Hi H-T dudes,

I'm starting to realize that autocrossing and track days indeed cause a person to pay more attention to upkeeping a car...

Chasing front end vibrations is becoming a continuing saga. So what's happening is the vibration seems to increase steadily with speed. I've done a few things to combat this, but it seems the vibrations continue to surface. I'm now at the point were I'm either going to just drop the car off somewhere and say keep it until it's fixed, rebuild the entire front suspension or sell it.

Earlier this year, stock struts were replaced with Koni singles. This helped the occasional/intermittent (sp?), and somewhat violent vibration. Problem solved? Well for a little while anyway.

At the moment I've had the wheels balanced twice, and each time they are fine until I autocross, ie, jack up, switch to R-compounds, jack up and switch back. I'm figuring that either the people aren't balancing the wheels correctly, or only balancing the fronts, since I don't necessarily put the street tires back on the way the came off (front and rear that is). I never had a problem with this until recently.

So, I'll probably try having the wheels balanced, again (roll eyes). Then I'm kind of at a loss.

There was a small amount of play in the steering rack... inner tie rod was replaced. Right side wheel assembly is all new... spindle, bearing, wheel studs, etc.

Rotors are fine... in fact it seems to reduce the vibration when brakes are applied.

Half shafts are about 3 years old.

Wheel baring on left side is also about 3 years old... cause of suspect

In talking to someone recently, they suggested replacing the motormount bushings.

Other suspension bushings are original... also cause of suspect.

Before I go replacing the whole front suspension, sigh, any suggestions, or similar stories?

Thanks in advance for any help!

 

Well i just replaced an inner CV... i had an odd vibration under acceleration since i bought the car, but it was never severe enough to actually do anything about until 2 weeks ago. Now the vibration is totally gone.

 

Are your wheels lug centric or hub centric? At what speeds do you first notice the vibration? How much worse does it get at freeway speeds? Does it happen only under power, or if you put the clutch in, does it still vibrate?
My first instinct is to think that you are putting your wheels back on crooked. This is easy to do with lug centric wheels. Next would be to take a look at the axles/cv's. Hope that helps.

 

Thanks for the responses:

The vibration increases with speed, and still happens when the clutch is pushed in.... not just under acceleration, but at cruising speed.

Wheels are hub centric, CRX Si, but aided with tapered lugs, if that makes any sense.

I could be putting the wheels on crooked, hard one to admit, but I suppose that certainly is possible... and very easy to solve.

CVs, again hard one to admit, since they are only 3-4 years old. More so, because they're so derned expensive to replace.

 

3-4 years old seem pretty old for CVs in a autoX/track car. What year crx is it? I have an 87 with the torsion bar front suspension. To chase a vibration I usually check bearing, steering linkage, balljoints, strut/hub bolts, bushings, then CV joints in that order. If everything else is Kosher it's gotta be that CV.

And I would recommend you replace them anyway. My brother was chasing a vibreation for weeks that just kept getting worse. the vibration eventually sheered off the wheel studs, wrecking the front suspension. so he got a whole new assembly, so he really replaced EVERTHING and went out the next day. In Practice the vibration came back, but only for a second as the CV joint blew. No problems since he replaced it. The CV was 6 months old.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gotocrx &raquo;</TD></TR><TR><TD CLASS="quote">3-4 years old seem pretty old for CVs in a autoX/track car. What year crx is it? I have an 87 with the torsion bar front suspension. To chase a vibration I usually check bearing, steering linkage, balljoints, strut/hub bolts, bushings, then CV joints in that order. If everything else is Kosher it's gotta be that CV.

And I would recommend you replace them anyway...</TD></TR></TABLE>

Thank you! (seriously) You have helped make it obvious to me that maintenance on an autocross/trackday/everyday driver is not the same as what it would be on an everyday driver alone.

dave, who's mechanic skills are in the "novice" stage and bracing for another large bill.