[apexit53]

Per the December fastrack

STU (RWD N/A & FWD).............................................. .................... 315

Electronic Differential Tuning
14.10.Q
Except for AWD cars in STH, electronic differentials may be re-programmed. This allowance only
applies to changing differential behaviors and does not extend to re-programming any other
components.

I know cam is out there for our cars but they also go into STU and with the allowance of the diff tune... cant lie im looking at a parts list right now.

[Ummpwr]

Can you post a link with more rule details. What's the PAX for Stu?

[Scargoes]

Here is the new PAX for 2021- https://www.solotime.info/pax/

[Msquared]

315s are enticing, and it's nice that the class essentially allows all the bolt-on mods but doesn't encourage all kinds of cutting up and gutting of cars like CAM does. OTOH, the problem is the class also includes that AWD boost buggies and the mid-engine sports cars like the Cayman. The pax index reflects that (STU = .828 vs CAM-C's .818). That said, if you try it a lot of us will be watching!

[DaveC113]

I'm interested to hear why you'd choose to run in STU over CAM-C?

[NLZN21]

In reply to the above, it would technically be more limited prep compared to cam. The discussion of the 315 Rwd allowance was one of the final triggers for me to jump out of stu. It will completely change what cars can be more competitive now as there are a lot of rwd cars that can't mount a 3-series tire without fender modifications.. which aren't allowed in street touring classes (rolling only).

[apexit53]

Originally Posted by Msquared

315s are enticing, and it's nice that the class essentially allows all the bolt-on mods but doesn't encourage all kinds of cutting up and gutting of cars like CAM does. OTOH, the problem is the class also includes that AWD boost buggies and the mid-engine sports cars like the Cayman. The pax index reflects that (STU = .828 vs CAM-C's .818). That said, if you try it a lot of us will be watching!

Yeah the boostie cars will be getting more power for sure. Caymans issue will always be wheel fitment, and talking to Camaro owners that also seems to be an issue with some coilover setups and wheel specs on our cars.

This is also probably the only year to try it as 2022 the supra and m2 cars will probably be moved into the class.

Originally Posted by DaveC113

I'm interested to hear why you'd choose to run in STU over CAM-C?

Simple, its a class with a jacket. Nothing wrong with cam, in fact I have to keep myself from wanting to do cam like things to the car, but STU is a SCCA class with a Jacket.. Yes cam has their own but its not the same.

[apexit53]

Originally Posted by Scargoes

Here is the new PAX for 2021- https://www.solotime.info/pax/

Also PAX isnt a selling point for me. Yes locally its fun if you don't have anyone in a class with you but at nationals its irrelevant.

CamC is the easier class pax wise for sure.

[carguy55]

How would they know if you had a diff tune?

[apexit53]

Originally Posted by carguy55

How would they know if you had a diff tune?

I would know, and I don't race that way.

[Woody6244]

Originally Posted by apexit53

Also PAX isnt a selling point for me. Yes locally its fun if you don't have anyone in a class with you but at nationals its irrelevant.

CamC is the easier class pax wise for sure.

Makes it sound like CAM C PAX is soft. Or is STU too stiff?

[Mountain]

Originally Posted by Woody6244

Makes it sound like CAM C PAX is soft. Or is STU too stiff?

It is. I've never understood it in regards to CAM-C. CAM-T? Sure, I get it. CAM-S has a PAX that I would say makes sense. CAM-C should really be somewhere around 0.830.

[apexit53]

Originally Posted by Mountain

It is. I've never understood it in regards to CAM-C. CAM-T? Sure, I get it. CAM-S has a PAX that I would say makes sense. CAM-C should really be somewhere around 0.830.

so for reference. on a 60 secons course in STU id have to go about .8 faster than my car in BS, but only .2 faster in camC to match a BS pax time. Id say pax wise camC is a bit squishy lol

[AustinTXracer]

Having come from many years of running STU in an STI (typically outrunning CAMS), I don't see the Camaro being competitive unless you can get the weight to 3400 or less and use all of the tire allowance. In that case, CAMC would be easier to do than the much more restrictive STU rules. Tire:weight being most important, but power:weight coming in somewhat closely behind. Big factor being weight. Adding tire width is a good step, but removing weight from the car in an STU legal manner will not be easy. Also, will 315's on 11"+ wheels really fit up front without modifying the fenders?