Car Shaking!

[Ibn_danil]

I lowered my car the other week and now im having this problem where the car shakes when i open full throttle. I have read many people have had this problem on s2ki, but it didnt answer my question on whats cause it and what do i need to do to repair it.

Thanks- Adam

[ajay]

Pre-empting repiv here... You might want to add a lot more detail. How much you lowered it, what parts you used to lower it. what wheels/tires you have, did you get an alignment done when you lowered it etc. - as much info as you can provide will help remove speculation. I hope you find the help that you need.

[Zeeb]

yea u prolly need an alignment, thats a must after doing suspension work

[repiv]

If you've changed nothing else like rims/tires, then do the alignment. Lowering a car is enough of a change that the alignment is off just enough to cause problems. If, after the alignment has been confirmed and the shakes persist, it may be possible that lowering the car has now altered the internal pressure points inside the inner CV joints on the 1/2 shafts from where they used to mate up (before lowering). Shaking on acceleration on this car is generally a sign that the inner CV joints are the problem and is usually an indication of badly worn or pitted CVs. Lowering can aggravate and/or simulate such a condition. First suggestion (after the alignment) is to install 1/2 shaft spacers. Get the ones that come in halves so the installation is simpler. If this doesn't cure the shakes, then you'll have to do the inner CV joint swap. "Jasonoff" has a write up on how to do this. The other option is to get new or rebuilt inner CVs.

Do let us know how you've resolved this. 1/2 shaft spacers seem to be quite a controversial topic on that "other" forum, but I, for one, think they may serve a purpose.

PS. A friend local to me lowered his higher mileage S2000 and immediately had an alignment done AND installed 1/2 shaft spacers. He has never had the shakes.

[Ibn_danil]

Its lowered on tein springs for now and has the stock wheels with 245 40 in the back and 225 50 in the fronts. But im getting some powder coated s2000 wheels sometime this week so ill go and do everything all at once. But where can i buy the 1/2 spacer from?

[repiv]

But where can i buy the 1/2 spacer from?

http://www.aj-racing.com/catalog/product.php?productid=1396&cat=0&page=2

Or the 1 piece ones but they're harder to install: http://www.aj-racing.com/catalog/product.php?productid=502&cat=0&page=1

[Ibn_danil]

http://www.aj-racing.com/catalog/product.php?productid=1396&cat=0&page=2

Or the 1 piece ones but they're harder to install: http://www.aj-racing.com/catalog/product.php?productid=502&cat=0&page=1

Would the car any different with http://www.aj-racing.com/catalog/product.php?productid=1508&cat=0&page=2 (the race one) or http://www.aj-racing.com/catalog/product.php?productid=1396&cat=0&page=2 (the street one. I occasionally take the car out on some turns and go auto-X.

[repiv]

Would the car any different with http://www.aj-racing.com/catalog/product.php?productid=1508&cat=0&page=2 (the race one) or http://www.aj-racing.com/catalog/product.php?productid=1396&cat=0&page=2 (the street one. I occasionally take the car out on some turns and go auto-X.

You'll have to contact AJ to find out what the difference is. They don't look any different to me.

[Ibn_danil]

Just contacted them they said that the racing one handle more heat and stress. I ordered it today and ill let you guys know when i get it in if i still have the same probleml.. Thanks a lot repiv

[CD7SiRAccord]

I'm not positive, but I believe the difference is that if you are returning the car to stock ride height the street version will allow you to keep them in while the race version you would have to take out. Because not all halfshaft spacers are the same. I have Motorklasse spacers in mine which are 7.5mm and I think T1R replicates some J's racing products in which the J's racing halfshaft spacers are, I believe 10mm and you must remove those before returning the car to stock as well.

edit: Posted while I was typing this. glad to definitely see some clarification :thumpup:

[repiv]

Just contacted them they said that the racing one handle more heat and stress. I ordered it today and ill let you guys know when i get it in if i still have the same probleml.. Thanks a lot repiv

Can't wait. This is a controversy that needs to be set to rest. Do these spacers actually do anything?
I'm going to link this thread by "Jasonoff" and borrow one of his pictures:
http://forums.s2kca.com/showthread.php?t=21680&highlight=CV+joint

See that worn, pitted area in this pic?
http://jasonoff.iroque.com/s2kca/CVSwap/CVSwap16.jpg

This is caused by the corresponding "roller" through normal wear and tear. When you lower your car, the lengths of the 1/2 shafts change and the roller makes contact at a slightly different spot on that pitted area. If it's on the shoulder of the pitted spot, then you can get the "shakes" you feel. By installing the spacers, you move the rollers away from the sensitive part of the pitted spot.
The controversy comes when people who put spacers on cars where the pits have not yet formed and then they say they don't do anything. Well, if the shakes never come, then maybe it did do something. Some say they lowered their cars and never got the shakes. Again, maybe their CVs weren't worn down enough to make a difference after lowering. In those cases, spacers did nothing. So far, no one getting the shakes after lowering has then put on spacers and reported back. You may be the first.
We know that for those who develop the shakes from normal wear and tear, this can eliminate the problem by doing the CV swap.

