hapnermw

Before I throw a few stones at Phadt, I would like to thank them for putting the work into creating the spherical bearing kit for the Z06. While I've got some issues with their choice of bearing, the rest of the kit is very nicely designed and built.

I've had this kit installed in a mixed use street and HPDE Z06 for about two years. A year ago, a upper rear bearing got so worn it caused a high speed vibration and when replaced it also eliminated an annoying suspension rattle that had existed for some time. Now the suspension has developed significant 'popping'. The majority of this is coming from one upper rear A arm but I believe a number of other bearings also need to be replaced.

Before replacing more bearings, I decided to investigate exactly what quality of bearing Phadt used and what alternatives there were to replace the originals with something of higher quality/longer life.

Baker Precision is a supplier of spherical bearings to the racing, aircraft, etc market and provides some useful info on how to select spherical bearings for a specific application.

"Pro Racing: Aircraft Quality, Stainless Steel Body, Teflon Liner - Used in professional caliber racing cars of all types, from F-1 to NASCAR to CART. We recommend NHBB / NMB for these applications.

Race / Street: Chrome Moly Body, Teflon Liner - For lesser duty race applications such as Formula Ford, Sport 2000, etc, off road and street rods. For sprint cars, midgets and similar applications, we recommend the FK JMXT or JMT series (carbon steel body) where it is beneficial for the rod end to fracture instead of the suspension component.

Commercial: Carbon Steel Body - For throttle linkage, shift linkage and non - racing, lower stress applications."

The bearings in the Phadt kit are:
• FK COM10T ($12.95) - upper A arm
• FK WSSX10T ($17.95) - lower A arm

These are commercial spherical bearings. As Baker notes, they aren't normally used for racing applications.

I gave Phadt tech support a call and asked why they used commercial bearings in a racing product. I appreciate Phadt having tech support and I didn't expect them to be able to respond directly to this design/quality issue. I did ask them to pass on my issue with this choice and my suggestion that they either provide the option of using a better quality bearing or at least informing customers so they knew this was the case.

The pro racing alternative to these bearings are:
• NHBB ABT10 ($41.26) - upper A arm
• NHBB ABWT10 ($41.26) - lower A arm

I'll be replacing all the commercial FKs with NHBBs.

So for $62 per corner you get commercial quality and for $165 you get pro race quality.

I would have gladly payed an extra $400 on this $2K kit to avoid spending $1000+ in materials and labor to fix this issue after the fact. I suspect that most buying this kit would too.

sperkins

Where did you get those part numbers?

hapnermw

From the replacement bearing plastic bags Phadt previously sent me although it is pretty obvious based on dimensions and price of the bearing replacements what they are (and aren't).

hapnermw

The cost is primarily in designing and manufacturing the unique parts for the kit, not in the bearings themselves.

Using commercial bearings just devalues the product.

travisnd

I tend to work by the mantra "Do it right and do it once...". These are expensive parts to be used in racing, if a better bearing exists then it should have been used. Why use a cheap commercial grade component just to save a few bucks when your making a part for a race car and a racing version of the part already exists?

Pfadt Racing

hapnermw, thanks for your call yesterday. As you mentioned on the phone, you are using our spherical bearing kit on a street car with almost 100% street car use. Our product is manufactured for race use only, as we have always indicated online and in person. Street use requires different design criteria and if we targeted street use with this kit, we certainly had other options regarding street bearings, but more importantly the sizes would get bigger and add weight (not ideal for a race part). The wear rate of the bearings we supply in our kit is matched for the recommended application.

There should be absolutely no quality concern on the bearings that we use in our spherical kit. Ask any NASA Racer that uses our kit and you will get a straight answer that none of them have ever actually failed. Transferring noise or getting slight play in them is not failing and failure is not a current issue with the bearings in our kit. Our bearings, like all bearings, have a specific duty cycle to them, and will wear out from normal use over a given amount of time. Depending on how much and the type of use that is on them (and how many off track excursions you have), some will need to be replaced before others. Individual bearings may be replaced at a small cost to the owners. Street driving puts MUCH more wear and tear on products than typical race track use. Using our dedicated race products on the street will absolutely accelerate the rate of wear. This is inherent to EVERY bearing design, not simply the ones that Pfadt chooses. All bearings will be subjected to this wear rate regardless of price class.

Pfadt does not simply make products more expensive for the sake of it. If we were to use the most expensive materials and hardware in existence on every aspect of this kit, then it would increase the price of our kit 10 fold. There are plenty of more expensive bearing options than the one you highlighted above. But are they necessary for the kit? With all of our on-track testing we have supplied a product that is dedicated to racing performance and getting results. Just because something costs more does not mean it is better suited for a specific application. In this case, increasing the cost on the kit to cover an application in which we do not recommend using the kit for, is not the best way to supply customers with the best product. We strive to produce the best performing parts at prices that denote true value-added performance.

The bearings we supply in our kits are chosen on purpose for the application because they are high grade, have low friction values with zero maintenance, have the tolerances we require for manufacturing our parts to, meet the wear rate we specify for racing use, and have an excellent cost structure that does not gouge their customers. We do not get failures on these parts and quite honestly, we have sold 15 individual replacement lower bearings and 10 upper replacement bearings in the last 365 days, for the many thousands of individual spherical bearings we have in the field racing hard every weekend. With an ultra low replacement rate like that, we will continue to keep our product performing at a much lower cost to our customers

sperkins

I personally don't have any experience with Pfadt's spherical kit (other than rear lowers), but I do have a lot of experience with their staff and many of their other products. That being said, I don't believe posting negative comments about Pfadt Racing and their choice of bushing material is warranted when the problem you experienced may have been caused by you in the first place.

The team at Pfadt Race Engineering is staffed with smart people who do this for a living - it's not a joke to them. Their products are engineered using state of the art technology and tested in real word RACE conditions. They are one of a VERY small number of companies that support racers at the grassroots level with contingencies and technical support. Pfadt Race Engineering has many national and regional championships in their portfolio.
They have my full support.

J.R.

This is from my personal use only:
3 seasons of open road and road racing with these spherical bearings.
Some off course excursions.
None of the bearings have been replaced.
All are fully functional.
If anyone will be at the NASA Chuckwalla race in two weeks you may look at bearings starting 4th season. I am expecting some to need replacing some time soon. I just don't know when.

dfinke23

I think this thread is positive, for everyone involved. I was told by Pfadt two years ago when I ordered the SB kit that it wasn't intended for extended street use, and the bearings would wear prematurely if that was the case.
This upgrade may be an option for people with dual purpose cars that want the kit, or the upgraded bearings may cause other problems with the kit, but this is how we find out.

froggy47

Pfadt always steps up, when any of their components have a shortcoming. I've had 2 different issues on other components & was always more than satisified with their support.

"Perfect price, performance, installation" is a triple combo that rarely happens.

Tact

Per the rules regarding disputes, both parties have responded and this thread is now closed. Take it offline from here.

http://forums.corvetteforum.com/foru...-disputes.html