not sounding like crap and being super loud. I had a non-resonated Perrin midpipe at first with the P&L setup and it was terrible.

I agree 100%. I originally had the unresonated midpipe and it as too raspy and loud combined with a catless header. The resonated pipe sounds perfect IMO.

[justinco]

Originally Posted by bslate3

Moving to STX next year. What exhaust yields the best results without being insanely loud?

Also I like the idea of the better midrange with the UEL. But will EL header with better top end be better for large national courses?

I don't know if my setup yields the best results, but it was decent gains and did not sound crazy loud. Before/After dyno videos in my sig (Project FRS).

I had the Revworks UEL header, Perrin overpipe, Berk high flow cat, and Toyota TRD exhaust on my FRS.

I'll be putting the same setup on my new BRZ here soon, except I got a custom exhaust off a local friend that is basically the stock resonated mid-pipe with a lightweight muffler.

[Shneegle]

I've got the Nameless header and full 3" exhaust. It's loud! Nearly hitting 100dB at rev limit. I get shit for it at every event I go to. Whether it be from the organizers or the announcer of the heat it gets mentioned.

Nameless Header does very well to get a good amount under the curve in lower rpms with the proper tune.

Ace headers I think are getting better gains from tuning than any other header but I have not met anyone with the header to see if I could tell a difference between mine and Ace's.

Plan for off season is to make the car quieter!

[NJ10]

Does anyone have the stoptech ST-40 BBK? What wheels are you using?

I'm trying to decide between the +45 and +35 offset options for the rpf1, main concern being fitment.

[justint5387]

We run the ST-40 but we don't have Enkeis. Running 17x9 +35 Wedsport TC105N.

[tigermack]

I was told the RPF1's don't fit the Stoptech, never tried.

[jonesy]

I've seen a few people asking about running 265s on our cars...I tried it with not great results. Rubs in the front either on the fender with a 5mm spacer (18x9 +35 effective) or on the inside with a lot of steering angle without the spacer (+40) and in the rear. Not to mention RE-71R is over 1k per set and it adds 7 lbs of unsprung weight per corner. Expensive experiment, but I was curious. Will stick with 245s and focus on improving my driving I guess.