Javelin said:
In reply to CyberEric :
If I'm reading the Solo rules correctly, Street now has unlimited tire size as long as it's 200TW and fits on the stock rim width, and is +/- 1" in rim diameter. I can go 16"-19" on the SS/SC and even run different front/rear configurations. Hmmm.
My Focus ST is my 4nd Street class car and 5th car specifically bought for AutoX. I've spent a lot of time reading the rules and asking the right people questions.
You're reading the rules mostly correct.
if you want to run the LSD... you'll be working with whatever wheel size came on that option package. or if multiple options were available, you have to choose 1. so if 17's or 18's was available, you have to run wheel sizes +/- 1 inch of 1 diameter. you can't chose both..
also, if the option package with the LSD involved any other parts, spoiler/seats, etc. You have you install the full package to be legal.
now back to the numbers, as Gumby Said the Focus wears 18x8's and almost everyone runs 17x8's nationally so you're at a large disadvantage there.
I'm running 245's for nationals, but a lot of the class does run 255's.
MINIzguy said:
You can get around -2° camber once you grind the strut, factory alignment procedure too. Can't do camber bolts. You should probably do 225/45/17 all around, which is the same size as the FRS/BRZ so tires should be cheaper. Throw on a rear sway bar, everybody talks about the Powell bar, and some decent shocks and it should be fun.
Now it sounds like Chevy did give you one advantage if there is indeed a TSB allowing for the enlargement of strut holes to get negative Camber. You would need to be able to prove this for national competition.
Now the Focus has been running the class the past few years, but the GTi with the updates a few years ago has become a popular alternative, although with a only 7.5 inch wheel.
This year the 2018 Civic Si has become the new hot contender. almost all the people who bought G street cars in the past 12 months bought Civic Si's. WIth about a degree of negative camber and a real diff people seem to really like it.
The Curb weights are also a bit misleading... We've got a SCCA G Street Solo Group on Facebook and people have been openly sharing weights and the ST built to the rules(spare tire removed, which is 50 lbs by itself, exhaust with no muffler and thinner tubing from the catalytic converter back and downsized wheels and a 1/4 tank of gas) race weight is down at 3050 lbs. the Civics are around 2800 flat and the GTi's are 3100+.
So the civic's have basically all your weight advantage, have a real diff and get camber, but have a full inch more tire than you with their 17x8 rims.
Now, i'm not saying don't build the car, but definitely understand that you're going down a path that's not what is considered to be a recipe for success at the national level.
I'm the first to say it's better to be at your local autox in an uncompetitive car, than at home not driving. But I definitely want you to be evaluating this build with eyes wide open.
Now, While the 200TW tire's don't "like" pinch as the Hoosiers did as Ian F says, they still work very well while pinched and it's the popular opinion of most people is to pinch tires at a national level. Pretty much all of G street pinches 255/40R17 on a 17x8 if they can afford to.
E street is Pinching 225/45R15's on 15x6's of the 99/2000 miatas or the 15x6 15x7 stagger of the MR2 Spyders.
EDIT: added quoting because I was making MiniZ crazy with my replies only.