what, if any, difference will i feel if i replace front tires with 245/35? i am getting a set of sport carrera's and the front rims are 8.5", so i am thinking of stepping up a size unless it will adversely affect handling/ride, or would 245/4O or 245/45 be viable options, i am sure there is a lot to consider...tracking is not something i do very often so i am mostly just on the street...if anybody is wondering or even remembers, i have pretty much left off the isea of putting 991 20" rims on, they just look a llittle too 'big' on the 997, even though it is a quite delicate 20 i and i haven't actually seen these rims on the '7' but all other 20's are just too big, not too much too big, but it is noticeable , anyway, thanks in advance , i hope to hear a bunch about this, so many interesting aspects to these cars...

 

That's my plan right now... I have 8.5" fronts with aggressive offsets and I will replace my 235's with 245's as soon as they wear out. My backs are 305's I will replace those to 315's next year

 

I'm running 245/30/20 front, You didn't mention your rim size, 19 or 20? I'm assuming 19s, but I can speak to 20's. Rears are 325/25/20, Fronts are 8.5, rear are 12's. I've driven on stock rims/tires, I only really noticed a difference when doing a track event, having a little more bite in the front with 19's. Obviously this will gain you a few seconds so if that's what you're after stick with 19's. But I use mine for street/spirited driving, so I don't mind the 20's. As per your question 235/245, I didn't really notice that big of a difference, you'll notice a big difference between 19/20 but not really 235/245.

 

The wider front will help reduce understeer on the track. I wouldn't bother with the switch if mine were a strictly street car.

 

sorry i didn't mention that i was speaking of 19's, but did say i have given up on going to 20's cause of the visual...anyway, the Q is for 19's, there will be a track day now and then, but it is mainly for the street and what small visual gains i may make in filling out the wheel well, i have lowered it with eibach's and 20's really would fill out the wells, a bit too much for my mind so i stay with the 19's, just bought a set of sport carrera's and the fronts have 8.5" width so 245's should be ok and they give a couple mm's greater diameter with being 35% of 245 instead of 235...splitting hairs, i know, but it all ads up...thoughts?thanks

 

You might negate a bit of push with the wider tires in front, but you may give up some road feel and get a stronger case of road-imperfection-tracking. Grooves, offsets, etc. will take the car where they go, rather than where you want to go as the footprint loading per sq inch is reduced. I doubt that one CM is going to matter much in any direction, but the car generally has enough rubber so it's not a tradeoff I'd be anxious to make
V

 

just thinking i will gain 5mm in offset with the 245 over the 235 and then i gain 6mm with the 8.5" rim over the 8, also the ET is 55 instead of 57 do i gain 2mm more there, maybe that is too much of a push towards the fender, might stay with the 235's

 

You're not really going to notice much if any difference. You might get a little less understeer on the track, but probably not. If you're at the limits and pushing the front end already the slightly wider tires and footprint aren't going to change that.

 

I switched to 245.35.19s up front on my last three cars. I didn't have any issues with the increased size.

 

Any improvements?

 

Maybe a bit less push.