Hey guys,

Wondering what your input was on these new pieces that Fly n Bye performance is featuring for 2011...

http://www.flynbye.com/catalog/i224.html

I think these are lighter than what we have (i have LS1 brake kit hubs)..

Are these strong enough for road racing / autox? And how much lighter are these compared to stock?

Thanks,
-Marc

I would be extremely nervous buying those without seeing more pictures and hearing who designed them and of what material. I'd also want to know the manufacturing process. Hubs are not something you want to fail.

Going solely on the price and simplicity of the hubs, my educated guess is that they are billet 7075 Aluminum. They could also be 6061, but that's not as strong as the steel that they are replacing.

I'd say your guess is pretty bold based on a single low res picture. It would be really nice if they were 7075 but I'd still be worried about toughness.

I ran aluminum G-body hubs on mine with no problems, These were from GLobal West and were dsigned to handle the strains of a 4000 lb roadrace g-body car.

Notice the rear sides are radiused.

These were overkill, I paid $500 for the pair custom made since they still had the CAD file for the one off they did for a project Wilwood was doing several years back-Yes, Wilwood subcontracted Global West for making hubs.

To be honest when I found the aluminum hubs on Fly n Bye's I thought of your g-body aluminum hubs you mentioned in one of your posts.. Didn't know they were custom made though and THAT expensive.. Geez.. lol.. But say if these were 7075 Aluminum hubs then would that be strong enough to handle road racing?

vetruck, do the g body hubs bolt right on to a thirdgens factory spindles, or do you have different ones?

I would definately use them without hesitation.

Same bearings. Bolts right to spindle.

Problem is they are a shallower offset. It did not matter to me though, I built a custom brake setup that was more inboard and then used long ARP wheelstuds and custom made hubcentric wheel spacers press fitted to the hubs.

Is there any issues with using longer wheelstuds and the IROC rims? I was planning on getting stronger studs just in case cuz the stock ones probably aren't strong enough for the high lateral stresses i'm planning on putting my car through..

There is nothing wrong with the stock wheel studs. If you break them its because the lug nuts weren't tightened or they are severely corroded.

I would be hesitant without knowing more about the material selection, heat treat, anti-corrosion coatings, manufacturing process, etc.

No. I also replaced the 12mm studs with larger 1/2" x 2.970" ARP studs no problems. The fronts I needed longer wheel studs due to the hub offset and having to make the .700" thick hub centric wheel spacer you will see pictured below. Then the final fitment shot of the entire assembly bolted onto the car for the first time- you could imagine the smile on my face when I dropped it on the ground and took the shot.

The rears I drilled and fit the Moser axles also with the same 1/2" ARP studs, But to keep the same reveal sticking out of the IROC wheels front and rear of the car, I machined the rear 2.970" length off by .325" so they were only 2.645" length since the rear did not have front hubcentric .700 spacer. I ran a 3/8" wheelspacer on the rear to slightly change the rear track to match the front off set of .318" more to match the 1LE factory offset. I also changed my IA (Inclination Angle) to reduce the positve scrub radius.

Also, I run thr same ARP wheelstuds on my truck and just recently snapped a rear stud- Looking at ARP's website it appears form their own decription of wheel stud failure pictures that they had a flaw in my casting when it was manufactured. The stress marks and pit match a manufacturing defect.

While these are important, none of them really matter. The important thing to keep in mind is that 7075, while stronger than steel, suffers from Stress-Corrosion Cracking. It won't show a single sign of wear until the whole thing just cracks in two. Theres a great display of it in our Aero Engineering building from aircraft landing gear. I'll try to get a pic of it this week.

Keep in mind, aluminum dings easily which means that coating will only work until it gets chipped. As for my opinion being bold, its really not. I've made hubs before and 6061 would work, but it'd also be super bulky. 7075 has better strength than steel and allows for less bulk, but the trade off is SCC.

You actually hit my point exactly. 7075 has poor corrosion characteristics and the coatings are critical for long term performance. I happen to work in the aerospace industry and we try to limit the use of 7075 for this reason.

Also there is no reason for a hub to ever get dinged in normal use. I don't see this as an issue.

The heat treat on 7075 is critical. It can change the properties significantly.

I'm just trying to help. The last thing you want is for a hub to crack in half on the track.

