I didn't say it was a cheaper design. You have a problem don't you?

I said, "We were going to make our bushings like that too, it was a little cheaper, they would have had flat sides and been the same thickness down to the center steel bushing."

So let me explain that for you since you missed it the first time. IT WOULD HAVE BEEN CHEAPER FOR US TO HAVE OURS MADE WITH FLAT SIDES LIKE THE BUSHING PICTURED. I did not like the flat sided design and it cost US more to have our bushings built tapered like the factory bushing is.

David Buschur
www.buschurracing.com

 

There appears to be a significant difference between 80 and 90 durometer.
Some how these photos surely must translate into which would seem to be harder and less forgiving. To indicate that there's little difference between 80 and 90 durometer, well...

 

I found that "durometer" is a broad trem used by the industry. There are 4-5 different ways to check the hardness of the material. Depending on what the material is made out of requires a differnt "test." So if the BR and Powerflex monts are made out of 2 completely different materials the durometer hardness only reflects that type of material, so anyone can assume that these are the same hardness but just different characteristics of said material.

I guess if there is someone out there with a spectrometer then they can tell us what each mount is made out of then run a test with one type of durometer tester. I think that will tell us the truth.

I work in the plastics industry and will see if we have one of these testers at our shop, then I will buy both mounts and post up the results.

 

Not to knock Daves product, which I think is an excellent replacement, but i think the softness of the Powerflex could be attributed to the fact that is a two piece design. I think that the single solid piece would transmit more vibrations rather than a larger, two piece design that might not transmit as much.

 

Cheaper is relative to a monetary measurement in the context we were using it, just as you were. That is the definition we were using when we said "We don't see how it could be a cheaper design", (i.e. less expensive $ design). No, we don't have any problems, David.

Look forward to your results Mike! Glad someone has the more technical devices of measurement to further bring new info to the thread. We tried other ways to measure the hardness and flex properties such as bending each at the same angle on a digital scale and measure the weight it took to get there, but they kept slipping. Keep the thread informed of your findings.

If you had the two raw materials in your hand, it would make a big difference. Once you have had an 80 and 90D slip of urethane or the mounts themselves in your hand, you would be surprised that there is a substantial difference. There are some that have the mentality that 12.5% durometer could not be that much stiffer, but it is.

 

mmm how do you install the powerflex ones with hand tools?

 

I guess hack it... I had a hard time even with a press. I ended up using a dump truck size socket that barely fit on the metal band and then pressed it all through.

 

I think boostedwrx is describing how you get the old stock mount out, not the installation of the new unit.

Hand tools are not required. Powerflex units come with copper lubricant which Is used around the outer edge of the mount and you press it in by hand. Put both sides in and slide in the ss thick walled center sleeve and you are done.

 

Coming from the eclipse that rattled out your fillings it should be fine. We'll find out next week

If you want to see the difference in durometer first hand go to a sporting goods store and look at rollerblade wheels, there should be some in those ranges. It is a large difference in hardness.
Skateboard wheels will all be in the 98-101a range so they don't help.

 

I just ordered the buschur mounts. Ill let you guys know what i think of them when i install them.

 

Interesting squeeze test and the 300% more pressure. You have some very effective fingers there At first I thought that was a meter in your hand when I read the 300% but realized it is just more samples hanging.

Anyway, I was only passing along the conversation I got from the manfacturer. I looked into other mounts before we made our mounts and the high performance mounts I looked into advertised at durometer of 90, this is why I chose that number when we had ours done. I have to assume that when you take the material and make a large bushing out of it and then encase it into a steel sleeve (like the motor mount) that the little flex test from above has much less bearing on how "hard" the material seems. It would be like laying your head on a nice soft pillow and then jumping off the roof onto the same pillow, wouldn't seem quite as soft at that point.

David Buschur
www.buschurracing.com

 

I found that interesting too how they came up w/ that #. He must have some well calibrated hands!

 

If you like that, you will love that we estimate 95 durometer to 200% harder to bend than the 90D.

At these durometers 5-10 durometer increase is quite a difference in hardness quality. I would like to add that the material is at 76* at the time of testing. Imagine a 90 durometer mount in 40*F weather yikes! New definition for "solid motor mount"

 

What durometer scale are you each measuring your products at? Depending on the durometer test method the numerical value assigned to a specific hardness can varry quite a bit. You both need to figure out what scale you're each going on. (A, B, C, D, DO, M, O, OO, CF)

FYI 20D is harder than 90OO.

Once that's figured out, you'll be able to make a better comparison.

- Steve

 

I like the pillow analogy My only hesitation about the motor mounts is vibrating everything loose. On one of our DSMs we have very hard mounts and everything rattles loose after time. Everything from the interior plastic mounting bolts to the compressor cover bolts on the turbo. Locktite becomes your best friend.