what's the correct spacers for a 997.2 WB?
 

I was thinking 5 mm front and 7 mm rear?
(I am tracking the car and don't want to go overboard)

Thanks

That's what I have. But it really depends on the offset of the wheels. 5/7 was perfect with Champion RG5's. Exactly flush with both fenders. The H&R's are what looks like 2-3mm different on the offset and I'm thinking 5mm on the rears would be better. With stock wheels, I don't know but it seems some are going with 15mm so they must be quiet different.

I have OEM lobsters and I'm running 5 in front and 15 at rear. Rims are flush with fenders. Look great.

i have '11 C4.
front: 7mm
rear: 15mm

looks great and not too aggressive. do a search on my username and term spacers and you'll find a few posts

For exemple : i had aftermarket wheels on my 997S and for using the same on my new 997 4S, i'll need to place 17mm rear spacer. It depends of the offset of the wheel.
Vincent

running spacers and require longer bolts? we manufacture custom lengths over OEM to the specs you need in house!

If you're tracking the car, why would you want spacers? You want the maximum suspension travel and don't want the tires to rub anywhere.

Gooooooood point.
Basically I am looking for a compromise which looks better but doesn't inhibit suspension travel - is that possible? (5mm all around?)

Not sure, but the wider (and lower) you go the better chance of rubbing against the arch at full compression. This is the most risky at the front end under hard braking, or if you exit the track and hit uneven surfaces. One guy on here tore up his wheel arch pretty bad just hitting a pot hole. 5mm may not make much of a difference. Those seeking to make the wheel flush with the arch makes no sense to me.