I can recall an example in the C4 world where there were a bunch of failures of aluminum hubs on the track. It ended up being attributed to the manufacturing process where the manufacturer was casting the parts instead of forging. Big mistake and cost a few people their cars.

I think it would be in your best interest to call Ed and get some details.

Purdue?

Yep. Its the trunnion support for the hydraulics IIRC.

As for a coating, I think that Class III Hard Anodizing would work, but for how long I don't know. Alot of people don't realize that 7075 in and of itself isn't a specialty alloy, its the heat treatment that makes it 7075 and strong as steel.

I found this book on google books..

http://books.google.ca/books?id=ck4a...page&q&f=false

Not sure if that link is going to work but check it out. They mention the stock studs not being strong enough for racing.. Studs are cheap no? I figure why not spend the extra 60-70$ for stronger studs.

Vetruck: So by installing the hubs you increased your track width, right? And wow.. ARP stud failure is surprising since they are supposed to strong enough to handle that type of driving, kinda scary..
I have stock 26 spline axles, would it be worthwhile to go with new 26 spline forged moser axles with arp studs? Also I've heard c-clip eliminators are safer as well..

9bolt

Tech Article on the 10-bolt from TGO :

https://www.thirdgen.org/beefinguprear

check out #17 & #18 posts in this thread:
https://www.thirdgen.org/forums/brak...e-fitment.html

The hubs look fine to me. The supplied stud bolts were way too short.

Yes I read this many times but it doesn't really apply to lateral forces, more for drag racing. I just want to be sure because I do not want anything to break or snap off while i'm turning through a corner at high speed.

TEDSgrad: So these hubs would need new studs anyway? Good to know.. Did you manage to get the new ARP ones installed?

TEDSgrad: So these hubs would need new studs anyway? Good to know.. Did you manage to get the new ARP ones installed?[/quote]

I'll let you know this weekend. We melted to the grass last week, then had 10" of snow last Tues night!
I'm planning on putting the bolts in a drill press to rotate them, then lightly file the knurls a little. Then I'll put the lug nuts on and draw them in. That should work just fine. The supplied studs are an odd knurl size - looked all over. Found a doorman part but all those were too short. Plus, I just like ARP.

Here's a pic of the difference between studs.

I cannot view the page but interesting non the less. I have not heard of a single failure on any car. Either way as you say new studs are cheap.

I assume you got the hubs from Ed? If so did he provide any info on their origins? or any other details?

Agreed they look good. However with something as critical as hubs I'd like to see something a little more than the eyeball test.

Let me try to paste this again lol..

http://books.google.ca/books?id=ck4a...page&q&f=false

You have to scroll up one page to see the part about the studs.

Yes, got them from Ed. They look stout and are heavier than I expected, though still much lighter than stock. I'll take a look this weekend, but I don't recall any markings - remember thinking that they were darker colored than I expected for aluminum.

They are probably/hopefully anodized.

I just messaged him about the hubs, i'll keep you guys informed.

I just put the the stud bolts in. Just drew them in by tightening the lug nuts. The last 1/8 in needed some strength, but no filing on the bolts!
I did not see any markings on the hubs, but I did not look close. I just wanted to know that the bolts are the right ones.

http://www.summitracing.com/parts/ARP-100-7706/

Do you guys know if these arp studs will fit stock 16 inch iroc wheels?

One other thing that hasn't been mentioned yet in this thread is heat. No matter how good the heat treating is on an aluminum part originally if your running a road race pad like a carbotech xp-12 and getting the pads well over 1000 degrees, a good amount of that heat is going to make it to hub and ruin your nice hubs in short order.

I doubt you have anything to worry about if you don't have or need true race pads like most autox'ers or street/drag cars. I would definitely give them a good look over every couple times I had the wheels off...

7706 will fit the stock rims, but what hubs are you talking about?
The 7706 knurl is too narrow for the aluminum hubs (length & thread is fine) - the studs spin in the hub making tightening and loosening the nuts a real chore. PLUS - you do not want narrow studs in the hub holes at 150 m/hr no matter how tight they are on the wheel! The 7706 should work fine on stock hubs, though you may have to run a drill press through each hub hole so the knurl fits (minimal amount).
I drew in the 7715 till the knurls seated fully, then backed off and re-tightened them.
While I was doing that, my water pump went, and spilled anti-freeze all over the driveway. Better in my driveway than at Road America!

anybody ever hear from ed on this?

