spacers cause vibration?

[23109VC]

Originally Posted by Lil bastard

You probably just answered your own question. If your shop didn't have the Hunter machine - they didn't dynamically balance your tires - it may need to be done again.

The LFM feature is nice but not absolutely necessary; the 97XX system has done a very good job of dynamic balancing tires/wheels for a decade without it.

But, it's not just a case of the equipment, it's also a case of the operator.

To illustrate; I had a 4 wheel alignment done on my wife's Jag when we got new tires for it. I was allowed to be in the shop and observe. The tech spun the tires up, one at a time, on the 9700. This has a graphic readout and as I was watching, he turned off the machine while the graphic on the screen showed the 1st tire off. I commented and he said " The machine gives us a range and it's within that range..." I asked him to spin it up again and get it dead-on-balls which he did, and repeated for all 4 tires.

Next, the car went to the alignment rack. He did the setup and then started the machine. Because it's a Jag, I copied the alignment specs from the Workshop Manual and had them with me. The spec was 0.43. Again the tech adjusted it until it was at 0.47 and started tightening up the trailing arm. I pointed out that the spec was 0.43 and again the tech said the computer gives them a range of 0.39-0.49. I replied "that's just for schmucks who don't know what they're doing... but I bet you can get it right on the dot..." So he loosened the trailing arm and continued to adjust it until it sat squarely at 0.43 and set the other side the same way. I complimented him saying I knew he could do it. Anyway, that car can have a cup of coffee in the holder at 60 mph and it doesn't ripple.

These machines have universal software such as ALLDATA and such which do not always mirror the specs from the factory workshop manuals - remember these are commercial enterprises, it's counter productive to get things down to the Nth degree, they are built on the Move 'em in - Move 'em out principal. In most cases, this is fine, but with alignment and balancing, precision matters. So make sure you know what the correct specs are and have the tech prove to you that he's setting the car to those specs - despite what his database may say.

Cheers!

you are likely VERY right about that. WHERE it goes is just as important and wha tmachine they use. you can use the correct machine, but if th tech just figures it's "close enough" and doens't make it exact - you get a "close enough" result...

i'll find a shop that does performance car alignments, or maybe take it to the dealer for this one. i know the local Porsche dealer DOES have the Hunger 9700....and if I make a fuss, i"m sure I can get them to do it "RIGHT"....

[Johnny Danger]

Originally Posted by 23109VC

you are likely VERY right about that. WHERE it goes is just as important and wha tmachine they use. you can use the correct machine, but if th tech just figures it's "close enough" and doens't make it exact - you get a "close enough" result...

i'll find a shop that does performance car alignments, or maybe take it to the dealer for this one. i know the local Porsche dealer DOES have the Hunger 9700....and if I make a fuss, i"m sure I can get them to do it "RIGHT"....

What is the verdict on the front 7 mm spacers ? Are they hubcentric or not ?

[manolo]

I have the 7mm/14mm spacers on my 986S. They are hubcentric. The picture shows the outside of the rear and the inside of the front. Its hard to tell but the inside has a bevel to accomodate the stock hub, then a ring on the outside for the wheel. Other than name, they are very comparable to H&R and not cheap cast aluminum knock offs like a lot of the "billet" parts out there.

[Johnny Danger]

Originally Posted by manolo

I have the 7mm/14mm spacers on my 986S. They are hubcentric. The picture shows the outside of the rear and the inside of the front. Its hard to tell but the inside has a bevel to accomodate the stock hub, then a ring on the outside for the wheel. Other than name, they are very comparable to H&R and not cheap cast aluminum knock offs like a lot of the "billet" parts out there.

What brand are they ?

[manolo]

Same as the OP, Maxspeed.

[Johnny Danger]

Originally Posted by manolo

Same as the OP, Maxspeed.

What does the outside of the 7 mm spacer look like ? Can you post a photo ?

[23109VC]

UPDATE----

I just drove my car for the first time today after getting all the wheels road force balanced. WOW. rides sooooooooooooooooooo smooth. rock solid at 75...85...I didn't go too much faster...but it ddrove GREAT. that was the fix!

thanks to all of you who suggested that!

my spacers are on teh car and they obviously had/have nothign to do with causing vibration... car runs awesome.

[Boxtaboy]

Glad you figured it out. Just so you know, Porsche did issue a TSB indicating that you should not use aftermarket wheel bolts that don't have the floating spherical collars that are on the OEM wheel bolts. That's the 2 piece bolt thingy you are refering to in your previous post. They say those floating collars are specially designed to maintain the proper torque, and that using bolts without them (even when tightened to the proper spec) risks them coming loose later on.

I don't think you will have a problem necessarily, but perhaps a good idea to check he torque on the bolts every once in a while.

This guy bought a set of incorrect sized wheel bolts for his car, and this is what happened:
http://www.youtube.com/watch?v=jv4m41viy4I&feature=youtube_gdata

[23109VC]

that video is FUNNY!! oh that poor guy!! that must have been a BAD day.....

lets just hope that doens' thappen to my box!!!

[Boxtaboy]

It is hilarious....except for the guy I guess. Btw, manolo's picture above shows the longer bolts with those floating spherical collars.