Xios

Being that this is my first 911or P car for that matter, I'm not quite sure how much road feedback is normal . On some roads I get, what feels like, a slight shimmy on others sometimes more, yet on some roads it feels dead smooth. When its present, It almost feels like a wheel balance issue but it seems to occur across the speed range. Does anyone else experience this? Thanks.

jamesinger

I also just got my first Porsche in Feb. I notice variations in feedback over certain surfaces. For example, I feel a hop on one stretch of freeway that still, even after 8 months, I still think, "is something wrong??" when I drive over it—but then I will see the car in front of me and the road surface reflecting the feel I am getting. Also, there is one stretch of freeway near my house where something must have gone slightly wrong when they put the rain grooves in the concrete because the lines are not straight which causes a "shimmy" or vibration only at certain speeds that is not replicable over other surfaces at the same speed consistently. Where I live in LA has so many different types of bad roads, I guess I just get used to how they feel in each different car but the 911 gives similar feedback to my old EVOs where you feel A LOT and the more you tighten down the suspension towards GT3 or beyond territory, the more you will feel the road feel.

If you feel something is not "normal" what I do is try to replicate it over other surfaces in other areas (i.e. same speed, same driving, different area). What I have found is my C2S is SUPER smooth when it is on a nice surface but the worse the surface is, the more feedback I get, which sometimes feels like something might be wrong. I just try to stay calm when that happens and do the test mentioned before worrying too much.

Bruce In Philly

Just go get a balance and alignment from a good speed shop. They get it and can give you good advice. "Start Fresh" with you new car. Most Porsche owners are clueless posers .... the car can be all out of wack. If you never had one, you don't know what is normal. These cars a very sensitive to alignments so you need a good speed shop.

Peace
Bruce in Philly

larrysb

They should have good road feedback.

Bruce is right on the money though. You should get it to someone who knows how to align cars, and especially knows how to align Porsches.

My own 997.2 has a date with the alignment rack this week. Although I bought it used about 7 months ago with good tires on it, and the alignment seems OK, I had a run in with a puncture right near the sidewall. Ordered a couple of tires from Tirerack and had them put on, only to discover I have a bent rim! No shimmy in the wheel or anything, but one of my fronts has a quite visible bent inner rim. We decided that while the existing alignment wasn't wearing badly, they could do a better job.

Found a set of used, clean, Carrera S II wheels (same as what's on mine) as 3 of the 4 were curb-rashed to heck anyway. So swapping in a new set of no-rash and no-bend wheels and getting a full 4-wheel alignment done.

gtvr6

I'm going to throw my $0.02 in - check your tire pressure and make sure it's not off from side to side (from what I've read, tire pressure should be F32/R38, but I'm running 34 on the fronts - I wouldn't mind hearing peoples opinion on tire pressure without sparking a forum war). If it's slightly off, you can feel a difference.

FZP

I agree with the above. These cars, especially running Michelin tyres are sensitive to pressure. Just being out by 2 psi can make the car feel broken. Start with the cheap stuff and work backwards I'd say.

jamesinger

^^^ this is all good step by step advice above.

1. test a few different conditions to see if it is a consistent/replicable issue.
2. check tire pressures and I would add tq the wheels to spec.
3. if 1&2 above do not eliminate the issue, have the alignment checked and check the wheel balance.

Xios

Thank you for all the responses. I'm thinking that it's road surface imperfections. It seems to occur more on concrete roads. I rarely get it on nice blacktop. I will be more aware of the pressure. I do keep the tpms screen up all the time but I guess I'll pick up a very accurate pressure gauge. Hopefully thats all it is. If not, any recommendations on good indy shops in the NYC area?

gtvr6

I didn't recognize you were in NY - What Part of the city

midnight 911

Xios

Mine came with N1s in the front (don't see the pilot logo) and pilots in the back with10k on the clock. I put 4k on it in a few months. What was OE in 09?

midnight 911

jrp911

I've been having this same issue with a 2010 C2S I purchased back in April. The tire shop I've been using for years said my nearly new Bridgestone tires are cupped, and that's what's causing the issue. Since the tires have tons of tread, I didn't want to replace them before trying a few other less expensive things first (tires balanced, repair on a slightly bent front wheel, alignment), plus I deceased the tire pressures. I think lowering the tire pressures helped a bit, but I still have the problem. Like others have said, it comes and goes, mostly depending on speed and road surface. It's definitely worse on grooved freeway concrete, and pretty much disappears on newly paved freeways.

Hella-Buggin'

OK, hate to ask a stupid question but I've seen this question posted before.

Are your tires matching from side to side and front to rear?
Are your tires aged out (5 years)?
After that, pressures then wheel balance, then alignment.

Xios

So, I think this is could be the issue, my date codes read left front 1908, right front 3709, right rear 3116, left rear 4015. I guess my front tires are original all are sport pilot. Should I change all four? It tracks dead straight,, do I need an alignment?