No I did not. I emailed but did not receive a reply. But they are moving their operations so they are not taking orders for kits right now anyway, so I'm sure they don't have time to reply to emails.

I have a feeling Ed is probably using the hubs from another vendor, guessing about the "darker appearance" I think I know who he probably buys them from but I wont speculate in the public forum but I have them and they have been very good to me. I also got the extended ARP wheel studs when I bought them. I was a little miffed when I found out that the place now (I think) type III anodizes them now and I wish mine had been. But overall they are nice pieces and should not have any problems in racing or auto-x. I got my 12" Wilwood kit from Ed and I sent him my hubs for him to make my set so I think he is probably re-selling what I had bought, but I could be wrong

Info from where I bought mine from:

CNC machined
6061-T6511 billet aluminum
Dual 5 x 4-3/4" wheel patterns
3.10 lb [1.40 kg] each
Anodized black

Regardless of what Ed uses. Care to share what you used?

I assume the weight is the main advantage of going to aluminum hubs. If so does anyone know the weight difference? I see in the post above the aluminum ones weigh 3.10 lbs.

For everyone talking about Anodizing, you need to do your research.

Aluminum has one major flaw that affects it much more then steel. Fatigue. An aluminum part will break. It is a matter of when not if.

Anodizing DECREASES the fatigue life of aluminum components. In other words, it causes it to fail quicker.

Remember this the next time you want something anodized just because it looks pretty.

Would love to know the weight difference as well.. This is unsprung rotating weight so it counts for more than sprung weight that isn't rotating, or even unsprung weight that isn't rotating.

I'll try giving Ed a call today to ask about this piece. I just can't seem to get through to him.

Edit: Had spindles on the mind not hubs.

I weighted mine today, they are stock hub/rotor, with the rotor cut off.
they are 9lbs, with studs bearings and grease, as you can see in the pic.

My understanding of Anodizing is different to yours
Aluminum has an oxide layer anyway this is one of the reasons why its more difficult to weld. the oxide layer is more dense and takes more heat to liquidify where as the main section of aluminum takes far less heat, that where the skill of the welder is critical, noticing how the material is changing state.
Anodizing basically thickens this layer (which can be dyed to give that "nice finish")
Without refreshing myself on it, and off the top of my head it would be wrong to say that it doesnt decrease the fatigue life. But I do know that when im specing a part to be anodized Im doing it to increase the part surface hardness and increase its corrosion resistance.
not saying that just becuase u anodize aluminuim it doesnt corrode anymore... cos it does just not as fast.
All materials its a matter of when not if
like for like yer steel is stonger, but high end aluminums can match and outperform a range of steels, obviously is never going to out do high end high strength steel, but if the forces on the part dont exceed the properities of the aluminuim then the part is okay to be built from aluminuim.


Be interested to know what grade of aluminuim these hubs are, and what the grade of steel the stocks were made from.
id be interested as long as u know the aluminuim is up to the job.

just my 2 cents

Okay, I need a little help with this. If I were to buy the aluminum hubs in post #1 which rotors do I need? I am running stock brakes up front with Wilwood aluminum calipers. How does the rotor attach to the hubs for example? It also appears that there is about a 6 pound savings per side for a total of 12 pounds.

the hubs are for people doing brake upgrades (LS1, C4, etc) not stock brakes. they are slip fit like most modern sealed hub/bearing unit; hub stays installed on spindle and rotor slips over hub for installation

Thanks Dan. That explains it.

12 pounds of rotational weight is significant! If it's the same strength or stronger than stock i'm going to get these.

There have been several studies showing that anodizing does decrease the fatigue life. You can do a search on that if you would like. I dont have a link right now off the top of my head but Im sure you could find something form google.

Here is one http://www.experimentalhelo.com/Anodizing&Fatigue.pdf

and another. http://www.finishing.com/444/19.shtml

Anodizing has its uses. It just depends on what you are doing with the part. For a high fatigue part like a hub, I would recommend not using it especially if a non-anodized part was offered. (which I dont even know if it is or not) These hubs with an anodized finish may last 1 million miles, I dont know. All I know is that the nonanodized will outlast the anodized.

On the other hand, anodizing is very effective at reducing corrosion. Depending on the type of AL, corrosion will reduce the fatigue life much faster than the anodize. The aluminum needs to be coated in some way to prevent corrosion.