[Zeeb]

my friends have been slammed for years and never needed that spacer, and they have never had any problems... i dont think thats the problem, one of my friend was slammed 5 inchs for over 3 years... and he's never had that kind of problem, theres probably something else messed up, im still thinking its the alignment..

[repiv]

my friends have been slammed for years and never needed that spacer, and they have never had any problems... i dont think thats the problem, one of my friend was slammed 5 inchs for over 3 years... and he's never had that kind of problem, theres probably something else messed up, im still thinking its the alignment..

Like I said, if he lowered it before a severe wear pattern developed, he won't have anything bad show up when he lowers it. Lots of people have lowered their cars and got no shakes. Why do you suppose doing the CV swap cures this shake? Honda even has a TSB on this with this exact symptom and it's directing attention to the CVs.
Alignment issues don't generally exhibit vibrational characteristics only on acceleration (which is typical of CV joint issues on a RWD car with 1/2 shafts and CVs). They tend to show directional irregularities on both acceleration, coasting and deceleration. Same goes for tire imbalances. They don't show up vibration only on acceleration.

Like I've also said, do the alignment because that's what should be done after lowering anyway. However, it's not likely this will solve the accelerative shakes. I hope it does and he can save a bunch of time and money.

[Ibn_danil]

I hope the shakes go away im not tryin to spend more money. Another question how much would a CV swap run me?

[repiv]

I hope the shakes go away im not tryin to spend more money. Another question how much would a CV swap run me?

Look at that link I put up where Jasonoff did this in his own garage. That'll give you some idea of the time involved. Find out what your shop charges per hour and you should have a pretty good guess of the cost.
Start with the alignment, then consider the spacers OR the CV swap. No point in doing both of the last two.

[Jasonoff]

my friends have been slammed for years and never needed that spacer, and they have never had any problems... i dont think thats the problem, one of my friend was slammed 5 inchs for over 3 years... and he's never had that kind of problem, theres probably something else messed up, im still thinking its the alignment..It's not the time period it's the distance they travel.

How many miles have they put on their car in those time periods?

I put about 80miles on my car before I lowered it aprox 2"

Also the more I think about this the more it appears this wear is in conjunction with axle nut torque. If the axle has the ability to slightly move in and out and constantly changing the direction the roller rolls in and out on the CV surface it may create the abnormal wear. Maybe a cross section scoring pattern of some sort.

Then when you lower the car you're not only changing how far in the roller makes contact but you're also slightly changing the direction it rolls back and forth by a degree or possibly less with a new cross section scoring pattern that chews the crap out of the surface. (Let me know if anyone needs more details on this.)

I think it is this new path plus the previous wear that creates the newly pitted area in a short amount of time or possibly right away. With this in mind if you lower your car before any signs of wear you may never run into this issue.

This may be why the half shaft spacers could possibly be the cats pajamas if you have a high mileage S2000 that you wish to lower.

[Ibn_danil]

So today i woke up at 8 and started working on my car i havent gotten the car alligned yet but i finnaly had to time to put the spacers in. Took me about one hour or so with a help of a friend and so far it seems like that the shakes are gone.

btw Thanks a lot repiv

[repiv]

So today i woke up at 8 and started working on my car i havent gotten the car alligned yet but i finnaly had to time to put the spacers in. Took me about one hour or so with a help of a friend and so far it seems like that the shakes are gone.

btw Thanks a lot repiv

Abso-freaking-lutely wonderful! Please keep up updated as you put more miles on it and with different kinds of accelerative forces. If my theory is correct, you've placed the CVs back into the configuration that resembles what it was before you lowered it and things should be back to normal till the CV joints get too badly worn, at which time, you won't be in any different situation than any of the rest of us when our cars get old.

[Jasonoff]

Humm maybe I'll toss in some spacers so i dont have any shaking on decel..